Notas / Notes - Active Congress.......

VI Curso Internacional de Artroplastias 

VI International course in Arthroplasties 

2008 

LIBRO DE RESÚMENES / ABSTRACT BOOK 


VI Curso Internacional 

de Artroplastias 

VI International course 

in Arthroplasties 

Barcelona, del 8 al 11 de Abril de 2008 

Barcelona, 8 to 11 April 2008 

Dirigido por / Directed by: Antonio Navarro Quilis 

Co-directores / Co-directed by: Enric Cáceres Palou 

Joan Nardi Vilardaga 

Sede / Venue: Auditori Winterthur-Illa Diagonal 

Universitat 

Autònoma 

de Barcelona 

www.artroplastias.com



Edita: ACTIVE CONGRESS 

Rda. Gral. Mitre 17, Entlo. 4ª 

08017 Barcelona 

Tel. +34 93 205 09 71 

Fax +34 93 205 38 52 

info@activecongress.es 

www.artroplastias.com 

Diseño gráfico: r&p asociados 

Imprime: Cevagraf, SCCL 

Depósito legal: B-17799-2008 

Marzo 2008






Dirigido por / Directed by: Antonio Navarro Quilis 

Co-directores / Co-directed by: Enric Cáceres Palou 

Joan Nardi Vilardaga

La organización agradece la colaboración de:

El Curso Internacional de Artroplastias comenzó en el año 1999, y 

en esta, su sexta edición queremos, como siempre, agradecer a 

todos los ponentes, en nombre de los Directores y en el de todos 

los asistentes al Curso, el esfuerzo que ha supuesto el enviar los 

resúmenes para su publicación. 

Un libro de resúmenes constituye el mejor recuerdo y, al mismo 

tiempo, el mejor elemento de trabajo para el aprovechamiento de 

las enseñanzas de tan valiosos expertos. 

Aprovechamos la ocasión para agradecer el apoyo recibido por la 

industria y dejar bien patente que a no ser por su generosidad, ni 

este curso ni muchas de sus otras actividades de la educación 

médica postgraduada, podrían realizarse. 

Antonio Navarro Quilis, Enric Cáceres Palou y Joan Nardi 

Vilardaga 

Directores del Curso 

The International Course in Arthroplasties is running since 1999, and 

is in its 6 th Edition; on behalf of the course audience we would like 

to thank the Faculty for the effort made sending the abstracts for 

publication. 

The book of abstracts is the final tool for getting the most out of the 

course content; as well as being a souvenir of the experience. 

We would also like to thank industry for its help, and point out that 

without its generosity, this course and many other CME activities 

could not be carried out. 

Antonio Navarro Quilis, Enric Cáceres Palou and Joan Nardi 

Vilardaga 

Directors of the Course 

INTRODUCCION / INTRODUCTION

Índice de ponentes / Speakers index 07 

Programa diario / Program 

CADERA / HIP 

Martes, 8 de abril / Tuesday, 8th April 13 

Pares de fricción y nuevos materiales / 

Friction couple and new materials 14 

Fijación de los componentes protésicos / 

Fixation of the prosthetic components 24 

Doble cúpula y vástago corto / 

Resurfacing and short stem 36 

CADERA / HIP 

Miércoles, 9 de abril / Wednesday, 9th April 49 

Abordajes quirúrgicos: MIS y Navegación / 

Surgical approach: MIS and Navigation 50 

Cadera difícil y complicaciones de las artroplastias / 

Difficult hip and complications 62 

Cadera de revisión / Hip revision 84 

CADERA / HIP 

Jueves, 10 de abril / Thursday, 10th April 105 

Acetábulo de revisión / Revision Acetabulum 106 

Infecciones / Infections 120 

RODILLA / KNEE 

Jueves, 10 de abril / Thursday, 10th April 122 

Unicompartimentales / Unicompartimentals 122 

PTR, MIS y Navegación / TKA, MIS and Navigation 136 

Rótula / Patella 140 


Viernes, 11 de abril / Friday, 11th April 147 

Prótesis total de rodilla / Total knee arthroplasty 148 

Complicaciones / Complications 198 

Rodilla de revisión / Revision knee 206 

INDICE GENERAL / GENERAL INDEX

Índice Ponentes 

Speakers Index 





INDICE DE PONENTES / SPEAKERS INDEX

INDICE DE PONENTES / SPEAKERS INDEX 

Índice Ponentes 

Speakers Index 

Harlan Amstutz 

- Current status of hip resurfacing-what have we learned 38 

- Hip resurfacing for osteonecrosis 42 

- Indications and results of childhood disorders (DDH,SCFE,LCP) with the Conserve® 44 

Plus Hip resurfacing 

Keith R. Berend 

- Unicompartmental knee arthroplasty with mobile bearing 128 

- Constraint in revision total knee arthroplasty 216 

- Dealing with severe femoral bone loss in revision total knee arthroplasty 218 

J. David Blaha 

- Osseointegration in primary cementless hip fixation 24 

- Advantages of the use of modular necks 76 

- Medial pivot knee arthroplasty 188 

- Femoral component positioning in TKA. A 3-D problem 192 

Agustín Blanco Pozo 

- Tantalio en cirugía de revisión 108 

Peter Bonutti 

- Selecting the best approach for MIS TKA 136 

- Pitfalls & complications of MIS TKA 138 

- Mobile Bearings: are they worth it? 196 

Albert Burstein 

- Unicompartmental knee replacement: mechanical considerations 128 

- Geometry, ROM and wear: relationship 194 

Lluís Carrera Calderer 

- Vástago encerrojado IRH 92 

David Dalury 

- Unicondylar knee replacement 128 

- Mini-incision TKA 138 

- Diagnosis and management of mid- flexion instability following TKR 204 

- How to decrease wear in TKR 206 

Hendrik P. Delport 

- How small changes in cement technique can have a big influence in hip resurfacing 40 

- MIS Knee. A soft tissue operation 136 

- Post-Cam behaviour in PS-TKA 194 

Douglas A. Dennis 

- Leg length inequality: prevention and management 80 

- Advantages of patellar resurfacing 140 

- Factors affecting flexion after. Total knee arthroplasty 180 

- Measured resection versus gap balancing technique 184

Lawrence Dorr 

- MIS THR: why, how and results 50 

- THR: computer navigator, combined anteversion and large heads 56 

- Rapid recovery THR: pain, anesthesia, pain management, and same day discharge 78 

Mariano Fernández-Fairen 

- Tantalio, propiedades y ventajas 20 

Alois Franz 

- Bi-compartmental knee 130 

Michael A. R. Freeman 

- The movement of the normal tibio-femoral joint 148 

Jorge O. Galante 

- Cementless cup: lessons from retrieval studies 34 

- Cementless cups in revision surgery: clinical experience in the long term 118 

- Long term clinical experience with cruciate retaining TKA 192 

Reinhold Ganz 

- Consideration on surgery and prosthetic design in resurfacing arthroplasty of the hip 44 

- Management of the painful hip of the young adult 62 

- Revision surgery for mega - deficiencies including nonunions of the acetabulum 118 

Eduardo García-Cimbrelos 

- Cambios óseos tras la utilización de vástagos largos en cirugía de revisión 90 

Rudolph Geesink 

- Cemented or cementless fixation of hip implants? 24 

- Basic science of HA-coatings 26 

- Prevention and treatment of recurrent dislocation in hip arthroplasty 74 

- Diagnosis of the painful cementless hip 80 

- Long term results in HA-coated revision hip arthroplasty 100 

Thorsten Gehrke 

- Midterm results of a femoral preserving stem 46 

- Different methods to reconstruct acetabulum in cases of severe bone loss 118 

- The marsa ghost 120 

Javier Gil 

- Study of wear behavior in a hip joint simulator of different CoCrMo counterfaces 14 

on UHMWPE. 

Victor M. Goldberg 

- Clinical and histologic results related to a low-modulus composite total hip 28 

replacement stem 

- The incidence of thigh pain and clinical outcome of a tapered femoral stem 80 

- The success of isolated patellar component revisions following failed 140 

metal-backed patellar TKA 

- Wear analysis of retrieved UHMWPE tibial components from rotating platform 196 

total knee replacements 

Damian Griffin 

- Hip arthroscopy for femoro-acetabular impingement 62 

- MIS inTKA 138 

Richard “Dickey” Jones 

- Arthroscopic lateral patella facetectomy for severe patella femoral arthrosis 140 

- Soft tissue in TKA, approaches and releases 180 

- High flexion, rotating platform total knee arthroplasty: scientific basis and 196 

clinical experience 


INDICE DE PONENTES / SPEAKERS INDEX 

Ricardo López Martínez 

- Prótesis modular con hidroxiapatita 28 

Francisco Maculé 

- Navigation in TKA. Principles 136 

Peter McLardy-Smith 

- Surgical techniques in revision hip arthroplasty 84 

- The diagnosis and management of peri-prosthetic infections 120 

Michael Menge 

- Avascular necrosis and hip resurfacing 42 

- Resurfacing in the Elderly patient 42 

- MIS versus standard posterior approach in hip resurfacing 56 

- Hip resurfacing arthroplasty in dysplastic hips 72 

Carles Mestre 

- Fracturas periprotésicas de fémur 100 

Thomas J. Moore 

- Bone growth enhacing factors 222 

Antonio Murcia 

- Prótesis total de cadera y enfermedad displásica de cadera 64 

- Anillos de sostén, de refuerzo y antiprotrusión en reconstrucción acetabular 112 

Antonio Navarro 

- Prótesis modular con hidroxiapatita 28 

- Vástago encerrojado IRH 92 

José Palacios 

- Cúpula de doble movilidad 76 

James B. Richardson 

- Metal-metal couple – scientific bases 18 

José Rodríguez 

- The management of periprosthetic femoral fractures utilizing 88 

a cementless total hip revision system with modular distal fixation 

- Two- to five-year follow-up of mostly type III femoral defects in revision 100 

THR treated with the link MP stem 

Carlos Rodríguez-Merchan 

- Management of periprosthetic fractures in total knee arthroplasty 222 

José Romero 

- The impact of ligament balancing in total knee arthroplasty 180 

- Treatment of Stiffness after total knee arthroplasty 200 

Cecil Rorabeck 

- Metal/Metal bearing surfaces: the way of the future? 18 

- Resurfacing total hip arthroplasty: an emerging technology 36 

Aaron Rosenberg 

- Acetabular fixation-several options 30 

- Impacted bone graft in femoral revision 84 

- Acetabular revision: bone loss is not the only issue 106 

- Unicompartmental knee arthritis. Unicompartmental VS total knee arthroplasty 132 

- Tantalum and revision TKA 218

Laurent Sedel 

- Ceramic – ceramic couple a 38 years experience 20 

- Total hip replacement with all alumina bearings in patients under 30 years of age 64 

- Revision strategy at the femoral level 88 

S. David Stulberg 

- The rationale, surgical technique and results of using short, metaphyseal stems in 46 

THA. Short stems, the next generation of implants in THA 

- The role of computer assisted surgery in training surgeons to perform TKA 136 

- Grafts and augments in revision knee arthroplasty 218 

Thomas Thornhill 

- Unicompartmentals: osteotomy, interpositional device or unicompartmental? 122 

- Evaluation of the painful total knee 198 

A. John Timperley 

- Role of the cement in the fixation of the prosthetic components 24 

- Cemented cups: results and technique 32 

- Resurfacing versus traditional arthroplasty 46 

- Cement-in-cement revision -decreasing the morbidity of revision surgery 84 

- Impaction graft technique in the socket 108 

Ronan Treacy 

- Ten year results of the birmingham hip resurfacing 38 

Jan Victor 

- The Kinematics 172 

- The extensor mechanism in revision TKA 208 

Leo A. Whiteside 

- TKA without patellar component 144 

- Ligament balancing in the varus knee 186 

- Ligament balancing in the valgus knee 190 

B. Michael Wroblewski 

- Charnley LFA in the teenager. Follow-up to 34 years 62 

- Charnley low-frictional torque arthroplasty. Follow-up to 38 years. Problems and Solutions 72 

- Infected total hip arthroplasty. One stage revision 120 

Karl Zweymüller 

- Threaded cups, when? 32 

- Results with cementless stem revision 88 


Martes, 8 de abril 

Tuesday, 8th April 

CADERA / HIP 

Pares de fricción y nuevos materiales 

Fijación de los componentes protésicos 

Doble cúpula y vástago corto 

Friction couple and new materials 

Fixation of the prosthetic components 

Resurfacing and short stem 

Moderadores / Moderators: Victor M. Goldberg, Cecil Rorabeck, Luis Azorín,

MARTES / TUESDAY 

14 

09.00 - 10.45 h 

CADERA / HIP 

Pares de fricción y nuevos materiales / Friction couple and new materials 

Moderador: Victor M. Goldberg 

STUDY OF WEAR BEHAVIOR IN A HIP 

JOINT SIMULATOR OF DIFFERENT 

CoCrMo COUNTERFACES ON UHMWPE 

F. Javier Gil 

CREB. Dept. Ciencia de Materiales e Ingeniería Metalúrgica. 

ETSEIB. Universidad Politécnica de Cataluña. 

Barcelona (Spain) 

The objective in these wear tests was to study the effect of 

different material counterfaces on the UHMWPE wear behaviour. 

The materials used as counterfaces were based on 

CoCrMo: forged with hand polished and mass finished, 

CoCrMo coating applied on the forged CoCrMo alloy obtained 

by Physical Vapour Deposition (PVD). A Hip Joint Simulator 

have been designed and built for these studies. The worn 

surfaces were observed by optical and scanning electron 

microscopy. The results show that the hand polished CoCrMo 

alloy caused the higher UHMWPE wear of the acetabular 

cups. The CoCrMo coating causes the least UHMWPE wear, 

while the mass finished CoCrMo alloy causes an intermediate 

UHMWPE wear. 

MATERIAL AND METHODS 

The tests on the HJS wear test method were performed as 

follows (Figure 1). The acetabular cups were mounted on a 

home-made metal back support to transmit the load to each 

of the three stations. The cups were then pressed against 

the femoral heads. While the cups remains static, the heads 

slides according to the biaxial rocking motion. A constant 

load of 1000 N (102 Kg) per station was applied during the 

test. The frequency of the motion was 1.23 Hz (810 ms/cycle). 

In the HJS a cycle is considered as completion of one rotation 

of the head. The wear of the UHMWPE cups was determined 

by weight loss measurements every 333,333 cycles up to a 

total test length of 3 million cycles. The test lubricant was 

replaced with fresh solution after every weighing stop and 

distilled water was added during the test for compensating 

water evaporation. Each station has an environmental test 

chamber made of a transparent polycarbonate wall. Each 

chamber has been filled with 350 ml of lubricant. As test 

lubricant, a solution consisting of bovine serum and distilled 

water was used with a total protein concentration of 30 mg/ml. 

The serum was purchased at Sigma-Aldrich SrI (Calf serum, 

bovine donor; product No.C9676). The soak adsorption of 

the UHMWPE cups was determined using an additional 

control cup, which was loaded identically as the UHMWPE 

cups in the RPOF machine, but no motion was applied. The 

cleaning and drying of the UHMWPE cups was performed 

according to the ASTM 1715 standard. Weighing was carried 

out with a Mettler Toledo AT261DeltaRange® microbalance 

with an accuracy of 10±µg. 

Acetabular cups made of UHMWPE GUR1020 and previously 

sterilised with 25 KGy (2.5 Mrad) gamma radiation were 

used. The cups were supplied by the SAMO S.p.A. and 

received with their packaging, as they are commercialised. 

The cups are designed to be used with a metal back component 

and in conjunction with 28 mm femoral heads. The 

articulating counterfaces were therefore 28 mm femoral 

heads. Three different femoral head materials were studied, 

the standard material in this study was a hot-forged CoCrMo 

alloy. Table shows the chemical composition of this material 

and Table 2 the hardness and roughness of each material. 

· CoCrMo forged (hand polished) 

· CoCrMo forged (mass finished) 

· CoCrMo forged with a CoCrMo coating obtained by means 

of physical vapour deposition (PVD). The coating had the 

same chemical composition as the substrate. 

For each articulating counterface material three heads were 

tested. A total of 18 wear tests were performed. The test 

conditions and materials for the HJS wear tests are resumed 

in Table 3. 

RESULTS AND DISCUSSION 

The wear of the UHMWPE specimens (cups) in the HJS 

wear test method are shown in Figure 2, where the volumetric 

wear (mm3) of the UHMWPE cups is represented as a 

function of test duration in cycles for each the head material. 

The volumetric wear results are calculated from the average 

weight loss of three specimens. 

The results shown above after 3 million cycles present a 

high linearity and a low standard deviation. The standard 

deviation after 3 million cycles, represents for the hand 

polished alloy and the CoCrMo coating 10.20% and 4.66% 

respectively, and 6.95% for the mass finished alloy.

Notas / Notes 


15


16 

The results presented show that the hand polished CoCrMo 

alloy caused the higher UHMWPE wear of the acetabular 

cups, when tested with the HJS. The CoCrMo coating causes 

the least UHMWPE wear, while the mass finished CoCrMo 

alloy causes an intermediate UHMWPE wear. 

The wear zones were observed at high magnifications with 

a SEM to observe the very fine microstructure remaining 

after the wear tests. The SEM observation was focused in 

Table 1. Chemical composition of the forged CoCrMo alloy (%) 

the formation of UHMWPE particles that detach from the 

worn surface producing wear debris. The border zones in 

all cups have a similar ripple-like microstructure; there is 

almost no UHMWPE particle formation in this wear zone. 

For all the cups observed, the microstructure of the polar 

zones appears likely to be ripple-like but less accentuate 

than in the border zone. On the other hand, the UHMWPE 

particle formation could not be seen. 

Element Cr Mo Mn Ni Si Fe C N 

Balance 26-30 5-7 max 1 max 1 max 1 max 0.7 max 0.35 max 0.25 

Table 2. Roughness and hardness of each material tested 

Material Roughness Ra Hardness 

(µm) (HVN) 

Hand-polished 0.03±0.01 673±21 

Mass-finished 0.05±0.01 840±62 

CoCrMo coating 0.10±0.01 884±28 

Table 3. Test conditions of the HJS wear tests 

Test parameter Value 

Type of motion Multidirectional (BRM) 

Contact geometry Real (as in a hip joint replacement) 

Frequency 1.23 Hz (810 ms/cycle) 

Contact area Real, as in hip prostheses 

Load applied 1000 N (102 Kg) 

Test length 3 million cycles (at intervals of 

333,333) 

Lubricant 30 mg/ml initial protein content 

Temperature Room 

Acetabular UHMWPE GUR1020 

component (cup) 

Femoral CoCrMo forged (hand polished) 

component (head) CoCrMo forged (mass finished) 

CoCrMo forged with a CoCrMo coating 

Table 4. HJS wear tests: UHMWPE cups wear rates. 

Wear rate R 2 

(mm 3 /106 cycles) 

Hand polished 90 0.998 

Mass finished 68 0.993 

CoCrMo coating 44 0.998 

Figure 1. Motion/loading configuration of the HJS wear test machine. 

Figure 2. Average wear losses of the UHMWPE cups in the HJS wear 

tests.



17


18 

METAL-METAL COUPLE – SCIENTIFIC 

BASES 

Eric Robinson, Tajeshwar Singh Aulakh, Munir Khan, 

Jan-Herman Kuiper, James Richardson 

The Robert Jones & Agnes Hunt Orthopeadic Hospital. 

Oswestry Outcome Centre, Oswestry (Great Britain) 

Science is based on observation. Any hypothesis should 

then fit those observations and be open to testing. Metal on 

metal hip replacement was very successful with a design by 

Ring some 30 years ago. There were difficulties however 

with initial fixation to bone. I will show a case where a loose 

Ring stem was simply revised by re-cementing the original 

stem, and 8 years later the patient is functioning well! This 

observation helped to question the teaching I had received 

against metal-metal bearings. 

The metal on polythene hip has stood the test of time but 

John Charnley himself insisted it only be used for the older 

patient of 65 years or more. Some excellent long term results 

have been obtained in patients who had some other limiting 

factor from a young age that prevented them attaining a high 

mileage each year. We all know the problems of osteolysis 

related to the polythene debris from a metal on polythene 

joint. It is for these reasons that there is again a logical argument 

for using a metal on metal articulation in the younger 

and active patient. 

The Outcome Centre at Oswestry has been following 5000 

hip resurfacing (BHR) now out to 10 years. This is an independent 

review where information is gathered directly from patients. 

This has found a very high level of function and activity 

in patients with metal on metal resurfacing hip replacement. 

There is good survival out to 10 years with 95% survival. This 

group of patients is from a combined series of several surgeons 

across the world who were new to using this technique. 

Similarly, I have excellent results now out to 10 years with 

the Metasul articulation on a Thrust Plate. This is a short uncemented 

stem with strong initial stability and rigidity. These 

patients likewise have a high level of activity and the 8 year 

follow up was a 98% survival. 

What of the metal ions absorbed? Certainly in a minority of 

patients these have a hypersensitivity response which causes 

pain and cyst formation. All patients absorb some metal in 

the form of chromium and cobalt. These levels are highest in 

the joint and adjacent to the metal implants. Alterations in 

circulating cells have been noted and this causes concern. 

However, the observation of a local sarcoma adjacent to a 

metal implant is very rare indeed considering the numbers 

implanted worldwide and this includes a whole range of metal 

implants. The observation therefore is that in practice and 

indeed over many years it is unlikely that the risk of a local 

cancer is significant. Further observations and studies are 

needed to identify and quantify risks of leukaemia. 

The ‘bottom line’ is whether patients with hip resurfacing are 

dying at a faster rate than expected. Tajeshwar Aulakh has 

studied the mortality rates of the Oswestry 5,000 and finds 

the rate almost half as low as the expected. 

Munir Khan has studied the release and distribution of metal 

wear debris from metal on metal prostheses. Average size 

of the debris particles is 120 times smaller than a red blood 

cell. We found that this debris material is mostly concentrated 

in the extra-cellular portion of blood and that chromium has 

special affinity for plasma proteins. Therefore, measurements 

of plasma metal ion levels will provide more accurate results 

to compare release of wear debris in different hip prostheses. 

Moreover, our group was the first to show that metal ion levels 

increase following an hour of physiological exercise. 

The rise is of a few nanomoles that can only be picked if 

detection limits of the instrument are less than 1nmol/L. We 

found that determining the exercise-related cobalt rise is an 

accurate technique of determining in-vivo wear of metal on 

metal bearings, compared to resting plasma levels. 

We also studied the effects of metal ions on DNA. Using comet 

assay we found that cobalt and chromium ions caused 

DNA damage, which disappeared in the presence of apoptotic 

inhibitor. This apoptotic damage was misinterpreted as mutagenic 

in previous studies, but generally it is a safer thing for 

an agent to increase apoptosis. 

Our studies therefore echo the findings of epidemiologic studies 

in which researchers did not find a higher risk of cancer 

in patients with metal on metal bearing hip replacement at 

up to 30 years follow-up. 

METAL/METAL BEARING SURFACES: 

THE WAY OF THE FUTURE? 

Cecil H. Rorabeck, MD 

Health Sciencies Centre. 

London-Ontario (Canada) 

OBJECTIVE 

Polyethylene wear continues to be the most significant issue 

following total hip arthroplasty (THA) leading to the current 

increase in use of alternative bearing surfaces. We performed 

a prospective, randomized, blinded clinical trial comparing 

metal versus polyethylene bearing surfaces in patients receiving 

THA.



19


20 

METHOD 

Forty-one patients were randomized to receive a metal (23) 

or a polyethylene (18) insert with identical femoral and acetabular 

components. Patients were evaluated pre-operatively, 

at 3, 6, 12 months and annually thereafter, including an evaluation 

of erythrocyte and urine cobalt, chromium, and titanium, 

outcome measures (WOMAC, SF-12, Harris Hip Score) 

and radiographs. 

RESULTS 

No patients were lost to follow-up. At an average 7.2 (range 

6.1 – 7.8) years follow-up there were no differences in any 

outcome measures or radiographic findings. Patients receiving 

metal liners had significantly elevated metal ion measurements. 

At most recent follow-up erythrocyte cobalt levels 

were 7 times elevated (median 1.2 *g/L (metal) vs 0.18 *g/L 

(poly), p



21


22 

Los sistemas porosos conseguidos tienen una gran porosidad, 

entre el 66 y el 88% según la caracterización que hemos 

hecho de la misma mediante el método de desplazamiento 

de mercurio. El diámetro de los poros se halla entre 430 y 

650 ìm. La superficie de las trabéculas inter-poros tiene una 

morfología microscópica anfractuosa, estando quebrada por 

numerosas irregularidades de forma piramidal. 

Desde un punto de vista biomecánico las espumas de tántalo 

presentan dos grandes ventajas: su módulo elástico muy 

próximo al del hueso subcondral y la gran fricción que se 

produce entre la superficie exterior de la espuma y el hueso 

vecino, aproximadamente 1,5 vez mayor que con los sistemas 

clásicos de malla o de esférulas de titanio o de cobalto-cromo. 

Esas propiedades hacen que en experimentación animal se 

haya comprobado el relleno del 47% del volumen del sistema 

poroso por hueso a las 4 semanas, y del 75% al año, mucho 

mayor que lo visto para los sistemas clásicos ya mencionados. 

En el ser humano, mediante el estudio de implantes retirados 

tras una estancia en servicio en su interior, hemos podido 

comprobar que a los 8 días de su implantación ya se observa 

la deposición de fosfato de calcio amorfo recubriendo la 

superficie del metal trabecular (“Trabecular Metal”), que es 

como se ha denominado comercialmente el tántalo poroso, 

y reduciendo la luz de los poros del sistema en un 10%. En 

esa capa cálcica se produce la nucleación de cristales de 

hidroxiapatita, buen principio para una ulterior osteointegración. 

A las 6 semanas de la implantación, hay una aposición íntima 

del hueso a la superficie exterior del implante en un 

13,1±4,8% y una invasión por el hueso del 10,6±1,5% del 

sistema poroso, con una penetración en el mismo de hasta 

0,68-1,14 mm desde la superficie. Tras 6 meses, se evidencia 

un claro patrón de formación de hueso nuevo alrededor del 

63,3±9,4% de la periferia de las secciones estudiadas, con 

la invasión ósea de más del 50,7±10,4% del sistema poroso, 

penetrando hasta una profundidad entre 1,12 y 3,53 mm. 

Pasado el año, el hueso cubre en íntimo contacto hasta el 

87,6±7,4% de la superficie del implante, con un crecimiento 

de hueso en el 81,9±7,4% del interior del sistema poroso, 

llegando a penetrar todo el espesor del mismo. 

Esto se ve refrendado por el análisis de 263 casos de revisión 

de acetábulos fallidos de prótesis totales de cadera, por 

aflojamiento, con o sin osteolisis, desgaste y/o osteolisis con 

implante fijo, o inestabilidad articular con o sin conflicto fémoro-acetabular, 

utilizando el sistema de implantes acetabulares, 

cúpulas y suplementos, de metal trabecular, 

realizados entre julio del año 2000 hasta diciembre de 2002, 

por los Dres. Antonio Murcia, Agustín Blanco, Jorge Ballester, 

Antonio Meroño y el propio firmante. En 20 casos había un 

defecto tipo 1 de Paprosky (7,6%), en 73 un tipo 2A (27,7%), 

en 82 un tipo 2B (31,1%), en 39 un tipo 2C (14.,8%), en 40 

un tipo 3A (15,2%) y en 9 un tipo 3B (3,4%). Ha sido posible 

y fácil resolver el caso con la colocación estable de un cotilo 

monobloque TM mediante encaje a presión en la cavidad 

acetabular en el 90% de los acetábulos con un defecto tipo 

1 y en el 31% de aquellos con un defecto tipo 2. En el 63,5% 

de los tipos 1 y 2 hubo de implantarse una cúpula de revisión 

atornillada, al igual que en todos los casos con defectos del 

tipo 3. En un 13% de casos se añadieron suplementos de 

TM para reducir el gran defecto óseo existente y restaurar 

un reborde acetabular apto para anclar el componente a 

implantar. Estas condiciones se dieron en un 3,5% de casos 

con defectos de tipo 2, en el 55% de defectos tipo 3A y en 

el 100% de los de tipo 3B. Las cúpulas metálicas y los suplementos 

de tántalo pueden perforarse allá donde sea 

preciso y los suplementos se pueden tallar con facilidad, 

con instrumentos convencionales, para adaptarlos “a la medida” 

a los defectos en los que se aplican. 

El 100% de los casos permanecen estables en un seguimiento 

promedio de 74 meses, con un rango entre 5 y 7 años. 

No ha sido preciso revisar de nuevo ninguno por aflojamiento. 

No se han apreciado líneas radiotransparentes alrededor de 

las cúpulas en ningún caso y de los espacios vacíos que se 

observaron en el 14% de los casos inmediatamente a la 

intervención el 78% se habían rellenado totalmente y el 11% 

parcialmente durante el tiempo de seguimiento de la serie. 

Todo esto permite afirmar que el tántalo constituye un excelente 

material constitutivo de sistemas porosos, promocionando 

su integración e invasión por el hueso circundante 

incluso en situaciones complejas de déficit cuantitativo y 

cualitativo de éste, con defectos de contacto de hasta 5 mm 

de ancho. Su comportamiento a este respecto es sensiblemente 

mejor que los obtenidos con recubrimientos porosos 

de materiales como el cobalto-cromo o el titanio, con posibilidades 

limitadas de osteoconducción. Pero es que con el 

tántalo hay que plantearse, además de su demostrada capacidad 

de osteoconducción por las características estructurales 

del sistema poroso y por su excelente compati-bilidad 

mecánica y biológica, que su microtopografía super-ficial, 

que es clave para el tropismo, adhesión, expresión génica, 

diferenciación, morfología, proliferación y apoptosis celular, 

le concede una superficie bioactiva que podría incluso resultar 

osteoinductora. 

Con unos resultados clínicos prometedores e incógnitas aún 

por desvelar, el tántalo aparece como uno de los nuevos 

materiales más interesantes para su aplicación en cirugía 

ortopédica.



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24 

11.15 - 15.35 h 

CADERA / HIP 

Fijación de los componentes protésicos / Fixation of the prosthetic components 

Moderadores: Cecil Rorabeck, Luis Azorín 

CEMENTED OR CEMENTLESS FIXATION 

OF HIP IMPLANTS? 

Rudolph Geesink, MD PhD 

Professor of Orthopaedic Surgery, Maastricht University, 

Netherlands 

Both cemented and cementless results can yield excellent 

long term results, however each method has its potential 

problems and pitfalls that may render its use less attractive 

for an individual surgeon. 

Potential advantages of cementless fixation: 

- durable biological interface 

- simpler & more reliable technique (HA-coatings) 

- shorter operative time 

- fewer infections 

- preserves bone 

Potential issues with use of cement: 

- perfect cementing very difficult 

- cement-prosthesis surface undetermined 

- cement properties degrade with time 

- higher infection rate 

- more complications by fat embolism (especially elderly 

people). 

In the presentation the following differences will be discussed: 

- technique 

- time & cost 

- complications 

- interface biology 

- registry results 

Balancing both methods, cementless implantation of the 

third generation using HA-coatings has very substantial 

advantages and may result in excellent long term results, 

now documented past twenty years. 

ROLE OF THE CEMENT IN THE FIXATION 

OF THE PROSTHETIC COMPONENTS 


Princess Elisabeth Orthopeadic Hospital, 

Exeter (Great Britain) 

OSSEOINTEGRATION IN PRIMARY 

CEMENTLESS HIP FIXATION 

J. David Blaha, Ann Arbor 

University of Michigar Medical School, 

Michigan (USA) 

Many total hip systems are available to orthopaedic surgeons 

today. Many have good long term results in spite of apparently 

differing designs. From review of the literature available, the 

differing cementless designs have similarities that allow conclusions 

to be drawn as to the requirements for success in 

long term femoral component fixation. 

In the early 1980s, while the North American philosophy was 

very much driven by the philosophy of maximizing “fit and 

fill” by the use of “anatomic” stems with modular “sleeves” 

in the distal portion, European surgeons such as Karl Zweymüller 

and Lorenzo Sportono were exploiting an alternative 

idea – that of placing a wedge shaped prosthesis into the 

femur to obtain initial stability of the implant by press-fit. 

At the same time (i.e., the 1980s), North American designs 

were virtually universally produced with a porous coating into 

and through which bone was expected to grow to create an



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26 

interlock between implant and bone. The European designs 

had instead a roughened surface produced on a titanium 

alloy stem by “corundum blasting” the surface to a specific 

roughness but with out a specific porous coating. This 

treatment was expected to provide a surface onto which 

bone could grow to provide for long-term, secondary stability. 

There have been reports in the literature of successes with 

the Zweymüller and Spotorno (CLS) prostheses. With now 

more than 1,000,000 of these types of stems in place world 

wide, the clinical success of these tapered, wedge shaped 

prostheses suggests that this European philosophy is one 

that will continue into the decades to come. Survivorships in 

excess of 95% at as long as 20 years have been reported with 

no indication on radiograph of impending failure on the horizon. 

The results of these prostheses, coupled with the good results 

obtained with the AML type prostheses, suggest that 

we look at the similarities of the implants to discern the requirements 

for obtaining fixation of a femoral stem. The stages 

of fixation can be summarized as primary fixation, intermediate 

fixation and secondary fixation. 

- Primary fixation is that obtained in the operating room 

by driving a slightly oversized or wedge shaped implant 

into the bone. The interference of the stem in the bone 

leads to high pressure at the implant-bone interface and 

a “press-fit”. 

- Intermediate fixation is the means by which the implant 

remains stable while bone attaches itself to the implant 

for long-term stability. 

- Secondary fixation is that obtained by apposition of bone 

to a rough surface or apposition of bone to the surface 

and ingrowth into the depth of a porous coating. Interference 

probably disappears with bone remodeling and 

all long-term stability is from bone apposition to the surface 

of the implant. 

After secondary fixation is obtained the effects of bone loss 

through osteoporosis, fracture of the interface or debris or 

infection induced dissolution of the interface may cause an 

implant to become unstable in the bone. Continued postimplantation 

surveillance of implanted prostheses is imperative 

to determine the rate and potential solutions to late problems. 

Since different femoral components have similar results with 

respect to fixation, it is of more importance today to consider 

the functional restoration of a hip rather than the specifics of 

the stem. The surgeon should choose a stem with which he 

or she is comfortable and can reliably attain good primary 

fixation. Post operative care should take into account the 

shape and history of the stem so that the intermediate period 

can lead to osseointegration. 

In my practice, both porous coated and surface roughened 

implants have been successful in the long term. Having had 

to revise porous coated implants, particularly those that have 

achieved extensive ingrowth into porous coating in the diaphysis 

(such as the AML), I prefer the surface roughened alternative. 

REFERENCES 

Blaha JD: Pressfit Femoral Components in The Adult Hip Callahan 

JJ, Rosenberg AG and Rubash HE eds. 2nd ed. in press. 

BASIC SCIENCE OF HA-COATINGS 

Rudolph Geesink, MD PhD 


Netherlands 

Cementless fixation of hip implants has evolved through 

several stages of evolution since the last decades. Results 

of mechanical presfit implantation resulted in lack of adequate 

long term fixation. Unavoidable increase in micro-motion between 

the stiff implant and the more flexible bone during 

loading through difference in elastic modulus of both components 

resulted in unacceptably high loosening rates. More 

rigid fixation would be required between implant and bone 

to withstand all forces during daily activities. Second generation 

fixation using porous-coatings using beads or meshes 

represented a significant step forward although the interface 

biology was far from ideal. Both experimental and autopsy 

retrieval studies confirmed that average ingrowth surface of 

porous-coated implants rarely exceeded 10 - 15 % of available 

ingrowth surface. In clinical practice this may be adequate 

to provide long term stability, however the reliability of the 

system to provide durable fixation can easily be impaired by 

adverse actions of the surgeon such as accidental undersizing, 

varus positioning or adverse patient parameters such as 

impaired bone quality as in osteoporosis, rheumatoid arthritis 

or otherwise. Substantial increase in ingrowth fixation potential 

of implants can be achieved by providing HA-coatings in 

implant surfaces. HA-coatings of good quality should have 

both adequate mechanical and biological properties. 

Main advantages of HA-coatings in clinical practice: 

- reduce the time for implant fixation & rehabilitation 

- minimize relative motion between bone and implant 

- allow more normal physiological stress transfer 

- encourage gap filling between implant and bone 

- seal periprosthetic access channels for fluid & particles 

Results of experimental studies by many authors confirm the 

superior behavior of HA-coatings to achieve these goals 

while autopsy retrieval studies confirm improved results in 

clinical practice for a great variety of patient populations, including 

rheumatoid arthritis patients, patients suffering from 

osteoporotic bone or other adverse phenomena.



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28 

PRÓTESIS MODULAR CON 

HIDROXIAPATITA 

Antonio Navarro, Ricardo López 

Hospital Universitario de Traumatología Vall d’Hebrón. 


La principal diferencia entre la fijación cementada y la no 

cementada de los vástagos en prótesis de cadera, reside 

en la distribución de presiones en el intersticio metal-hueso. 

Con el uso del cemento se intenta obtener un reparto uniforme 

de la transmisión de fuerzas desde el vástago al tejido óseo 

circundante, mientras que con los sistemas no cementados 

existen zonas en las que no hay contacto con hueso, lo que 

evidenciaría el denominado “mito del press-fit”. 

La hidroxiapatita (HA) ha demostrado ser un muy buen 

material para el intersticio hueso-metal, presentando una 

serie de ventajas respecto a otros materiales. Por sus propiedades 

osteoconductivas, la osteointegración de los implantes 

es más rápida, presenta buena tolerancia al micromovimiento 

y es capaz de puentear distancias de salto mayores. 

Todo ello podría favorecer el press-fit en implantes no cementados, 

dejando de ser un mito. 

Nuestra experiencia en prótesis no cementadas recubiertas 

de hidroxiapatita ha sido satisfactoria, pero en ocasiones la 

morfología femoral no nos facilita la concordancia de tamaños 

entre la región metafisaria y la diafisaria, lo cual nos fuerza 

mucho en la elección del tamaño de la prótesis. Con el diseño 

de un implante femoral modular hemos conseguido mejorar 

la discordancia que a veces se producía debido a los 

diferentes tipos morfológicos. 

Desde abril del 2000 hasta noviembre del 2005 hemos 

implantado 283 vástagos modulares con buenos resultados 

clínico-radiológicos. El estudio por TC en 43 pacientes demostró 

la correcta osteointegración del implante, así como 

la distancia de salto que era capaz de osteoconducir la HA. 

CLINICAL AND HISTOLOGIC RESULTS 

RELATED TO A LOW-MODULUS 

COMPOSITE TOTAL HIP 

REPLACEMENT STEM 

Victor M. Goldberg, M.D;. Sam Akhavan, M.D.; Mary M. 

Matthiesen,Ph.D; Matthew Kraay, M.D.; Leah Schulte, 

BS; Clare Rinmac, Ph.D;Tom Penoyar, B.S. 

Case Medical Center, Department of Orthopaedics 

Cleveland, Ohio (USA) 

Osteolysis secondary to stress shielding in patients with a 

total hip arthroplasty has been attributed to greater stiffness 

of the prosthetic femoral stem compared with the stiffness 

of the femur. This concern led to the development of a composite 

femoral stem implant with a structural stiffness similar 

to that of the native femur. The stem consists of a cobaltchromium-alloy 

core surrounded by polyaryletherketone and 

titanium mesh for bone ingrowth. The purpose of this study 

was to determine the intermediate-term clinical, radiographic, 

and histologic results of the use of this stem. 

Twenty-eight patients (19 men and 9 women) with an average 

age of 51.3 years underwent primary total hip arthroplasty 

with the Epoch stem and were followed for an average of 

10 years. Harris hip scores were determined and radiographic 

studies were performed preoperatively, postoperatively, and 

at two year intervals thereafter. In addition, dual x-ray absorptiometry 

scans were made up to two years postoperatively 

to evaluate osseous resorption. Two femora obtained at 

autopsy 13 and 48 months after surgery were analyzed for 

bone ingrowth and ongrowth. 

The Harris hip scores averaged 56 points preoperatively and 

improved to 97 points at the time of the last follow-up. Dual 

x-rays absorptiometry scans demonstrated the greatest decrease 

in mean bone density (27.5%) in Gruen zone 7 at two 

years. Radiographs demonstrated no instances of migration, 

and only one hip had osteolysis. All stems had stable osseous 

fixation. One patient required revision of the acetabular component 

because of osteolysis. Histologic evaluation of the two 

femora that had been retrieved at autopsy at 13 and 48 months 

showed the mean bone ingrowth (and standard deviation) 

along the entire length of the stem to be 49.62% ± 13.04% 

and 73.57% ± 8.48%, respectively, and the mean bone ongrowth 

to be 54.18% ± 7.68% and 80.92% ± 6.06% respectively. 

Intermediate-term follow-up of hips treated with the Epoch 

stem indicated excellent clinical success, radiographic evidence 

of osseous integration, and histologic findings of osseous 

ingrowth and ongrowth. Although the implant has been associated 

with excellent results in both the short and the intermediate 

term, longer follow-up will be necessary to assess the 

long-term function of the implant.



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30 

ACETABULAR FIXATION-SEVERAL 

OPTIONS 

Aaron G. Rosenberg, MD 

Professor of Orthopaedic Surgery Rush Medical College. 

Chicago, Illinois (USA) 

Acetabular fixation in primary THA can be accomplished with 

bone cement as well as ingrowth techniques. However, cemented 

fixation has decreased dramatically in the U.S. due 

to the cementless components relative ease of insertion, the 

potential advantages of modularity on stability, and the relatively 

shorter surgical time required for insertion of ingrowth 

components. Cemented polyethylene sockets have proven 

durable with appropriate technique and indications and are 

inexpensive. Most recently, the phenomena of marrow embolization 

with the use of bone cement has come into question 

and so its use in the elderly or in patients with significant 

cardiopulmonary disease has been questioned. Certainly 

the effective use of cement requires the presence of appropriate 

bone stock and is more difficult in patients with multiple 

cysts or severely osteopenic bone. 

Cemented socket technique requires a relatively bloodless 

field (to achieve appropriate cement interlock into the underlying 

bone) and requires hypotensive anesthesia techniques. 

In general a mean arterial pressure of = 50 mmHg) is needed 

to allow for cement intrusion with pressurization. The technical 

requirements of the procedure makes attempts at less invasive 

surgical approaches more challenging. Excellent exposure 

is required for reaming, maintenance of a dry field and cement 

pressurization. Progressive circumferential reaming is performed 

until slight cancellous bleeding bone is noted over a 

substantative portion of the anterior and posterior columns. 

Medial cancellous bone is preserved for support of the implant. 

Fixation of a trial is not possible with this technique 

and this remains a potential drawback as well. Multiple small 

fixation holes in the dome in the area of the cancellous bone 

facilitate macro-interlock and the bone is cleaned with pulsatile 

lavage and dried. Cement is introduced into the bed and 

should be pressurized with an appropriate device. Details of 

cement use will vary on cement type but in general when 

doughy and no longer sticky the cup is inserted with a cup 

holder engaging inferiorly and then in a medial-superior 

direction to pressurize the cement further. Final positioning 

is achieved with the cup holder which must be used to apply 

pressure as the cement polymerizes. Cementing technique 

is crucial and the post operative radiographic appearance 

has been demonstrated to correlate highly with survival rates 

with poorly cemented sockets failing at a rate of 7x those 

that appear well fixed on initial radiographs. Ritter in 2004 admitted 

that despite a 30 year experience in cementing sockets 

he was unable to achieve consistent post-operative x-ray 

appearances regarding the cement mantle. Given the experiential 

learning curve that most orthopedic surgeons face 

with cemented fixation of the acetabular cup component, the 

role of the cemented socket in THA today appears rela-tively 

limited. 

Predictable biologic fixation involves two aspects: the implant 

and host response. The implant requisites include a biologically 

friendly surface, intimate host bone-implant apposition, 

and rigid implant stability. The host involves a process of 

biologic incorporation similar to fracture healing which includes 

the formation of hematoma adjacent to the porous substrate 

which then undergoes a transformation from fibrous tissue 

to women bone and ultimately to mature lamellar bone. Conditions 

which alter the biology of bone may influence the predictability 

of press fit fixation. These conditions include severe 

metabolic bone disease (i.e.-osteomalcia), irradiated bone, 

and metastatic disease. 

The process of reaming is essentially similar with reaming 

to the point where subchondral bone is exposed and healthy 

bleeding host bone is visualized. The acetabular bed is inspected 

for cysts and soft tissue such as retained labrum 

which might interfere with socket seating. The ultimate size 

implant to insert is based upon surgeon preference with most 

surgeons adopting a “press fit” by relatively under reaming 

the socket by 1-2 millimeters in reference to the actual implant 

size. Controversy regarding the need for supplemental fixation 

techniques (spikes or screws) remains an issue but is probably 

only significant when bone stock is anatomically distorted or 

mechanically insufficient. 

In cases of dysplasia as well as protrusio, the cementless 

socket has proven useful and easier to insert than the cemented 

socket. The isolated protrusio defect implies loss of 

medial wall bone, but in general remaining bone stock is adequate 

for use of a hemispherical ingrowth acetabulum. This 

is done by reaming up to a larger size that fills the acetabular 

remnant from the top (ilium) to the bottom (ischio-pubic ramus) 

and has good support from the posterior and anterior columns. 

Reaming does not proceed medially! The rim is reamed up 

to accept a component that will sit on the rim. Depending on 

the degree of protrusio, a variable amount of bone loss will 

be present medialy. Reverse reaming of graft taken from the 

femoral head is used to fill the defect. In the rare case where 

a cemented acetabulum is chosen, more definitive bone 

grafting of the medial wall defect may be required. This can 

be done by layering slices of the femoral head medially, 

buttressing the bone slices against the rim of the protrusio 

defect and supplemented with particulate bone. 

Ingrowth socket use has made the performance of total hip 

arthroplasty in the patient with dysplasia much easier to perform 

with two available methods: anatomic placement (at 

the level of the teardrop) with bulk autologous or allograft 

bone graft placed superiorly if the socket is insufficiently 

covered or placement at a higher hip center. The higher hip



31


32 

center is only recommended when the dysplastic process 

has led to remodeling of adequate bone to support the implant 

in this position-most commonly Crowe II. Leg length discrepancy 

must be kept in mind and appropriate intervention on 

the femoral side made as needed. Crowe III or IV defects 

are best treated by bringing the socket to its anatomic location. 

Several acetabular component designs have incorporated 

the use of a hydroxyapatite (HA) coating to improve bony 

ingrowth or ongrowth. Hydroxyapatite is an osteoconductive 

material that in animal models, has been shown to optimize 

bone attachment to fixation surfaces. The most popular initial 

designs that incorporated an HA coating were smooth, 

hemispherical components that relied on a press-fit for obtaining 

initial implant stability without screws for fixation. 

Unfortunately, these components have been associated with 

poor intermediate term results as with time, the HA resorbed 

and without a biological surface available for osseointegration 

to occur, aseptic loosening ensued. In one comparative study 

of porous coated cups, HA coated smooth press-fit acetabular 

components and HA coated threaded screw in cups, the 

highest rate of failure (11%) was seen with the HA coated, 

smooth press fit cup at a minimum of five years. In response 

to the problems of early failure, HA has since been applied 

to grit blasted and porous coated implants with acceptable 

results at short and intermediate term follow-up. One clinical 

trial that compared a titanium fiber metal mesh component 

with and without HA coating among 23 pairs of patients. Although 

the clinical results were similar, the components with 

HA coating were associated with less migration and fewer 

radiolucencies when studied with radiostereometry analysis. 

No clear clinical benefits were identified. Similar animal 

studies have suggested that HA applied to a titanium fiber 

mesh coating enhances early bone ingrowth but there may 

not be a longer-term benefit in terms of overall implant stability. 

A potential concern with the use of HA coatings is that 

as the HA delaminates with time, these particles may enter 

the joint space causing damage to the bearing surface. 

CEMENTED CUPS: RESULTS AND 

TECHNIQUE 




THREADED CUPS, WHEN? 


Orthopädische Krankenhaus Gersthof 

Wien (Austria) 

INTRODUCTION 

Although very popular in the late seventies and early eighties 

of the last century, threaded cups are scarcely used today, 

because the outcome achieved with their first generation 

was poor. We introduced in 1985 a new generation of threaded 

cups. From 1993 a further development was used. The 

aim of this study was to analyse the minimum 10 years results 

with this cup and to compare the results with those 

obtained with hemispheric cups. 

MATERIAL AND METHODS 

Between January 1993 and June 1994 400 patients (412 

hips) were provided with primary implantations in our department. 

After excluding other combinations than ceramicpolyethylene 

and the previously used Alloclassic system this 

left a group of 365 patients (376 hips) provided with the Biconcup 

and SL-Plus-stem. No other cementless system was 

used and no implants inserted during that period were cemented.One 

hundred sixty-one patients (167 hips, or 72%) 

had idiopathic osteoarthritis, 37 patients (38 hips, 16.4%) 

had developmental dysplasia, 11 patients (11 hips, 4.7%) 

had osteonecrosis of the femoral head, 10 patients (10 hips, 

4.3%) had post-traumatic arthritis, and six patients (six hips, 

2.6%) had other abnormalities. In all cases, we used cementless 

threaded cups in combination with straight cementless 

stems with a double taper made of hot forged titanium 

alloy (Plus Orthopedics AG) and a ceramic ball head (Ceramtec, 

Plochingen, Germany) in contact with an ultrahighmolecular-weight 

PE liner (Plus Orthopedics AG). The cup 

shells were made of commercially pure titanium. The surface 

was roughened through grit blasting. The mean surface 

roughness was 5 µm; therefore, no coating was applied.225 

patients (232 hips) were followed clinically and radiologically. 

The age of the patients was 19.8 – 83.3 years at operation, 

mean 62.6, the follow-up time was 10.0 – 13.1 years, mean 

10.3. We also evaluated gaps on postoperative radiographs. 

Two types of gaps were distinguished. The first type involved 

incomplete bony coverage of the metal cup shell in Position 

1 (ie, between the cranial circumference of the implant and 

the iliac bone). Usually triangular, these gaps were called 

cranial dead space or triangular cranial gaps. Their appearance 

on 10-year followup radiographs was compared with the 

postoperative radiographs to see whether they had become 

smaller or were obliterated by newly formed bone. The second 

type were gaps between the front end of the implant and the 

acetabular floor. Because these were measurable on the 

monitor-controlled radiographs, they were determined in 2-



33


34 

mm steps and evaluated in comparison with the postoperative 

radiographs to see whether they had become smaller spontaneously 

or had been obliterated. 

RESULTS 

Two patients of the overall group (376 hips) were reoperated: 

one because of an early infection and one because of cup 

breakage. No polyethylene liner was exchanged because of 

wear or inestability. The radiographic analysis showed tilting 

into the valgus-position in 2 patients, into the varus-position 

in 1. These 3 cup shells were radiographically loose at the 

follow-up. The surrounding bone stock showed progressive 

osseointegration in 134 implants, in 91 cups the bone reaction 

was indifferent, 2 cups showed integration and some atrophy, 

1 cup stable fibrous ingrowth. In 1 case a severe osteolysis 

was found. In this case after the end of the study an exchange 

of the PE-liner as well as of the ball head was done. The 

cup was stable and left in place. The Kaplan-Meier survival 

rate with revision for any reason was 99.3% (95%, CI: 96.9% 

– 99.8%) after 10 years. The survival rate with revision for 

any reason and radiologic loosening was 98.6% (95%, CI: 

96.0% - 99.5%) at 10 years. Triangular cranial gaps were 

present postoperatively in 50 hips (21.5%). The gaps tended 

to spontaneously fill by newly formed bone. Thirty-six of 

these gaps (72%) were completely obliterated at the 10-year 

followup. Gaps between the metal shell and the acetabular 

floor were present in 47 hips (20.3%) postoperatively. In 

thirty-seven of these hips (78.7%), the gaps measured 0 to 

2 mm. Nine patients had gaps of as much as 4 mm and one 

of as much as 6 mm. These gaps also tended to be spontaneously 

obliterated. The two valgus migrations were 

associated with newly formed gaps in Position 2. 

CONCLUSION 

Implant survivorship was comparable to the best published 

10-year survival rates with the Harris-Galante and other 

types of hemispheric cups, however with an encouragingly 

low rate of complications related to the PE liner observed in 

our series.. The exclusive use of this implant in all indications 

for primary hip replacement demonstrated that the results 

of the Bicon Cup will be beneficial in almost all cases including 

difficult hips.In the next decade it needs to be determined 

whether the fixation method of the metal cup shell in the 

pelvis and the stability of the PE-liner in the metal-PE-interface 

of the study device will lead to lower occurrence of osteolysis 

and an improved longevity. 

CEMENTLESS CUP: LESSONS FROM 

RETRIEVAL STUDIES 

Jorge O. Galante, Robert Urban 

Rush Arthritis & Orthopaedic Institute 

St. Luke’s Medical Center, 

Illinois (USA) 

Histopathological findings were reviewed on retrieved autopsy 

specimens for the purpose of identifying the causes of long 

term failure. 

The study group consisted of twenty four primary porouscoated 

Ti acetabular cups (HG1 or HG II) retrieved at autopsy 

5 to 21 years after implantation. 

All specimens exhibited bone ingrowth with more bone present 

at the components rim and in the vicinity of screws. The 

extent was 35% (7 to 70%). 

Particles within granulomas were present within holes and 

in the rim in all components. 

Expansion of granulomas through the screw holes into the 

periprosthetic bone was obvious in the longer term specimens. 

Granuloma penetration was deeper along screw tracts extending 

often through the whole length of the screw. Screw 

holes with or without screws were the main pathway for extension 

of granulomas into the retroacetabular bone. 

Pelvic granulomas increased from a few millimeters at 5 to10 

years to ballooning massive lesions at longer follow up, most 

often not visualized on plain radiographs. In all of the long 

term cases there was invasion of the interface and of the 

porous coating itself. 

The mean volumetric wear rate was 47 mm3/yr. Damage to 

the back side of the liner was moderate. 

The mechanism responsible for long term failure is related 

to wear and granuloma formation. 

These phenomena can lead to massive pelvic osteolysis and 

or eventual loosening by invasion of the porous coating by 

granuloma as the actual causes of failure.



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36 

15.50 - 19.35 h 

CADERA / HIP 

Doble cúpula y vástago corto / Resurfacing and short stem 

Moderadores: Rafael González Adrio, James Richardson 

RESURFACING TOTAL HIP 

ARTHROPLASTY: AN EMERGING 

TECHNOLOGY 

Cecil H. Rorabeck, MD FRCSC 

Health Sciencies Centre, 

London-Ontario (Canada) 

Historically, the results of surface replacement have been 

poor; however, one needs to examine the reasons for this. 

The sockets were thin and made of high density polyethylene 

and were cemented. They frequently loosened. Also, avascular 

necrosis of the femoral head leading to collapse occurred. 

This was often related to patient selection, surgical 

technique or combination thereof. The most unique problem 

identified with surface replacement was fracture of the neck 

of the femur which could occur with notching. Thus, in summary, 

during the 1970’s and 1980’s resurfacing was associated 

with a small incidence of femoral neck fracture, a small incidence 

of collapsed femoral heads and a major problem with 

large head metal polyethylene wear leading to massive 

polyethylene induced osteolysis, cup loosening and failure. 

Newer hip resurfacing designs (e.g. BHR) will eliminate many 

of these problems because of the large head metal on metal 

bearing surfaces. Metal/metal bearings have been around 

for almost 30 years and it is clear that osteolysis, with metal 

on metal, is very rare and it equally clear that large heads, 

provided polar contact is used, work very well. Thus, the newer 

metal-metal resurfacings allow the surgeon to insert the 

acetabulum cementless and the newer generation instrumentation 

has enabled the surgeon to insert the femoral component 

in a reproducible manner with minimal risk to notching etc. 

The UK experience with the BHR resurfacing hip began in 

1997 and at 5-years demonstrated no heterotopic ossification, 

no radiolucent lines, and no cup migration; however, there 

was a question of minor migration of the femoral component 

or perhaps stress shielding of the proximal femur. Subsequently, 

independent RSA studies demonstrated, out to 24 

months, minimal change in position of the femoral component 

and the acetabular component. Similarly, dexa scan data 

have, if anything, shown an improvement in bone mineral 

density in Zone 7, when compared to conventional total hip 

replacement. 

Is the risk for metal ion exposure to patients with a metalmetal 

resurfacing THR any different from contemporary metalmetal 

THR? While whole blood levels of cobalt and chromium 

are elevated with metal-metal articulations, nonetheless, these 

levels appear to be acceptable and in some cases, have 

been shown to diminish with time. 

What are the clinical results of contemporary metal-metal resurfacing 

THR? Some of the earlier reported series indicated 

higher revision rates at 5-years than traditional hip replacement. 

For example, McMinn (1996) reported a 4% revision rate at 

5 years in 235 hips. Similarly, Amstutz had a similar revision 

rate at 3-5 years using his metal-metal resurfacing device. 

More recent data, however, would suggest that while failures 

of resurfacing hip arthroplasty can occur, nevertheless, the 

incidence of fracture of the femoral neck has been reduced 

substantially, although it will never be completely eliminated. 

McMinn, reporting his experience of 2,385 Birmingham THR’s, 

notes 27 patients needed to be revised at a 5-year follow 

up. These included 10 for femoral neck fracture and a further 

8 for either AVN or collapse of the femoral head. Thus, while 

these complications have not been totally eli-minated in 

metal-metal resurfacing THR, nonetheless, the incidence is 

extremely low. Similarly, data from the Australian Joint Replacement 

Registry would indicate the incidence of femoral 

neck fracture to be less than 1%. 

Clearly, patient selection is important for resurfacing arthroplasty. 

In our Center we reserve the operation for patients 

60 years of age or younger with normal bone stock and do 

not recommend it for patients with inflammatory arthritis. 

In conclusion, contemporary results in metal-metal resurfacing 

replacement have been excellent and it is clearly a bone conserving 

operation. In prospective trials, the mind-term results of 

metal-metal resurfacing are at least as good as traditional THR. 

While the potential for neck fracture with resurfacing athroplasty 

is present, a review of the literature indicates that if 

it is going to occur it is most likely to do so within the first few 

months. Metal-metal resurfacing arthroplasty of the hip is 

best indicated today in non-inflammatory arthritis and in patients 

of less than 60 or individuals with a normal dexa scan.



37


38 

REFERENCES 

- Ebied A, Jouneaux SF, Pope JA. Hip resurfacing arthroplasty: 

The Liverpool experience. International Conference 

Engineers and Surgeons – Joined at the Hip (2002 June) 

- Glyn-Jones S, Gill HS, McLardy-Smith P, Murray DW. 

Roentgen stereophobgrammetric analysis of the Birmingham 

hip resurfacing arthroplasty: A 2-year study. J Bone Joint 

Surg Br (2004 March) 86B:172-6. 

- Treacy RB, McBryde CW. Pynsent PB. Birmingham resurfacing 

arthroplasty. A minimum follow up of 5 years. J Bone 

Joint Surg BR (2005 February). 87(2): 167-70 Oswestry 

Worldwide. FDA Review Memo, page 59. 

CURRENT STATUS OF HIP 

RESURFACING-WHAT HAVE WE 

LEARNED 

Harlan C. Amstutz, MJ Le Duff 

Joint Replacement Institut, 

Los Angeles (USA) 

INTRODUCTION 

Hip resurfacing is currently the fastest growing hip procedure 

worldwide. 

MATERIALS AND METHODS 

We reviewed 1000 hips in 838 patients who received a 

Conserve® Plus resurfacing at a single institution. The average 

age of the patients was 50.0 years with 74.7% male. 

Etio-logies included: idiopathic osteoarthritis (70%), osteonecrosis 

(6.5%), trauma (6%), developmental dysplasia (11%), 

child-hood disorders (LCP and SCFE - 4%), rheumatoid 

disease (2%) and others (0.5%). The hips were resurfaced 

irrespective of femoral defect size, etiology or BMI. Technique 

changes were based on retrieval analysis and were instituted 

to opti-mize bone preparation and initial fixation. This included 

in-creasing the area for cement fixation using multiple 3mm 

(one-eighth inch) drill holes into both the dome and chamfered 

areas, especially where the bone was sclerotic, complete 

removal of cystic material and improved the cleansing and 

drying of the bone prior to cementation. 

RESULTS 

Mean follow-up was 5.6 years (1.1 to 11.0). All clinical scores 

improved significantly (p



39


40 

HOW SMALL CHANGES IN CEMENT 

TECHNIQUE CAN HAVE A BIG INFLUENCE 

IN HIP RESURFACING 

Dr H.P. Delport* and Dr T. Scheerlinck** 

* Department of Orthopaedic Surgery, AZ Waasland, Sint 

Niklaas, Belgium 

** Department of Orthopaedic Surgery, UZ Brussel, 

Laarbeeklaan 101, 1090 Brussels, Belgium 

According to a study by Amstutz et al. 1 , failure of the femoral 

component of hip resurfacings is related to a varus position 

of the implant, a small area of implant fixation and the presence 

of large femoral head cysts. From that study it is clear 

that initial implant fixation is critical. Although our mid-term 

clinical results are promising, we reported 7 failures out of 

750 hip resurfacings. Five of them were early trans-cervical 

femoral fractures. In cooperation with Prof M Morlock from 

Hamburg, we analysed our retrieved failures and inspected 

the bone-cement interface after sectioning of the femoral 

head. Although the ReCap femoral component was designed 

with a 0.5 mm clearance for the cement mantle, we found 

a much larger actual cement mantel due to large quantities 

of cement pressurised into the reamed cancellous bone and 

femoral head cysts. This was associated to some degree of 

bone necrosis. Similar findings have been reported by Pat 

Campbell et al. 2 . 

Hip resurfacing is a difficult procedure in which the femoral 

neck is at risk. Technical details such as avoiding excessive 

load to seat the femoral head, avoiding uncovered weak 

reamed cancellous bone and controlling the cement mantle 

thickness, are important. Excessive cement penetration could 

impair the blood supply and cause high peak temperatures 

during cement curing. Both factors could lead to necrosis of 

the reamed head and promote fractures. Hence the recommendations 

of R. Gill and K. De Smet 3 to control the temperature 

at the bone-cement interface by irrigation during 

cement curing. 

To our knowledge only Rudi Bitsch from the group of Thomas 

Schmalzried performed research on the effect of the 

cementing technique in hip resurfacing 4 . They developed a 

laboratory model based open-cell reticulated carbon foam 

to mimic the cancellous bone of the reamed femoral head. 

Using that model they evaluated the effect of different cementing 

techniques on the cement mantle thickness. We 

developed a bovine cancellous bone model and compare 

five different cement application techniques using low- and 

medium-viscosity cement. Using a CT scan based technique 

developed by Thierry Scheerlinck, and plastic resurfacing 

head replicas, we were able to quantify the cement mantle 

within the reamed femoral head without cutting the speci- 

mens. That technique allowed us to determine among others: 

the amount of cement penetration into the cancellous bone, 

the cement mantle thickness and the amount of air trapped 

between the cement and the implant. Our preliminary findings 

suggest that the amount of cement pressurised into the 

reamed femoral head is strongly influenced by the cementing 

technique. Low-or high-viscosity cement poured into the 

resurfacing implant resulted in a high degree of cement penetration 

but small quantities of air trapped between the 

implant the cement. On the other hand, applying cement on 

the reamed head and implanting a resurfacing head that 

does not containing any cement, allowed a better control of 

the cement mantle thickness but resulted in more air trapped 

between the cement and the implant. 

CONCLUSION 

The requirements of the cement mantle of resurfacing heads 

might be very different from those of cemented femoral hip 

stems. In hip resurfacing, a cement mantle thickness of 3 

mm or more is probably not necessary and even deleterious. 

A large cement mass or a thick cement layer may lead to 

thermal necrosis or block the blood supply of the femoral 

head. Using a bovine model and a CT scan based measurement 

technique, we found that only manual cement application 

on the reamed femoral head, without any cement in 

the resurfacing implant, resulted in an even cement mantle, 

without “overstuffing” the reamed cancellous bone with cement. 

REFERENCES 

1. Amstutz, H. C., Le Duff, M. J., Campbell, P. A., Dorey, F. 

J. The effects of technique changes on aseptic loosening 

of the femoral component in hip resurfacing. Results of 

600 Conserve Plus with a 3 to 9 year follow-up. J Arthroplasty. 

22:481-489, 2007. 

2. Campbell, P., Beaule, P. E., Ebramzadeh, E., Leduff, M., 

De Smet, K., Lu, Z., Amstutz, H. C. The John Charnley 

Award: a study of implant failure in metal-on-metal surface 

arthroplasties. Clin Orthop. 453:35-46, 2006. 

3. Gill, H. S., Campbell, P. A., Murray, D. W., De Smet, K. 

A.: Reduction of the potential for thermal damage during 

hip resurfacing. J Bone Joint Surg [Br]. 89-B:16-20, 2007. 

4. Bitsch, R. G., Heisel, C., Silva, M., and Schmalzried, T. 

P. Femoral cementing technique for hip resurfacing arthroplasty. 

J Orthop Res. 25:423-431, 2007.



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42 

HIP RESURFACING FOR 

OSTEONECROSIS 

Harlan C. Amstutz, MJ Le Duff 

Joint Replacement Institute, 

Los Angeles (USA) 

INTRODUCTION 

The results of THA and prior hip resurfacing designs with 

Polyethylene in osteonecrosis (ON) have been less satisfactory 

than for patients with other etiologies. Metal-on-metal 

(MM) resurfacing is bone preserving and stable and permits 

a wide selection of revision options for young patients. 

METHODS 

From a cohort of 1000 hips of all etiologies, 84 hips (70 patients, 

avg. age 40.1 years), with ON Ficat Stage III (19 hips) 

and IV (65 hips) were treated with hybrid MM resurfacing. 

81% were males and 19% female. 33.3% had previous surgeries 

including core decompressions (17 hips), hemi-resurfacing 

arthroplasty (3 hips), pinning (5 hips), free vascularized 

fibula graft (2 hips) and Judet graft (1 hip). 71 hips (85%) 

presented femoral head defects larger than 1cm and none 

were excluded because of the size of the defect. 

RESULTS 

The average F/U was 6.2 years (1.5-11). Average femoral 

component size was 46.3mm. The clinical scores were comparable 

to that of the rest of the cohort except for the activity 

score which was lower in average (7.0 vs.7.5, p=0.0015). 

Three hips were revised: 2 for femoral loosening at 22 and 

61 months, and one for a fracture of the acetabular wall (over 

reaming in osteopenic bone) with protrusio of the cup one 

day post surgery. There were no other complications. X-ray 

analysis revealed 3 cases of neck narrowing (1 bilateral) and 

2 cases of femoral radiolucencies in 3 zones around the 

metaphyseal stem. The Kaplan-Meier 5-year survival estimate 

was 97.1% (95% Confidence Interval 88.7 to 99.2). There 

has been no femoral component loosening for patients implanted 

after August of 1997. 

CONCLUSION 

Our results highlight that the etiology of osteonecrosis itself 

does not constitute a contraindication for resurfacing despite 

large defects. Technique is critical in achieving initial femoral 

fixation and promoting long-term durability. Those patients 

who had large defects are advised to refrain from impact 

activities. 

AVASCULAR NECROSIS AND HIP 

RESURFACING 

Michael Menge, Clemens Nitschke 

St. Marienkrankenhaus, 

Ludwigshafen (Germany) 

BACKGROUND 

Osteonecrosis (AVN) of the femoral head very often affects 

patients between the age of 20 and 50 years of age. In many 

cases conservative treatment will not be sufficient and 

arthroplasty has to be performed. As in these mostly younger 

patients life expectancy will be normal it may be helpful using 

a resurfacing device first to keep standard total hip replacement 

as a second chance procedure. 

Method: Between 1999 and 2006 more than 1.500 patients 

received a MoM resurfacing of the hip. From those patients 

35 patients received a resurfacing for a stage four posttraumatic 

or localized AVN. We excluded patients with metabolic 

disorders or continued steroid medication. There were 

two additional cases of sickle cell anaemia. The technique 

in these cases will be described and the problems will be 

discussed. 

RESULTS 

The intraoperative findings and the technique will be demonstrated. 

Mostly the neck of the femur will have to be shortened 

significantly. Lateralizing the acetabular socket can partially 

retain the offset. Only two patients had to be revised due to 

neck fracture according to progressive necrosis. 

CONCLUSIONS 

In our limited series of AVN treated with resurfacing of the 

hip the outcome was better than in standard hip THR. In 

about 6% the osteonecrosis progressively lead to a neck 

fracture and to conversion to a standard stem with big head 

metal to metal articulation. 

RESURFACING IN THE 

ELDERLY PATIENT 

Michael Menge 


Ludwigshafen (Germany)



43


44 

INDICATIONS AND RESULTS OF 

CHILDHOOD DISORDERS 

(DDH,SCFE,LCP) WITH THE CONSERVE® 

PLUS HIP RESURFACING 

Harlan C. Amstutz, MD 

Joint Replacemente Institure. Los Angeles (USA) 

From our initial series of 1000 hips (838 patients), 145 hips 

(127 patients) received a Conserve® Plus resurfacing for 

arthritis secondary childhood disorders. The average age of 

the patients was 44.9 (range, 15 to 68). 58.3% were female. 

103 hips were DDH, 4 epiphyseal dysplasia, 21 LCP, and 

17 SCFE. 22 hips (15.2%) had previous surgery. There were 

18 with bilateral resurfacings; 10 one-stage, and 8 two-stage 

with an average of 23 months between surgeries (range 3.9 

- 95.3 months). 

The clinical results have been very good and survivorship 

comparable to other etiologic groups. Range of motion normalized 

in DDH and there was comparable improvement in 

the other groups. There have been no socket failures. Leg 

lengths have equalized in the majority and only 2 had a 

residual discrepancy greater than 1 cm. Femoral failures were 

associated with early technique in patients with small 

component size and or large cystic defects. There have 

been no failures in the last 7 years. There have been 9 healthy 

babies born to 5 mothers resurfaced after OA secondary 

to DDH and the average age at the time of surgery for these 

women was 34.0 years (range 23.0-39.1). 

The dysplastic hip is challenging for hip resurfacing mainly 

because of the abnormal acetabular anatomy. The native 

acetabulum is shallower, often with a deficient anterior wall. 

In hip resurfacing with the Conserve® Plus socket, adjuvant 

fixation was not necessary, thus assessment of the acetabular 

reamed cavity and careful placement of the socket are paramount. 

Medialization of the socket is often necessary to improve 

lateral coverage. Furthermore, because both the femoral 

neck and acetabulum may be excessively anteverted, hip 

stability may be compromised unless adjustments are made. 

Preoperative planning is essential to avoid intra- and postoperative 

complications and to promote long-term durability 

after replacement. An assessment of the length of the femur 

can be made by pelvic leveling with various size blocks being 

placed under the short leg. It is not possible to lengthen more 

than 2 cm and this length must be obtained by bringing the 

socket as close as possible to the anatomical acetabulum. 

The early clinical results with the Conserve® Plus metal-onmetal 

surface arthroplasty in Crowe I and II DDH did not 

meet our initial expectations although the porous coated socket 

fixation has been excellent. While the incidence of 

femoral neck fracture and femoral component loosening was 

higher than desired initially, we have been able to lessen 

the risk of femoral loosening and neck fractures by improved 

femoral bone preparation and fixation including cementing 

the stem in patients with risk factors. 

Patients with LCP and SCFE present a different type of 

challenge: a low head to neck ratio, usually with short neck 

length, and an abnormal position of the head relative to the 

neck make it difficult to resurface without violating the integrity 

of the neck, increase leg length, and orient the components 

to avoid impingement. In addition, patients have often undergone 

a previous surgery when they present for resurfacing 

and pre-existing hardware may be present that cannot be 

removed. In our early experience a medial notch to the 

femoral neck was necessary because of low head-neck ratio 

in order to resurface without reaming too much acetabular 

bone. However, now the availability of the thin (3.5mm) shell 

allows a substantial gain in femoral component diameter and 

it has not been necessary to notch the neck. Unless there 

was significant impingement after trial reduction, we have 

not removed osteophytes anteriorly or laterally especially 

when the osteophyte contains “structural” bone and in absence 

of the normal cortex. In patients with a short neck, evaluate 

the external rotation of the hip in extension. Limitation of 

motion may be due to impingement of the greater trochanter 

against the ischium. The posterior ridge of the greater trochanter 

might have to be removed flush with the neck with 

an osteotome to increase the external rotation. Although hip 

resurfacing is a technically difficult operation in these patients, 

our results to date have been encouraging with only 2 conversions 

to THR (1 patient) out of 38 operated hips. 

CONSIDERATION ON SURGERY AND 

PROSTHETIC DESIGN IN RESURFACING 

ARTHROPLASTY OF THE HIP 

Reinhold Ganz 

Orthopädische Universitätsklinik Balgrist, 

Zürich (Switzerland) 

The application of metal-on-metal bearings to hip resurfacing 

arthroplasty has lead to a substantial and worldwide increase 

of this type of hip prosthesis, especially in the younger age 

group. Although reports on short term results are encouraging, 

femoral loosening and femoral neck fractures are of ongoing 

concern. In this context, a controversial debate is going on 

with regard to the remaining perfusion of the femoral head 

after the posterior surgical approach and after the preparation 

of the femoral head for fixation of the cup. Some evidence for



45


46 

a disturbed blood supply, coming from retrieval analysis is 

challanged by the high number of well functioning hips after 

this type of approach and technique of application. Ho-wever 

more recent and dynamic measurements of the the femoral 

head perfusion clearly show a dramatic decrease of the blood 

supply when the mentioned approach and technique is used; 

this disturbance may well play a role for the longevity of the 

implant. 

Another essential problem of the actual metal-on-metal resurfacing 

prostheses is the clearence for motion, which is inferior 

to classic THR. The most critical factor in this regard is the 

ratio of the head/neck diameters and the limitations for improvement. 

As result of the technically reduced motion, impingement 

could be identified. Impingement is primarily a clinical 

problem, but it has gained increasing interest as factor for 

prosthesic loosening. 

For a next generation of resurfacing implants improvement 

of the approach and of the technique of application may optimize 

the femoral head perfusion. Furthermore surgical steps 

but also design aspect of the prosthetic components are proposed 

to overcome the impingement problems of actual 

prostheses. 

RESURFACING VERSUS TRADITIONAL 

ARTHROPLASTY 




MIDTERM RESULTS OF A FEMORAL 

PRESERVING STEM 


Endo-Klinik, 

Hamburg (Alemania) 

THE RATIONALE, SURGICAL TECHNIQUE 

AND RESULTS OF USING SHORT, 

METAPHYSEAL STEMS IN THA. SHORT 

STEMS, THE NEXT GENERATION OF 

IMPLANTS IN THA 


Northwestem University Feinberg School 

of Medicine Chicago, 

Illinois (USA)



47

Miércoles, 9 de abril 

Wednesday, 9th April 

CADERA / HIP 

Abordajes quirúrgicos: MIS y Navegación 

Cadera difícil y complicaciones de las artroplastias 

Cadera de revisión 

Surgical approach: MIS and Navigation 

Difficult hip and complications 

Hip revision 

Moderadores / Moderators: Luis López-Durán, Humbert Ferrer, 

Francisco Gomar, Antonio Coscujuela

MIÉRCOLES / WEDNESDAY 

50 

08.00 - 08.45 h 

CADERA / HIP 

Abordajes quirúrgicos: MIS y Navegación / Surgical approach: MIS and Navigation 

Moderador: Luis López-Durán 

MIS THR: WHY, HOW AND RESULTS 

Lawrence D. Dorr, M.D. 

Medical Director Arthritis, 

Institute Centinela Hospital, 

California (USA) 

The biggest controversy in total hip replacement (THR) in 

2007 is the size of the incision for the operation. Minimally 

invasive surgery (MIS) exploded onto the orthopedic scene 

in the early 2000s. Although some surgeons, such as Keggi, 1 

Sculco, 2 and Lester 3 had been performing surgery with small 

incisions, it was a change that was far below the radar screen. 

The explosion occurred when Richard Berger refined the 

two-incision technique and combined this with a new pain 

management protocol to send patients home the day of 

surgery. 4 There was a segment of the patient population that 

embraced this concept and the knowledge of this option of 

care spread rapidly among the lay-community until the “tipping 

point” was quickly passed. 5 Surgeons then began to feel 

pressure to provide this care to patients. 

Surgeons resented the fact that this change occurred “upside 

down,” ie, patients knew about this MIS, and wanted it, before 

the surgeon knew, and certainly before the surgeon knew 

whether it was medically effective. Popularity preceded publication! 

Many surgeons questioned the wisdom of making 

changes in an operation that was proven to improve quality 

of life and be of benefit to society. 6 The decade of the 1980s 

had seen change in fixation from cemented to noncemented, 

and the decade of the 1990s provided changes in the 

articulation surface. These changes gained acceptance 

(cementless fixation slowly over 15 years) because the surgeon 

could appreciate the contribution of the changes to 

better durability for the patient. In the decade of the 2000s, 

the surgeon has had deep reservations about changing the 

incision, which could possibly create more complications 

and more stress for the surgeon in performing the operation. 

On the other hand, surgeons performing these small-incision 

operations observed the improved optimism and recovery 

in their patients and quickly became advocates. The research 

into MIS has focused on learning why small-incision operations 

benefit patients. 

PURPOSE OF MIS 

Any change which occurs quickly, and without documentation, 

will create misunderstanding. The purpose of MIS operations 

is to enhance the recovery of the patient. It was recognized 

by those who pioneered it that it was a short-term benefit 

change. It achieved increased confidence in the patient in 

their recovery, which resulted in earlier discharge from the 

hospita 1,4,7 earlier return to work, 4,8 fewer assistive devices 

for more rapid mobilization, 4,7,8 and less pain? 7 Because the 

publications that documented this medical effectiveness 

lagged behind its community popularity, confusion among 

surgeons occurred. Every previous change in THR was done 

to prolong the durability of the operations. Many surgeons 

assumed this change in incision length likewise was to improve 

durability. Because this was not the purpose, the 

surgeons never did, and never will, find evidence that increased 

durability was possible. The short-term benefits are 

important to the patient and stimulate some of the underserved 

population for total hip and total knee replacement 

to seek an operation. 9 Some patients fear hospitalization 

because of concerns with infection and medical errors. Some 

patients, who are still economically productive, are fearful of 

loss of a job or a business with a prolonged recovery. Elderly 

patients will choose not to undergo surgery because they 

their life span against an expected long recovery. 10,11 Most 

patients do not want to go to a rehabilitation unit, and the 

ability to go home from the hospital tilts their decision to 

undergoing the operation because it gives them return of 

their independence and prevents postoperative depression. 

12-14 The greatest benefit of MIS THR is that it has created 

a new process of THR that benefits the patient’s mental 

health and confidence in achieving the outcomes they 

envision. 15 

BENEFITS OF MIS 

Complete success of THR requires that patients achieve relief 

of pain, return of function and mobility, and satisfaction. Medical 

effectiveness of THR is rated by scoring instruments 

such as Harris Hip Score 16 and SF-36, 17 which grade pain 

relief and functional gains. The deficiencies of these instruments 

are that they measure functional gains we as 

surgeons deem important, but not necessarily the functional 

activity the patient considers most important. Furthermore, 

we do not have a grading system for satisfaction. Hudak and 

co-workers 18 defined satisfaction as the patient being unselfconscious 

about their repaired limb (hip). In a personal 

communication, David Beverland of Belfast, Ireland, terms



51


52 

this the “forgotten hip,” which means that the patient has forgotten 

that he had an operation. Our data with the posterior MIS 

indicate that this can be found in 80% of these patients. 15 

The short-term benefits of MIS include earlier satisfaction 

with the operation, better initial confidence in the outcome, 

and a more rapid early recovery because of higher expectations, 

less anxiety, and greater optimism. 13-15,18,19 Patients 

expect that they will more quickly regain control of their 

independence and be able to manage themselves and their 

world. Both of these expectations, when fulfilled, are of highest 

importance in patients achieving satisfaction with their 

operation. 20-21 

Improved satisfaction is of no benefit if the complication rate 

of the patient is increased. Woolson and coworkers 22 suggested 

that a posterior mini-incision was not safe. These data 

have never been confirmed, and all randomized 2,7,23 and 

other comparative studies have reported that it is a safe operation. 

The lead surgeon in the Woolson study was Christopher 

Mow, who is now an advocate of the operation (personal 

communication). There has never been any confirmation of 

the Woolson data that posterior MIS operations are not safe, 

and therefore these operations should be considered safe. 

There are 19 citations in the literature that document safety 

of the posterior mini-incision operation. 

The primary complication reported with small-incision 

operations, whether posterior, anterior, or two-incision, has 

been femoral fracture. 22,24-26 What is not established is 

whether this fracture rate is greater than with long incisions. 

In published randomized series, there is no difference in 

fracture occurrence. 2,7,23 In comparative studies of both 

posterior and anterior approaches, a difference has been 

found only in the Woolson study. 22 Only Pagnano and 

coworkers 27 and Duwelius et a 18 have compared two-incision 

to posterior mini-incision procedures, with no significant 

differences in fractures (although Pagnano only had fractures 

with the two-incision procedure). The percentage of fractures 

in small-incision series must be compared with the percentage 

that occurs with traditional incisions. Berend and coworkers 28 

reported 1.3% fractures in 1959 uncemented hips with posterior 

long incisions and 6.3% in 476 hips with uncemented 

stems with anterior long incisions. These data would suggest 

that mini-incision operations do not have an increased fracture 

rate. Likewise, other complications, such as infection and 

dislocations, have not shown statistical difference; Kim 29 

suggests increased infection on a single case without any 

statistical scientific data. 

HOW IMPORTANT IS MIS? 

The new process of THR includes changes in incisions, pain 

management, and recovery patterns. The author believes 

most surgeons credit the pain management program for the 

improved patient benefits. It has a huge contribution to the 

improved outcomes. Patients could not go home the same 

day of surgery without pain control. Patients could not participate 

in an active physical therapy program without avoi- 

dance of nausea, vomiting, and lethargy caused by parenteral 

narcotics. So, physicians who credit the pain management 

program may well be correct. Patients, however, in the author’s 

experience credit the small incision, because it is objective, 

visual evidence to them that their body was minimally 

injured, and they credit this confidence to their improved 

recovery. 15 Therefore, the small incision is an integral “team 

member” of the success of the new process for THR. There 

has not yet been any reported success with outpatient THR 

using long incisions. 

The success of the pain management program is founded 

on the avoidance of parenteral narcotics. Berger and coworkers 

4 initiated this idea. Our success with our modifications 

of this program reports low pain scores, near elimination 

of emesis, and elimination of severe complications of respiratory 

depression, cognitive changes, gastrointestinal ileus, 

and a low rate of urinary retention. 30 The keys to success 

with this program are preemptive oral medications (elimination 

of patient-controlled analgesia and epidural opiates) and 

the intraoperative wound injection. Pain scores of 2 to 3 on 

an analog scale of 0 to 10 emphasize the success of this 

program for patients. 30 In our randomized study of posterior 

mini versus long incisions, using this pain program, patients 

with a small incision had statistically lower pain scores. 7 We 

now have the experience of sending 200 patients home the 

day of surgery (using the posterior mini approach we have 

described 31 ) without a single readmission or complication 

from this same-day discharge. 

Recovery is accelerated by the use of an active rather than 

a passive physical therapy program. 7 A passive physical 

therapy program treats all patients the same, and an active 

physical therapy program tailors the progress of the patient 

according to the capability of that individual. The use of passive 

physical therapy programs has been a weakness of randomized 

and comparative studies in attempting to differentiate 

between the effects of small and long incision. We used 

an active physical therapy program in our randomized study 

of posterior incisions, and patients with small incisions outperformed 

those with long incisions by earlier discharge and 

more patients going home on a single assistive device. 7 The 

new process of THR provides improved patient care, and MIS 

has been an important contributing factor to this process. 

SUMMARY 

MIS operations will continue to increase in popularity of use 

among surgeons. Increasing data have overcome the fears 

of decreased safety. When the operation is performed 

correctly, just as when long-incision operations are performed 

correctly, the outcomes are the same 2,7,23 In the author’s 

experience, when the two other parts of the new process of 

THR are used (pain management without parenteral narcotics 

30 and an active recovery program 7 ), patients with 

posterior MIS have better in-hospital recovery. A psychological 

study 15 shows the mental benefits of MIS are strongest at 

6 weeks postoperative and, although less so, remain influential 

to patients at 6 months to 1 year.



53


54 

There are no data that indicate one small incision is better 

than another. Comparative studies of posterior mini-incisions 

to two-incision operations do not show superiority for pain 

and show conflicting data for functional differences. 8,27 The 

anterior “no muscle cut” incisions likewise have shown no 

superiority. Berger has not been able to achieve same-day 

surgery discharge with the anterior incision as he achieves 

with the two-incision operations (personal communication). 

Duwelius and coworkers 8 also had earlier discharge with the 

two-incision patients. A cadaver study suggests the anterior 

and posterior small incisions have similar muscle damage 

because of retraction force with the anterior incision. 32 Clinical 

results are not better in anterior incisions than published for 

posterior incisions, 12,23,26 and no randomized studies have 

been reported with anterior incisions. It would seem that 

surgeons who operate posteriorly should remain posterior, 

and those who do so anteriorly should continue to do so. 

This will eliminate the risk of additional stress for the surgeon, 

and complications, which would be present in changing the 

operative approach in addition to the incision length. 

Surgeons must accept the change in patient attitude, which 

has been the quintessential feature of the MIS experience. 

Today’s electronic age exponentially expands the patient’s 

community network through which they seek and gain knowledge 

for their health care. 11,12,19 Patients form expectations 

and develop optimism and decisiveness to overcome their 

disability if they gain information that gives them hope of 

regaining quickly their control of their social world. 14,18 Optimism 

and education will encourage the underserved patients to 

overcome their fears and elect to undergo the operations. 

10,11,14,19 The surgeon must learn the expectations of 

each patient and strive to fulfill their goals. 13,14,20,21 If goals 

are unrealistic, the surgeon must take the time to direct the 

patient to acceptable achievable goals. Each surgeon must 

weigh the risk-to-benefit ratio of MIS THR for each patient 

based on surgical skill and experience, the culture of his/her 

community, and the mental health of the patient. 

REFERENCES 

1. Kennon RE, Keggi JM, Wetmore RS, et al: Total hip arthroplasty 

through a minimally invasive anterior surgical 

approach. J Bone Joint Surg Am 85:39-48, 2003 (suppl 4) 

2. Chimento GF, Pavone V, Sharrock N, et al: Minimally invasive 

total hip arthroplasty: A prospective randomized 

study. J Arthroplasty 20:139¬144, 2005 

3. Floren M, Lester DK: Durability of implant fixation after 

less-invasive total hip arthroplasty. J Arthroplasty 21:783- 

790, 2006 

4. Berger RA, Jacobs JJ, Meneghini RM, et al: Rapid rehabilitation 

and recovery with minimally invasive total hip 

arthroplasty. Clin Orthop Relat Res 429:239-247, 2004 

5. Gladwell M: The Tipping Point: How Little Things Can Make 

a Big Difference, 2002 

6. Laupacis A, Bourne R, Rorabeck C, et al: The effect of elective 

total hip replacement on health-related quality of life. 

J Bone Joint Surg Am 75:1619-1626, 1993 

7. Dorr LD, Maheshwari, Long WT, et al: Early pain and 

functional results comparing minimally invasive to conventional 

total hip arthroplasty: A prospective, randomized 

blinded study. J Bone Joint Surg Am 89:1153¬1160, 

2007 

8. Duwelius PJ, Burkhart RL, Hayhurst JO, et al: Comparison 

of the 2-incision and mini posterior total hip arthroplasty 

technique. J Arthroplasty 22:48-56, 2007 

9. Hawker GA, Wright JG, Coyte PC, et al: Differences between 

men and women in the rate of use of hip and knee 

arthroplasty. N Engl J Med 342:1016-1022, 2000 

10. Clark JP, Hudak PL, Hawker GA, et al: The moving target: 

A qualitative study of elderly patients’ decisionmaking 

regarding total joint replacement surgery. J Bone 

Joint Surg Am 86A:1366-1374, 2004 

11. Hudak PL, Clark JP, Hawker GA, et al: “You’re perfect 

for the procedure! Why don’t you want it?” Elderly arthritis 

patients unwillingness to consider total joint arthroplasty 

surgery: A qualitative study. Med Decis Making 22:272- 

278, 2002 

12. Inaba Y, Dorr LD, Wan Z, et al: Operative and patient 

care techniques for posterior mini-incision total hip arthroplasty. 

Clin Orthop Relat Res 441:104-114, 2005 

13. Mahomed NN, Laing MH, Cook EF, et al: The importance 

of patient expectations in predicting functional outcomes 

after total joint arthroplasty. J Rheumatol 29:1273-1279, 

2002 

14. Orbell S, Johnston M, Rowley D, et al: Cognitive representations 

of illness and functional and affective adjustment 

following surgery for osteoarthritis. Soc Sci Med 

47:93-102, 1998 

15. Don LD, Thomas D, Long WT, et al: Psychologic reasons 

for patients preferring minimally invasive total hip arthroplasty. 

Clin Orthop Relat Res 458:94-100, 2007 

16. Harris WH: Traumatic arthritis of the hip after dislocation 

and acetabular fractures: Treatment by mold arthroplasty. 

An end-result study using a new method of result evaluation. 

J Bone Joint burg Am 51:737¬755, 1969 

17. Ware JE Jr, Sherboume CD: The MOS 36-item shortform 

health survey (SF-36). I. Conceptual framework 

and item selection. Med Care 30:473-483, 1992 

18. Hudak PL, McKeever PD, Wright JG: Understanding the 

meaning of satisfaction with treatment outcome. Med 

Care 42:718-725, 2004 

19. Mancuso CA, Salvati EA, Johanson NA, et al: Patients’ 

expectations and satisfaction with total hip arthroplasty. 

J Arthroplasty 12:387-396, 1997 

20. Bischoff-Ferrari HA, Lingard EA, Losina E, et al: Psychosocial 

and geriatric correlates of functional status after 

total hip replacement. Arthritis Rheum 51:829-835, 2004 

21. Chamberlain K, Petrie K, Azariah R: The role of optimism 

and sense of coherence in predicting recovery following 

surgery. Psychology and Health 7:301-310, 1992 

22. Woolson ST, Mow CS, Syquia JF, et al: Comparison of 

primary total hip replacements performed with a standard 

incision or a mini incision. J Bone Joint Surg Am 86, 

2235-2244, 2004



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56 

23. Oganda L, Wilson R, Archbald P, et al: A minimal incision 

technique does not improve early postoperative outcomes: 

A prospective randomized controlled trial. J Bone Joint 

Surg Am 87:699-700, 2005 

24. Archibeck MJ, White RE Jr: Learning curve for the twoincision 

total hip replacement. Clin Orthop Relat Res 

429:232-238, 2004 

25. Bal BS, Haltom D, Aleto T, et al: Early complications of 

primary total hip replacement performed with the two incision 

technique. J Bone Joint Surg Am 11:2432-2438, 2005 

26. Matta JM, Shahrdar C, Ferguson T: Single-incision anterior 

approach for total hip arthroplasty on an orthopaedic 

table. Clin Orthop Relat Res 441:115-124, 2005 

27. Pagano MW, Trousdale RT, Meneghini RM, et al: Patients 

preferred a mini-posterior THA to a contralateral twoincision 

THA. Clin Orthop Relat Res 453:156-159, 2006 

28. Berend ME, Smith A, Meding JB, et al: Long term outcome 

and risk factors of proximal femoral fracture in uncemented 

and cemented total hip arthroplasty in 2551 hips.J 

Arthroplasty 21:53-59, 2006, (suppl 2) 

29. Kim YH: Comparison of primary total hip arthroplasties 

performed with a minimally invasive technique or a standard 

technique: A prospective and randomized study. J 

Arthroplasty 21:1092-1098, 2006 

30. Maheshwari AV, Boutary M, Yun AG, et al: Multimodal 

analgesia without routine parenteral narcotics for total hip 

arthroplasty. Clin Orthop Relat Res 453:231-238, 2006 

31. Dorr LD: Hip arthroplasty, minimally invasive techniques 

and computer navigation. (ed 1). Philadelphia, PA, Saunders 

Elsevier, 2006 

32. Meneghini RM, Pagnano MW, Trousdale RT, et al: Muscle 

damage during MIS total hip arthroplasty: Smith-Peterson 

versus posterior approach. Clin Orthop Relat Res 

453:293-298, 2006 

MIS VERSUS STANDARD POSTERIOR 

APPROACH IN HIP RESURFACING 

Michael Menge 



INTRODUCTION AND AIMS 

Most patients don’t ask for the length of the scar but want 

to gain normal function of the operated joint. In the last years 

in many countries surgeons propose so called “minimal invasive 

surgery” (MIS) but there still is the question if the patient 

will benefit from these technically more difficult procedures. 

MIS may have advantages but there may be a higher risk of 

disadvantages due to the restricted visual field and therefore 

an increased overall complication rate (AAHKS 2004). 

METHOD 

In our institution we minimized the dorsal approach of the 

resurfacing procedure. The objective was not to obtain a 

cosmetically pleasing small scar but lesser invasive disruption 

of functional tissue, shorter time of exposition of the 

wound, less blood loss, and fewer complications. In lean patients 

the length of the scar (one-incision) will be around 10 

cm, in obese patients the approach will afford 12 to 15 cm. 

There is no need for special instrumentation. The procedure 

and the after-treatment will be demonstrated stepwise. 

RESULTS 

In the meantime the minimal invasive surgical dorsal approach 

proved to be superior to the standard approach regarding to 

the duration and the postoperative of the procedure. All anatomical 

structures are fully visible at the corresponding preparation 

steps and there is no need for computer-assisted 

navigation. The patients had less blood loss, less pain, faster 

recovery, and fewer complications. Drains or preoperative 

hemodilution were abandoned. 

CONCLUSION 

After six months there are no differences in the clinical results. 

But with minimal access surgery the patient will have advantages 

beside of a shorter scar (no transfusions, no drains, 

lesser risk of infection, faster rehabilitation). There is no higher 

rate of complications. Thus the minimal access surgery 

can be recommended to surgeons familiar with the procedure 

of resurfacing from the posterior approach. 

THR: COMPUTER NAVIGATOR, 

COMBINED ANTEVERSION AND LARGE 

HEADS 


Medical Director Arthritis Institute Centinela Hospital, 


The method of using combined anteversion rather than a target 

value for cup placement is becoming more prevalent in the 

search by Total Hip Arthroplasty (THA) surgeons for methods 

of minimizing the risk of impingement. In this concept, anteversion 

is considered an additive property of both the femoral and acetabular 

components. An abnormal femoral anteversion may 

be compensated by making an appropriate adjustment of the 

acetabular anteversion. The acetabular cup anteversion is based 

on an accurately determined femoral anteversion with 

compensation made for the outlier femoral anteversion. 

The computer allows the surgeon to absolutely know the position 

of the components within an accuracy of 1 degree and 

precision of 5 degrees. By better precision of component



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58 

placement, and employing the combined anteversion method, 

the occurrence of impingement should significantly be reduced 

and this will improve the immediate and long-term results 

for total hip replacement. 

Fewer studies have explored femoral component malposition 

than acetabular component malposition. Femoral malposition 

is thought to be more easily avoidable intraoperatively, and 

is more difficult to assess postoperatively by standard radiographs. 

McCollum& Gray thought the orientation of the femoral 

component as less critical and less complex than the 

orientation of the acetabular component. It was believed that 

the femoral anteversion can always be controlled to the desired 

position of 10-15 degrees. Surgeons therefore implant 

the acetabular cup targeting a fixed angle of anteversion based 

on the assumed femoral anteversion. 

The surgeon can control the amount of anteversion of a cemented 

stem but not of a noncemented stem. Anteversion 

of cemented stems can be controlled by the surgeon because 

a stem with a diameter smaller than that of the medullary 

canal of the femur can be used and can be inserted into 15 

+/- 5 degrees of anteversion while being fixed with cement. 

The surgeon has much less ability to control anteversion of 

a cementless femoral stem because the rigid metal stem 

must be fit into a specific geometric shape of the femur. The 

anterior bow of the femoral diaphysis, which can be as much 

as 10 degrees, influences the anteversion of the pros-thetic 

stem. Anteversion has been found to show an inverse relationship 

with the degree of femoral bowing. 

D’Lima et al., in their finite-element study found the femur 

has variable anteversion of the neck and variable anterior 

diaphyseal bowing, both of which influence the anteversion 

of the prosthetic neck in relation to the femoral axis. With 

use of postoperative computed tomography scans, Wines 

and McNicol, with both cemented and cementless stems, 

found a range of 15 degrees of retroversion to 45 degrees 

of anteversion (mean of 16.8 degrees) and Pierchon et al., 

with cemented stems, reported a similar observation with 

range of 30 degrees of retroversion to 37 degrees of anteversion 

(mean of 16.5 degrees). 

In our institute, using imageless computer navigation, we 

found a mean of 9 degrees of anteversion of the femoral 

stem in men and a mean of 19 degrees in women. Our finding 

is similar to that of Maruyama et al. who measured intact 

cadaver femora to have a mean anteversion if 9.8 

degrees. In our patients, cementless stem position is between 

10-20 degrees anteversion in only 43% of hips; 10% are in 

absolute retroversion; 42% between 0-9 degrees anteversion; 

and 5% have more than 20 degrees anteversion. The mean 

anteversion for cementless stems was 8-10 degrees. This 

data means that there is the potential for cementless stem 

anteversion to be 15 degrees different than the anticipated 

position of 15 degrees anteversion. Therefore, the risk exists 

that the stem may have an outlier of 10 degrees, and if the 

cup does too, the combined anteversion could be 20 degrees 

than anticipated. 

Ranawat taught a ‘manual combined anteversion test for total 

hip replacement since the early 1990s. According to him, 

with the cup and stem in place, the lower limb is positioned 

in neutral (or slight hip flexion) and is internally rotated until 

the femoral head is symmetrically seated (coplanar) in the 

cup. The combined anteversion is the amount of internal rotation 

in degrees needed to produce a coplanar head and cup. 

Ranawat and Maynard recommended a combined anteversion 

of approximately 45 degrees in female patients, and 20 degrees 

to 30 degrees in male patients. McKibbin defined the 

stability index for anatomic hips to be 30 degrees to 40 

degrees, with a range of 20 degrees to 35 degrees for men 

and 30 degrees to 45 degrees for women. A combined anteversion 

of



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60 

if the stem anteversion is 10-20 degrees, the cup anteversion 

should be 20 degrees, whereas if the stem anteversion is 5 

degrees, the cup anteversion should be close to 30 degrees. 

We rarely exceed 30 degrees of cup anteversion because 

exceeding 30 degrees increases the risk of impingement in 

external rotation and abduction and extension in external 

rotation. 

REFERENCES 

1. Barrack, R. L.: Dislocation after total hip arthroplasty: 

implant design and orientation. J Am Acad Orthop Surg, 

11(2): 89-99, 2003. 

2. D’Lima, D. D.; Chen, P. C.; and Colwell, C. W., Jr.: Optimizing 

acetabular component position to minimize impingement 

and reduce contact stress. J Bone Joint Surg 

Am, 83-A Suppl 2 Pt 2: 87-91, 2001. 

3. D’Lima, D. D.; Urquhart, A. G.; Buehler, K. O.; Walker, 

R. H.; and Colwell, C. W., Jr.: The effect of the orientation 

of the acetabular and femoral components on the range 

of motion of the hip at different head-neck ratios. J Bone 

Joint Surg Am, 82(3): 315-21, 2000. 

4. Dorr LD: Hip arthroplasty. Minimally invasive techniques 

and computer navigation, 1st edition. Philadelphia, PA, 

Saunders Elsevier, 2006. 

5. Dorr, L. D.; Malik, A.; Wan, Z.; Long, W. T.; and Harris, 

M.: Precision and Bias of Imageless Computer Navigation 

and Surgeon Estimates for Acetabular Component Position. 

Clin Orthop Relat Res, 2007 Dec; 465:92-9. 

6. Jolles, B. M.; Genoud, P.; and Hoffmeyer, P.: Computerassisted 

cup placement techniques in total hip arthroplasty 

improve accuracy of placement. Clin Orthop Relat Res, 

(426): 174-9, 2004. 

7. Kalteis, T.; Handel, M.; Bathis, H.; Perlick, L.; Tingart, M.; 

and Grifka, J.: Imageless navigation for insertion of the 

acetabular component in total hip arthroplasty: is it as 

accurate as CT-based navigation? J Bone Joint Surg Br, 

88(2): 163-7, 2006. 

8. Lucas DH, S. R.: The Ranawat sign. A specific maneuver 

to assess component positioning in total hip arthroplasty. 

J Orthop Tech., 2: 59-61, 1994. 

9. Malik, A., and Dorr, L. D.: The science of minimally invasive 

total hip arthroplasty. Clin Orthop Relat Res, 463: 74-84, 

2007. 

10. Malik, A.; Maheshwari, A.; and Dorr, L. D.: Impingement 

with total hip replacement. J Bone Joint Surg Am, 89(8): 

1832-42, 2007. 

11. Maruyama, M.; Feinberg, J. R.; Capello, W. N.; and D’Antonio, 

J. A.: The Frank Stinchfield Award: Morphologic features 

of the acetabulum and femur: anteversion angle and implant 

positioning. Clin Orthop Relat Res, (393): 52-65, 2001. 

12. McCollum, D. E., and Gray, W. J.: Dislocation after total 

hip arthroplasty. Causes and prevention. Clin Orthop Relat 

Res, (261): 159-70, 1990. 

13. McKibbin, B.: Anatomical factors in the stability of the hip 

joint in the newborn. J Bone Joint Surg Br, 52(1): 148- 

59, 1970. 

14. Parratte, S., and Argenson, J. N.: Validation and usefulness 

of a computer-assisted cup-positioning system in 

total hip arthroplasty. A prospective, randomized, controlled 

study. J Bone Joint Surg Am, 89(3): 494-9, 2007. 

15. Pierchon, F.; Pasquier, G.; Cotten, A.; Fontaine, C.; Clarisse, 

J.; and Duquennoy, A.: Causes of dislocation of total 

hip arthroplasty. CT study of component alignment. J Bone 

Joint Surg Br, 76(1): 45-8, 1994. 

16. Widmer, K. H., and Zurfluh, B.: Compliant positioning of 

total hip components for optimal range of motion. J Orthop 

Res, 22(4): 815-21, 2004. 

17. Wines, A. P., and McNicol, D.: Computed tomography 

measurement of the accuracy of component version in total 

hip arthroplasty. J Arthroplasty, 21(5): 696-701, 2006. 

18. Yoshimine, F.: The safe-zones for combined cup and neck 

anteversions that fulfill the essential range of motion and 

their optimum combination in total hip replacements. J Biomech, 

39(7): 1315-23, 2006.



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62 

09.00 - 14.00 h 

CADERA / HIP 

Cadera difícil y complicaciones de las artroplastias / Difficult hip and complications 

Moderadores: Humbert Ferrer, Francisco Gomar 

MANAGEMENT OF THE PAINFUL HIP OF 

THE YOUNG ADULT 

Reinhold Ganz 



The vaste majority of hip symptoms in young adults can be 

attributed to acetabular dysplasia or femoroacetabular impingement. 

The best treatment fort he hip with acetabular dysplasia is 

a reorientation procedure. Frequently the insufficiently shaped 

anterior head-neck contour needs to be additionally corrected 

to avoid secondary impingement even with a perfectly 

corrected acetabulum. This is even more importand in a borderline 

dysplastic acetabulum which is symptomatic from 

impingement even before surgery; Radial arthro-MRI may 

be helpful in the precise evaluation of such hips. The result 

of a reorientation procedure depends on the achieved spatial 

positioning of the acetabulum, on the joint congruency but 

also on the amount of joint damage at the time of surgery. 

Hips without a labral lesion have a better longterm prognosis. 

The treatment of femoroacetabular impingement focuses on 

improving the clearence for hip motion. On the acetabular 

side local or general overcoverage is trimmed. If possible 

the labrum is refixed for better lubrication and early clinical 

and radiological results clearly favor labrum refixation over 

resection. On the femoral side an osteochondroplasty is performed 

resecting all nonspherical parts of the head and reestablishing 

a normal offset between head and neck. Experience 

has shown that the results are better with early surgical intervention. 

While complex morphological abnormalities are best 

treated with surgical dislocation, more isolated pathologies 

are more and more treated arthroscopically. Arthroscopy however 

needs advanced experience to avoid collateral damage; 

for a combined acetabular and femoral correction the 

procedure takes longer than open surgery. 

HIP ARTHROSCOPY FOR 

FEMORO-ACETABULAR IMPINGEMENT 


Warwick Medical School, 

Coventry (Great Britain) 

CHARNLEY LFA IN THE TEENAGER. 

FOLLOW-UP TO 34 YEARS 

B M Wroblewski, P D Siney, P A Fleming 

The John Charnley Research Institute, Wrightington Hospital, 

Hall Lane, Appley Bridge Near Wigan (Great Britain) 

Between 1962 and 2004, 42 primary Charnley low-frictional 

torque arthroplasties (LFAs) in teenagers were carried out at 

Wrightington Hospital. 

Patients mean age at surgery was 17 years 10 months (12 

– 19) and the underlying hip pathology was juvenile rheumatoid 

arthritis, developmental dysplasia of the hip, protrusio or 

ankylosing spondylitis. 

Smaller or non-standard components were commonly used 

in both the acetabulum and the femur. 

There were no post-operative complications. 

Pain relief was consistently achieved but improvement in 

function was limited by the underlying pathology. At a mean 

follow-up of 14 years 5 months (2 – 34), 16 LFAs (38.1%) 

had been revised with aseptic cup loosening in 13 cases 

(31%) being the main problem. 

Clinical results of the Charnley LFA in teenagers are successful. 

The limiting factor is the acetabular bone stock.



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64 

TOTAL HIP REPLACEMENT WITH ALL 

ALUMINA BEARINGS IN PATIENTS UNDER 

30 YEARS OF AGE 

Laurent Sedel, Remy. Nizard, Agnes Raoult , Damien 

Pourreyron, Frederic Zadegan. 

Hopital Lariboisière, APHP , University Denis Diderot, 

Paris (France) 

Total hip arthroplasty in very young age is very challenging 

due to long term expectancy necessary at this age, and also 

due to special aetiology in this group of patients; Anatomical 

difficulties at the femur and at the acetabulum side are 

frequent. 

Alumina on alumina sliding couple was introduced to address 

the problem of macrophagic reaction to wear debris. Then 

this material is particularly dedicated to young and active 

patients. We looked retrospectively at this category of patients 

in order to see if this choice was right. 

MATERIALS AND METHODS 

From a population of more than 4500 total hips implanted 

with an all alumina bearings couple we selected 132 prostheses 

in 101 patients aged less than 30 years at time of 

operation. These prostheses were implanted consecutively 

since September 1979. Fifty nine males, 42 females, mean 

age was 23 (12 to 30). 

Avascular necrosis was the more frequent aetiology: 64 

cases (51 steroid induced), followed by inflammatory diseases: 

18, postrauma: 18, sequellae of infection in the newborn 

10, slipped capital epiphysis in 12, miscellaneous in 10 (sickle 

cell anaemia, tumours, agenesis of the femur) .Twenty four 

hips had had some previous procedure. 

Regarding the implanted material, the stem (Ceraver Osteal*) 

was cemented 62 times and uncemented in 70. there was 

5 different alumina socket fixation systems: 10 bulky cemented, 

22 bulky cementless, 6 with a screw in titanium cup and 

alumina liner, 14 press fit titanium shell covered with a 

titanium mesh, and 80 comparable but with an outer surface 

rough and covered with hydroxyapatite... Alumina head was 

always 32 mm in diameter except one and all prostheses 

had an alumina on alumina couple. 

RESULTS 

Six patients (8 hips) deceased, 17 hips were revised at a 

mean of 9 years postop. leaving 107 hips with a 7 years 

mean follow-up (1 to 27 years). Socket revisions were 

performed 12 times, femur was revised twice and bipolar 

revision 3 times (two for sepsis). Regarding the 107 hips still 

in place, clinical results ( regarding Postel Merle D’Aubigné 

rating system) was excellent or very good ((16 to 18)) in 97, 

good (13 to 15) in 9 and fair or bad in1. four became pregnant 

without problems. Roentgenographic results, 7 had some 

radio lucent lines, one was complete . On the femur side, 10 

had limited osteolytic lesion always on cemented stem and 

in zone 7 (Gruen). Survivorship analysis depicted 82% survivors 

at 10 years and 72% at 14 years. Interestingly enough 

infection, avn (with the exception of sickle cell disease) and 

inflammatory diseases did better than trauma or slipped 

capital epiphysis. . 

DISCUSSION AND CONCLUSION 

In a difficult series of patients under the age of 30 years, the 

results of alumina on alumina total hip were satisfactory. 

Most of the failures were related to surgical difficulties. Socket 

fixation system was not optimised at the beginning explaining 

the high rate of acetabular component loosening. There was 

also a tendency for some aetiologies to give bad results, this 

was the case for sickle cell disease ((3 failures out of 8) and 

for slipped capital epiphysis (3 out of 12). Last cementless 

design markedly improved prosthesis stability. Socket 

revisions were relatively easy and limited to this component. 

Interestingly enough, previous infected cases (10 cases) 

were not complicated with infection recurrence in this series. 

PROTESIS TOTAL DE CADERA Y 

ENFERMEDAD DISPLÁSICA DE CADERA 

A. Murcia Mazón. M. Fernández Fairén, RP. García Díaz. 

Universidades de Oviedo y Politécnica de Cataluña, 

Hospital de Cabueñes, Gijón (Spain) 

INTRODUCCIÓN 

La displasia de cadera en el adulto (DCA) es secundaria a 

la enfermedad luxante de la cadera durante la época de 

crecimiento. Suele tratarse de una forma de displasia residual, 

que afecta a la articulación y que es responsable de una 

artrosis precoz y cuya frecuencia oscila entre el 25 y 50% 

de los menores de 50 años 1 . En otras ocasiones la DCA se 

descubre con motivo de un estudio Radiológico por otra 

patología 2 . 

INDICACIONES 

La artroplastia total de cadera (ATC) en una DCA es una 

intervención difícil y para conseguir un cotilo cubierto por 

completo por hueso es necesario implantarlo en su sitio 

original 3 con frecuencia realizar una osteotomía subtrocantérica 

de acortamiento. 

La planificación de la ATC en una displasia exige establecer 

una clasificación donde la altura en que se encuentra la 

cabeza femoral es más importante que determinados ángulos



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66 

a nivel acetabular o femoral. Existen diversas clasificaciones; 

la de Eftekhar que establece cuatro grados.: dos caderas 

bajas (A y B) con acetábulo plano, poco profundo, ovalado, 

con arreglo al grado de anteversión de la extremidad proximal 

del fémur y la forma de la cabeza femoral. La pared anterior 

es más fina que la posterior que está engrosada. 

Los grados C y D corresponden a las luxaciones altas y la 

hemipelvis correspondiente es pequeña y las estructuras 

óseas son delgadas y osteopróticas. El acetábulo original 

es rudimentario y lleno de tejido graso. En la mayoría de los 

casos el soporte óseo más importante se encuentra a nivel 

del acetábulo original. 

Las clasificaciones de Crowe y Hartofilakidis 4 describe tres 

tipos de enfermedad congénita de la cadera del adulto. El primer 

tipo es la displasia en que la cabeza femoral está contenida 

dentro del acetábulo original. El segundo, consiste en 

una luxación baja, en que la cabeza femoral se articula con 

un falso acetábulo, cuyo borde inferior toca o sobrepasa el borde 

superior del verdadero acetábulo, dando la sensación de 

dos acetábulos superpuestos. El tercer tipo es la luxación 

alta, en que la cabeza femoral ha emigrado hacia arriba y atrás 

y no hay contacto entre el acetábulo verdadero y el falso. 

La principal indicación para implantar una ATC en pacientes 

jóvenes o de edad media es el aumento del dolor en coxartrosis 

secundarias con subluxación o luxación de la cadera. 

También pueden hacerse dolorosas caderas que han estado 

siempre en posición alta. 

El objetivo de cualquier ATC es eliminar el dolor, recuperar 

una marcha sin cojera y tener una función aceptable. Para 

alcanzarlos es necesario colocar el cotilo protésico en su 

lecho original para conseguir el centro de rotación en su nivel 

anatómico; reconstruir un mecanismo abductor que estabilice 

la pelvis; e igualar la longitud de los miembros inferiores. 

El componente femoral viene determinado por distintas circunstancias. 

Depende del nivel de resección que se pueda 

realizar y del acortamiento femoral necesario. Siguiendo la 

clasificación de Eftekhar, el estadio A, se pueden implantar 

componentes ordinarios normales. El grado B, la mayoría de 

las veces también, aunque suele ser útil disponer de vástagos 

con diferentes longitudes de calcar para compensar la resección 

femoral. En los casos en que falta todo el calcar o hay 

que resecar el fémur por debajo del trocánter menor como 

en los estadios C y D, el vástago debe ser recto. 

POSIBILIDADES TERAPÉUTICAS 

Los procedimientos quirúrgicos conservadores no están indicados 

cuando ha desaparecido la interlínea articular quedando 

entonces únicamente los procedimientos de sustitución 

articular. 

TÉCNICA QUIRÚRGICA 

La vía de acceso a la articulación de la cadera displásica 

más utilizada es la vía posterior, salvo en los casos de 

subluxación o deformidad tipo A de las descritas anteriormente, 

en que se puede acceder a la articulación por cualquier 

otra vía dependiendo de las preferencias del cirujano. Se 

aconseja una vía lo suficientemente amplia que permita ver 

sin dificultad ambos campos el acetabular y la extremidad 

proximal del fémur de forma circunferencial. 

Se debe identificar el nervio ciático y protegerlo. Si la luxación 

es unilateral donde existe una dismetría, se debe referenciar 

mediante dos puntos fijos, que será la medida de partida, 

para al final de la intervención, cuando se está comprobando 

la longitud del miembro, saber con bastante aproximación 

cuánto se ha alargado la extremidad. 

Para comprobar el estado del nervio algunos autores prefieren 

realizar la reducción de la prótesis con monitorización electromiográfica 

mediante potenciales evocados 5 . También se 

puede realizar una vez está reducida la prótesis definitiva, 

el test de despertar, utilizado en cirugía de corrección de la 

escoliosis, que es un método seguro de no haber lesionado 

por tracción excesiva el nervio ciático. 

Reconstrucción acetabular Implantar una prótesis de cadera 

en una deformidad tipo A no suele plantear ninguna 

dificultad añadida al implante en una coxartrosis severa. En 

muchas caderas subluxadas el acetábulo tiene el grosor 

suficiente para recibir, una vez fresado, un cotilo normal de 

bajo perfil. Lo que verdaderamente es importante es situarlo 

lo más cerca posible del centro de rotación de la cadera, 

aunque también está permitido colocarlo ligeramente alto 

con tal que esté medializado y no lateralizado. 

No siempre el cotilo implantado se encuentra completamente 

cubierto por hueso receptor. Si hace falta se puede recurrir 

a: a) realizar una osteotomía central, e introducir injertos de 

los últimos fresados acetabulares con el fin de medializar lo 

suficiente y conseguir una buena palanca abductora y evitar 

que el centro de rotación quede alto. 

Otra posibilidad (b) es realizar una acetabuloplastia atornillando 

un fragmento de la cabeza femoral resecada. Es la 

técnica más utilizada sobre todo por los cirujanos americanos 6 . 

Este aumento óseo trata de cubrir con hueso del propio 

paciente la falta de cobertura de la porción supero-lateral 

del acetábulo y que no suele sobrepasar el 20%. La tercera 

posibilidad (c) consiste en recubrir el cotilo con la técnica 

de Slooff 7 mediante una malla metálica atornillada a la 

hemipelvis, que contiene injertos troceados y compactados 

que reciben un cotilo cementado y presurizado. 

Reconstrucción femoral El tiempo femoral depende de la 

deformidad existente. Hay que realizar una resección para 

poder descenderlo hasta la situación del componente acetabular. 

La anteversión femoral exagerada que acompaña a 

la displasia se puede corregir durante el tiempo de fresado 

y preparación del conducto medular. Realizar una osteotomía 

desrotadora es complicado y debe reservarse para casos 

extremos, pero cuando está indicada es la única solución.



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Aparte de la anteversión femoral exagerada suele existir la 

mayoría de las veces una coxa valga y una estrechez del 

canal medular femoral. 

El vástago femoral puede ser normal si existe algo de calcar, 

o con cuello incorporado si la resección es más distal. Se 

utilizan indistintamente componentes cementados y no 

cementados. Entre los primeros existen series llamadas 

asiáticas ó displásicas que son de menor tamaño y con offset 

reducidos de 30,33,35 mm, y que precisamente están 

diseñadas para estos casos. También se pueden utilizar 

componentes no cementados ajustados a presión y modulares 

en su diseño, que permiten elegir el tamaño adecuado 

tanto en la porción metafisaria como en la diáfisis. Si además 

como caracterizan a este tipo de vástagos modulares la anteversión 

es independiente se puede elegir la necesaria de 

acuerdo a la anteversión con que se haya implantado el 

cotilo y evitar así una inestabilidad anterior. Si el trocánter 

mayor queda ascendido, se debe reinsertar más distal para 

obtener una buena palanca abductora y que no limite la abducción 

por interferencia contra la hemipelvis. 

En las deformidades tipo C y D, hay que realizar un acortamiento 

proximal del fémur con una transposición distal del 

trocánter mayor. Puede hacerse mediante una osteotomía 

transversa subtrocantérica 8 , en la que se reseca el fragmento 

femoral necesario, para que una vez liberadas las partes 

blandas y colocado el acetábulo en su posición, el vástago 

de prueba se pueda reducir sin excesiva tracción y sin que 

la prótesis quede demasiado tensa o la articulación en flexión. 

Hay tres formas de realizar dicha osteotomía subtrocantérica 

de acortamiento, que aunque en sí mismas tienen un gran 

parecido se realizan de forma un poco distinta y que se describen 

a continuación. 

1.- La técnica (arriba y abajo) exige una planificación meticulosa. 

Se coloca en primer lugar con la plantillas el cotilo 

previsto en su posición anatómica original. Se marca el 

centro de rotación de la cadera. Se señala el centro de la 

cabeza femoral protésica, calculando que el vástago quede 

ajustado y con el offset que le corresponde. La distancia 

entre el centro de la cabeza femoral protésica y el centro 

del verdadero acetábulo representa el máximo alargamiento 

que puede hacerse sin acortar el fémur. 

Una vez resecada la cabeza y cuello femorales, se inicia 

con las raspas la preparación del conducto medular con el 

fin de permitir la introducción del vástago de prueba. La 

osteotomía femoral se realiza a nivel del verdadero acetábulo, 

donde el fémur empieza a ser cilíndrico. El fragmento proximal 

de la osteotomía se separa hacia arriba y se mantiene en 

esta posición con uno o dos agujas de Kirschner para facilitar 

la exposición del acetábulo e implantación del cotilo protésico. 

A continuación se realiza la liberación de partes blandas 

necesarias, hasta que la cabeza de un vástago de prueba 

introducido en el conducto femoral pueda reducirse en el 

cotilo definitivo. El fragmento femoral distal a la osteotomía 

se coloca al lado del proximal y se reseca el segmento superpuesto. 

Se luxa la prótesis de prueba, reinsertando el vástago, 

que ahora mantiene ambos fragmentos intramedularmente, 

y se aprovecha para corregir la rotación. Se reduce de nuevo, 

y se puede implantar un vástago cementado o no. 

2) Otra posibilidad es la técnica puesta al día por Rorabeck 9 , 

que establece como contra-indicación para la cirugía cualquier 

historia reciente de artritis. Del mismo modo cualquier 

infección crónica debe tratarse previamente a la cirugía. 

Como en otras patologías entre ellas la desartrodesis, la 

falta de función de la musculatura abductora es un signo de 

mal pronóstico para el funcionamiento de la artroplastia 

Acceso a la articulación mediante incisión longitudinal lateral 

directa, porque de esta forma se puede acceder a la articulación 

por delante y por detrás. Debido a la anteversión 

la luxación de la cabeza femoral es más fácil por delante. 

Como muestran los dibujos de la técnica una vez resecada 

la cabeza femoral se empieza a preparar el fémur, teniendo 

cuidado de no excederse en el fresado ya que el fragmento 

distal femoral después de la osteotomía de resección puede 

quedarse ancho y no quedarse ajustada y firme esta parte 

del vástago femoral, por lo que es aconsejable realizar un 

fresado infradimensionado a lo previamente calculado. Con 

la osteotomía realizad y sin resecar se accede fácilmente 

al acetábulo, que se prepara como en cualquier otra técnica. 

Los problemas de cobertura se tratan como se ha descrito 

anteriormente. 

Una vez implantado el cotilo se coloca el vástago modular 

de prueba y se anota la resección a realizar. Una vez ajustado 

e insertado el vástago previsto se implementa la estabilidad 

a nivel de la osteotomía con una placa metálica atornillada. 

3) la tercera posibilidad es la ostetotomía de solapamiento 

de Paavilainen 10 que consiste en superponer en vez de resecar 

el fragmento subtrocantérico y reinsertar el fragmento 

proximal con el trocánter mayor incluido y la musculatura 

abductora lo más distal posible y se realiza osteosíntesis 

con dos tornillos. 

Se accede a la articulación por vía posterior y se talla una 

osteotomía a 7-9 cm de la punta del trocánter mayor. La 

parte proximal del vasto lateral se divide longitudinalmente 

y se libera la mitad posterior de la base del trocánter. Este 

fragmento proximal de 7-9 cm de fémur se divide longitudinalmente 

en dos partes. La parte interna se extirpa y se utilizará 

posteriormente como injerto para acetabuloplastia de techo 

de cotilo si es necesario. La parte externa comprende la inserción 

del glúteo medio y la mitad anterior del vasto lateral. 

La mejor forma para localizar el acetábulo es palpar el agujero 

obturador ya que justo por encima de él se encuentra 

la incisura que separa las dos superficies anterior y posterior 

del croissant articular. Normalmente se encuentra ocupado 

por grasa y tras el fresado con la fresa más pequeña es perfectamente 

reconocible. Una vez localizado se procede al 

fresado progresivo que permitirá implantar un cotilo de 40



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70 

mm de diámetro o mayor. Los problemas de cobertura 

acetabular son los mismos que con las otras técnicas. 

Una vez implantado el cotilo definitivo, se prepara el conducto 

femoral de forma habitual. Se introduce el vástago y se reduce 

con el tamaño de cabeza y longitud de cuello adecuados. 

El trocánter mayor con sus inserciones musculares 

se tensa hacia distal, lo suficiente para tener una buena potencia 

abductora. Se solidariza al fragmento distal con dos 

tornillos, uno anterior y otro posterior al vástago femoral. 

Esta reinserción distal del trocánter se debe hacer en 

abducción. Posteriormente se reinserta el vasto lateral al 

trocánter que se realiza plicándolo para darle la tensión adecuada. 

Con ésta técnica de solapamiento se puede conseguir 

alargar la extremidad entre 3-4 cm, pero es aconsejable 

controlar el estado del nervio ciático con potenciales evocados 

o con el test de despertar descritos con anterioridad. 

La serie personal estudiada consta de 29 pacientes; 25 en 

casos de cirugía primaria y 4 de cirugía de revisión, que 

fueron intervenidos desde junio 1999 hasta diciembre 2005. 

El 72% han sido mujeres y el 28% hombres. La principal indicación 

para la cirugía de implantación de ATC ha sido el 

dolor. La edad media de 48 años (rango entre 28 y 54) con 

un seguimiento entre 1 y 7 años. 

Los implantes utilizados en la presente serie han sido diversos 

ya que existen vástagos monobloques cementados y vástagos 

donde se puede elegir la longitud del cuello. La mayoría 

de los componentes acetabulares han sido no cementados. 

El componente femoral en los primeros casos de la serie ha 

sido el diseñado por Paavilainen pero al ser recto y solo 

disponer de superficie porosa en su porción metafisaria 

proximal no se adaptaba en todas las ocasiones al estado 

del hueso, por lo que en algunos casos se cementó la parte 

distal del mismo y en otros se utilizó en vástago displásico 

de Exeter cementado, con buen resultado. 

La intervención quirúrgica se realizó en decúbito lateral, siguiendo 

la descripción técnica de su autor. Entre las complicaciones, 

no se han presentado ni luxaciones, ni infecciones ni 

lesiones nerviosas. En 2 casos se produjo un fallo en la osteosíntesis 

que hubo que realizar cirugía con aporte óseo y 

nueva osteosíntesis. La longitud media ganada fue de 2.8 cms. 

Otra posibilidad es la implantación de un vástago a medida 

sin cementar, que requiere una planificación preoperatoria 

más rigurosa y que se consigue con TAC 3D con el que se 

consigue recuperar el centro de rotación de la cadera. Los 

resultados con un seguimiento de 10 años en pacientes 

menores de 50 años, muestran una curva de supervivencia 

de 96.1%, por lo que es una opción a tener en cuenta en 

pacientes jóvenes y, 

Existe otro procedimiento para poder implantar en su sitio 

original una artroplastia en una displasia alta de cadera y 

consiste en obtener mediante tracción esquelética o con 

fijadores externos durante un tiempo intermedio el espacio 

suficiente entre la extremidad proximal del fémur a la que 

se le ha resecado o no la cabeza y cuello femorales, y el 

cotilo original 11 . 

Para evitar complicaciones y fallos, en las ATC en pacientes 

con displasia se debe tener en cuenta: 1) la deformidad existente 

tanto en el acetábulo como en la extremidad proximal 

femoral; 2) el riesgo que puede sufrir el nervio ciático; y 3) 

no olvidar que se trata de pacientes jóvenes en los que es 

de suponer una expectativa para la artroplastia de larga 

duración. 

COMPLICACIONES 

Como en cualquier ATC que se realiza por otro motivo, se 

pueden presentar aflojamientos del componente acetabular 

y femoral sobre todo cuando se ha utilizado un modelo liso 

y que favorecía poco la osteointegración. Con la mejoría de 

las superficies de recubrimiento y la posibilidad de mejorar 

la estabilidad primaria, los aflojamientos han disminuido. 

El desgaste excéntrico del polietileno y la osteolisis periprotésica 

continúan siendo una de las complicaciones que obliga 

a la cirugía de revisión, ya que se trata de acetábulos pequeños 

y necesariamente aunque la cabeza sea de 22 mm 

el grosor del inserto nunca es excesivo. Los fracasos en la 

consolidación de cualquier tipo de osteotomía es otra posibilidad 

de indicación de la cirugía de revisión. Las lesiones 

del ciático son complicaciones frecuentes en este tipo de 

cirugías. 

CONCLUSIONES 

1. En primer lugar se debe tener en cuenta que se trata de 

pacientes jóvenes y con demandas cuya esperanza de 

vida es larga. 

2. Las deformidades anatómicas se encuentran en ambas 

superficies articulares, acetábulo y extremidad proximal 

del fémur y se deben conocer perfectamente para implantar 

ambos componentes en la posición adecuada para el 

correcto funcionamiento de la artroplastia. 

3. En los casos unilaterales, la dismetría es importante y es 

necesario realizar cualquier tipo de osteotomía subtrocantérica 

de acortamiento. 

4. El nervio ciático, con sus disfunciones completa o parcial 

es una de las complicaciones más frecuentes y obliga a 

no alargar el miembro más de 2.5 ó 3 centímetros. 

BIBLIOGRAFÍA 

1. Millar NH, Krishnan SG, Kamaric E, Noble PC: Long-term 

results of the dial osteotomy in the treatment of high-grade 

acetabular dysplasia. Clin Orthop Relat Res 2005;433:115- 

23. 

2. Picault C: Devenir à long terme de la dysplasie de hanche 

après traitement orthopédique ou chirurgical. Cahiers 

d’enseignement de la SOFCOT. Conferènces d’enseignement 

1999:57-86.



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3. Harris WH, Crothers O, Oh I: Total hip replacement and 

femoral head bone grafting for severe acetabular 

deficiency in adults. J.Bone Joint Surg 1977;59-A:752- 

5. 

4. Hartofilakidis G, Stamos K, Karachalios T, Ioannidis TT, 

Zacharakis N: Congenital hip disease in adults: Classification 

of acetabular deficiencias and operative 

treatment with acetabuloplasty combined with total hip 

arthroplasty. J.Bone Joint Surg 1996;78:683-692. 

5. Paavilainen T: Total hip replacement for developmental 

dysplasia of the hip. Acta Orthop Scand 1997;68:77-84. 

6. Cabanela ME: Total Hip Arthroplasty: Degenerative 

Dysplasia of the Hip. In: Advanced Reconstruction Hip. 

Ed: Lieberman J, Berry D. AAOS. 2005:115-20. 

7. Slooff TJJH, Huiskes R, van Horn J, Lemmens AJ.: Bone 

grafting in total hip replacement for acetabular protrusion. 

Acta Orthop Scand 1984;55:593-6. 

8. Yasgur D, Stuchin S, Adler E, DiCesare P.: Subtrochanteric 

Femoral Shortening Osteotomy in Total Hip 

Arthroplasty for High-riding Developmental Dislocation 

of the Hip. J. Arthroplasty 1997;12:880-7. 

9. Rorabeck C, Burnet SJ: Total Hip Arthroplasty: High Hip 

Dislocation. In: Advanced Reconstruction Hip. Ed: Lieberman 

J, Berry D. AAOS. 2005:121-9. 

10. lkka Helenius, Ville Remes, Kaj Tallroth, Jari Peltonen, 

Mikko Poussa, and Timo Paavilainen 

Total Hip Arthroplasty in Diastrophic Dysplasia 

J. Bone Joint Surg. Am., Mar 2003;85:441-447. 

32. Caveiro N: Experiencia personal con la ATC en DDH. 

Libro de resúmenes. SPOT Vilamoura 2007 

HIP RESURFACING ARTHROPLASTY IN 

DYSPLASTIC HIPS 

Michael Menge 



BACKGROUND 

The long term prognosis of total hip replacement (THR) is 

poor in younger patients. Therefore bone sparing techniques 

as resurfacing of the femoral head have become very popular 

in Germany. As patients with congenital dysplasia of the hip 

(CDH) very often develop early osteoarthrosis there might 

be the possibility to use this procedure in anatomically difficult 

cases. The purpose of this study was to evaluate the possibilities 

and the problems in resurfacing dysplastic hips. 

METHOD 

Between 1999 and 2006 more than 1.500 patients received 

a MoM resurfacing of the hip, from which 91 patients (6%) 

suffered from severe secondary osteoarthrosis after mild or 

severe CDH. The rate of dysplastic hips in our total hip replacement 

(THR) group was less because the high number 

of degenerative coxarthrosis of the elderly: 177 out of 6875 

cases (2.6%). The mean age from our CDH patients was 

47.7 years (30.7 – 64.9). In most cases the posterior approach 

was used, only two surgeons of our staff preferred the lateral 

approach. 

RESULTS 

In most cases the resurfacing of the head was not the 

problem but the fixation of the acetabular socket in a shallow 

acetabulum with bone defects mostly at the anterior rim. Two 

devices worked fairly well in these circumstances: The BHR 

and the Icon dysplasia cup with additional fixation screws 

from the upper rim. We additionally tried the ESKA Bionik 

system offering a modular socket allowing screw fixation of 

the outer shell then covered by a metallic liner. In dysplatic 

acetabula the missing macro- and microstructure at the central 

back of the ESKA sockets let to a higher revision rate. 

Typical cases and problems will be demonstrated. 

CONCLUSIONS 

Our 9-year experiences with MoM resurfacing procedures in 

young patients with osteoarthrosis are excellent. In CDH the 

resurfacing procedure may be extremely difficult and there 

were more complications, especially loosening of the socket 

or femoral nerve palsies due to the missing ventral wall of 

the acetabulum. There was a revision rate of 10% in the cases 

with severe dysplastic acetabula. In the majority the patients 

will profit from good function and in the future in case 

of revision from preserved bone stock at the femoral side. 

CHARNLEY LOW-FRICTIONAL 

TORQUE ARTHROPLASTY. FOLLOW-UP 

TO 38 YEARS. 

PROBLEMS AND SOLUTIONS 

B. M. Wroblewski, P. D. Siney, P. A. Fleming 



We studied survivorship after Charnley low-frictional torque 

arthroplasty with revision as the end point. 

Between November 1962 and June 2005, 22,066 primary 

operations had been carried out at Wrightington Hospital by 

over 330 surgeons. By June 2006, 1001 (4.5%) hips had been 

revised. 

Survivorship analysis at 38 years with revision as the end 

point was: Infection 95%, dislocation 98%, fractured stem 

88.6%, loose stem 72.5% and loose cup 53,7%.



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Deep infection is an early problem that is tackled early with 

one stage revision favoured. 

The very low incidence of revisions (0.3%) in our study together 

with other studies reporting similar low rates of revision 

for dislocation using a small femoral head clearly shows the 

common belief that the small head of the Charnley LFA carries 

a high risk of dislocation - is unfounded. 

Fracture of the original “flat back” stem was, at one stage, the 

most common indication for a revision. Introduction of high 

nitrogen content stainless steel stem as well as the improved 

cementing technique has eliminated the problem. 

Early stem revisions within 5 years can be attributed to the 

less than optimal surgical technique. Endosteal cavitation of 

the femur and resultant stem loosening did not appear to become 

a problem until after 11 years, when the incidence of 

stem fracture has passed its peak. It is suggested that the 

mechanism -lack or loss of proximal support- is similar to both. 

The late problem being proximal strain shielding of the femur. 

Wear and loosening of the ultra high molecular weight polyethylene 

cup is the main long term problem. 

Since clinical results do not reflect the mechanical state of the 

arthroplasty, to await symptoms would invariably mean that 

revisions are likely to be carried out late, and thus, the incidence 

and the complexity of complications are likely to increase. 

Our principle of regular follow-up and early revisions, if need 

be for radiographic changes alone, is an integral part of the 

informed consent for the operation. 

Our conclusion is that regular follow-up after hip replacement 

is essential. The frequency, judged from the revision patterns, 

would suggest that every two years would not be unreasonable. 

Recording of all operative findings at revision is essential. 

PREVENTION AND TREATMENT OF 

RECURRENT DISLOCATION IN HIP 

ARTHROPLASTY 

Rudolph Geesink MD PhD 


Netherlands 

Despite all progress in fixation of implants, recurrent dislocation 

may prove to be a persistent problem with significant morbidity 

for patients and causes for litigation for surgeons. It may complicate 

1-5% of primary arthroplasties and even more in revi- 

sion cases or specific patient populations. Causes are complex 

and multi-factorial and may be related to patient, implant or 

surgeon. 

PATIENT FACTORS 

- high age 

- female gender 

- dysplasia of the hip 

- hip fracture patients 

- obesity 

- previous surgery of the hip including hip revision arthroplasty 

- soft tissue factors including poor neuromuscular status 

- poor patient compliance (alcohol and other medications) 

IMPLANT FACTORS 

- geometry of femoral neck (configuration, correction of 

length & offset) 

- head size & head-neck ratio 

- modularity of components 

- stem &cup design issues 

SURGICAL FACTORS 

- preoperative planning 

- surgical approach 

- exposure & releases 

- component positioning and role of navigation 

- surgeon experience 

Factors that are within control of the surgeon to improve his 

results regarding stability of components will be discussed. 

These may include: 

- preoperative planning for choice of right component 

- importance of restoring adequate length and offset for 

soft tissue tension 

- importance of optimal range of motion to avoid impingement 

and subluxation 

- the ‘rule of forty’ regarding implant positioning 

- use of larger femoral heads made possible by improved 

poly-ethylenes, ceramic-ceramic or metal-metal bearing 

couples. 

- avoidance of lipped liners or skirted femoral heads that 

reduce range of motion 

- retention cups should only be used if other factors have 

been rules out and soft tissue stability is the main culprit 

of the stability problem. 

Some algorithms based on previous factors will be discussed 

in the presentation.



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ADVANTAGES OF THE USE OF 

MODULAR NECKS 

J. David Blaha 

Ann Arbor. Michigan, (USA) 

The modular neck offers advantages in fixation, function and 

stability of the reconstructed hip. 

Stability of the hip is usually thought of only with regard to hip 

dislocation. However, stability during function requires that 

the reconstruction place components in as near a normal 

position as possible. As the art and science of total hip replacement 

has progressed the operation has been offered to 

younger patients and to patients who, although older, expect 

nearly normal function. It is reasonable to assume that restoring 

the lever arms of the musculature about the hip will lead 

to the most normal stability and function for that joint. There 

has been a considerable interest in recent years in “restoring 

the offset” for total hip replacements with comments usually 

made concerning abductor strength and dislocation. Such 

restoration of offset should be considered in three-dimensions 

and is the key to improved function in total hip replacement. 

The position of the center of the femoral head relative to the 

remainder of the femur determines the lever arms of the 

muscles about the hip as well as the limb length contributed 

by the femur. Relative to the proximal shaft of the femur the 

center of the femoral head is proximal, medial and slightly 

anterior although there is considerable variation between 

individuals in this relative position. 

The shape and size of the femoral canal is also quite variable 

between individuals. Because of this fact it is not always 

possible to obtain the ideal press-fit for a cementless total hip 

femoral component in the canal while simultaneously restoring 

the center of the femoral head to the ideal position relative to 

the canal so that the lever arms for the muscles are restored. 

Often the surgeon must “optimize” the situation by accepting 

either less-than-ideal femoral head position or less-than-ideal 

interference fit in the femoral canal. 

A modular neck for the femoral component of total hip arthroplasty 

helps to solve this problem. The femoral canal is prepared 

so that the component gets the best press-fit. The 

modular neck then allows adjustment of the limb length, offset 

and version through a variety of necks that connect to the 

femoral component with a taper-lock junction. This type of modular 

femoral neck has been in use for 16 years. The design 

allows adjustment of the position of the femoral head relative 

to the femoral component and, through a series of trial components, 

allows the surgeon to test the limb length and stability 

at the operating table. For the patient, the properly restored 

hip center leads to the best possible function. 

REFERENCES 

1. Antonietti B, Pademi S, Sama D, Comitini V, Sudanese 

A: Anatomic cementless total hip arthroplasty with ceramic 

bearings and modular necks: 3 to 5 years follow-up. Chir 

Organi Mov. 2003 Jul-Sep:88(3):259-65. 

2. Baleani M, Viceconti M Wilchholz K Toni A: Metallic wear 

debris in dual modular hip arthroplasty. Chir Organi Mov. 

1997 Jul-Sep:82(3):231-8. 

3. Blaha JD: The modular neck: Keystone to Functional Restoration. 

Orthopedics. 2006 Sep;29(9):804-5 

4. Fessy MH, Bejui J, Fischer LP, Bouchet A: The upper end 

of the femur: dimensions of the endosteal canal. Surg Radiol 

Anat. 1995;17(2):155-60, 21-3. 

5. Kaneuji A, Matsumoto T, Nishino M, Miura T, Sugimori T, 

Tomita K: Three –dimensional morphological analysis of 

the proximal femoral canal, using computer-aided design 

system in Japanese patients with osteoarthrosis of the hip. 

J Orthop Sci. 2000;5(4):361-8. 

6. Rubin PJ, Leyvraz PF, Aubaniac JM, Argenson JN, Esteve 

P, de Rogiuin B.: The morphology of the proximal femur. 

A three-dimensional radiographic analysis. J Bone Joint 

Surg Br. 1992 Jan;74(1):28-32. 

7. Toni A, Sudanese A, Pademi S, Guerra E, Bianchi G, Antoniette 

B: Cementless hip arthroplasty with a modular 

neck. Chir Organi Mov. 2001 Apr-Jun:86(2):73-85. 

8. Vicecont iM, Baleani M, Squarzoni S Toni A: Fretting wear 

in a modular neck hip prosthesis. J Biomed Mater Res 

1997 May:35(2):207-16. 

9. Viceconti M, Ruggeri O, Toni A, Giunti A: Design-related 

fretting wear in a modular neck hip prosthesis. J Biomed 

Mater Res. 1996 Feb:30(2):181-6.#12 - THURSDAY, 

DECEMBER 14, 2006 - SESSION III 

CÚPULA DE DOBLE MOVILIDAD 

José Palacios 

Clínica La Zarzuela, Madrid (España) 

Dadas las circunstancias de discusión que constantemente 

existen en nuestra especialidad con los pares de fricción, 

según las características de los materiales que lo integran 

(cerámica-polietileno, metal-polietileno, metal-metal, cerámicacerámica), 

pocas veces se ha tenido en cuenta que existe 

la posibilidad de utilizar, en la misma prótesis, no uno sino 

dos pares de fricción. 

En la ponencia defendemos esta posibilidad con pares de 

fricción entre el cotilo metálico con fijación, sin o con cemento, 

inserto de polietileno sobre el cotilo metálico y cabeza preferentemente 

cerámica, aunque también metálica. De esta 

forma existirá un primer par de fricción entre el inserto de 

polietileno (sandwich) y la superficie pulida del cotilo metálico, 

y un segundo par de fricción entre la cabeza femoral protésica, 

que podría ser de 22 ó 28 mm, y el inserto de polietileno. 

De esta forma se repartirán las solicitaciones de fricción entre 

ambas superficies, la usura será menor y la posibilidad 

de movimiento mayor que además, dado el diseño, tanto del 

cotilo como del inserto, la hacen dificilísimamente luxable. 

Se hace la discusión oportuna sobre este tipo de prótesis.



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RAPID RECOVERY THR: PAIN, 

ANESTHESIA, PAIN MANAGEMENT, AND 

SAME DAY DISCHARGE 

Aditya Vikram Maheshwari, M.D., Myriam Boutary, BS, 

Andrew G. Yun, M.D., Leigh Ellen Sirianni, OPAC, and 


Medical Director Arthritis Institute Centinela Hospital, 


Methods for managing pain after a total hip replacement 

have changed substantially in the past 5 years. We documented 

the outcome of patients treated with a multimodal 

pain program designed to avoid parenteral narcotics. Avoidance 

of parenteral narcotics can essentially eliminate the 

complications of respiratory depression, ileus, and narcotic 

induced hypotension. It can minimize nausea and vomiting 

which cause dissatisfaction with an operation. Twenty-one 

of 140 patients (15%) needed parenteral narcotics postoperatively 

with only nine patients (6.4%) using parenteral 

narcotics after the day of surgery. Mean pain scores were 

below 3 of 10 on all postoperative days. There were no patients 

with respiratory depression or ileus, and four (2.9%) 

with urinary retention. Nausea occurred with 35 patients (25%) 

in the recovery room and in 28 patients (20%) thereafter. 

Emesis occurred in five patients (3.6%) with two incidences 

in the recovery room. One hundred and thirty-eight patients 

(98.6%) were discharged home at a mean of 2.7 seven days 

postoperatively with 98 (70%) on a single assistive device. 

The multimodal pain management program, which avoided 

parenteral narcotics, was effective in providing pain relief, 

nearly eliminating emesis, and eliminating the severe complications 

of respiratory depression, urinary tract infection and 

ileus, as well as accelerating function. 

Appendix. Medications for Multimodal Pain Program for Total 

Hip Replacement 

Note: Patients do NOT need to stop Celebrex before surgery 

Preoperative (morning of surgery) 

1. OxyContin, 10 mg PO 

2. Celebrex, 400 mg PO (if allergic to sulpha, then no NSAIDs) 

3. Tylenol, 500 mg PO 

4. Prevacid, 30 mg, PO 

5. If allergic to sulpha drugs, Limbrel, 1000 mg 

Recovery room 

1. For bilateral hips, keep epidural catheter capped until 

transferred to floor 

2. For primary hips, pull epidural catheter in operating room 

3. ASA, 600 mg per rectum 

4. Toradol, 30 mg IV x 1 dose as needed for mild to moderate 

pain (15 mg IV if older than 65 years) 

5. OxyIR, 5 mg PO as needed for severe pain 

6. Ice applied to operated hip 

Floor program 

1. If younger than 65 years, Norco, 10 mg, 1 tab PO, alternating 

with Tylenol ES, 500 mg PO every 4 hours from 6 

PM to 6 AM x 2 days 

2. If older than 65 years, Darvon, 65 mg, 1 tab PO, alternating 

with Tylenol ES, 500 mg PO every 4 hours from 6 PM to 

6 AM x 2 days 

3. Celebrex, 200 mg PO twice daily, starting postoperative 

day 1, or Lembril, 500 mg PO twice daily 

4. Vicodin, 5mg/500mg, 1-2 tab PO every 3-4 hours as needed 

for pain 

5. Norco, 10mg/325mg, 1-2 tab PO every 3-4 hours as needed 

for pain 

6. Darvocet N-100, 1 tab PO every 4 hours as needed for 

pain (if older than 65 years) 

7. Ultram, 50 mg, 1 tab. PO every 4-6 hrs as needed for 

pain 

8. Ancef (cefazolin), 1 gm IVPB every 8 hours x 24 hours 

9. Anzemet, 12.5 mg IV every 6 hours x 24 hours 

10. If reflux disease, Zofran, 4 mg IV every 6 hours x 24 

hours (instead of Anzemet) 

11. Reglan, 10 mg IV, IVP every 8 hours x 48 hours 

12. Enteric coated acetylsalicylic acid (ECASA), 325 mg 1 

tab PO twice daily 

13. Milk Of Magnesia 30 ml every 8 hours 

14. Colace, 100 mg PO twice daily 

15. Dulcolax suppository per rectum daily as needed for 

constipation 

16. Prevacid, 30 mg PO twice daily 

17. Dietary for food preferences 

18. Regular diet 

19. Cream of wheat for breakfast daily to avoid need for iron 

tablets 

Discharge 

1. Celebrex, 200 mg PO twice daily x 21 days (total of 3 

weeks) or Lembril, 500 mg PO twice daily 

2. ECASA, 325 mg 1 tab PO twice daily (for 30 days after 

surgery) 

3. Prevacid, 30 mg twice daily (while on ECASA) 

Pain medications (whatever patient was on while in hospital)



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DIAGNOSIS OF THE PAINFUL 

CEMENTLESS HIP 



Netherlands 

If the goals of arthroplasty to restore longevity of pain-free 

function are not met, the patient may visit the surgeon for 

further diagnosis and selection of treatment. Many factors 

may be responsible for problems in arthroplasty and radiology 

is an important diagnostic instrument. However with cementless 

arthroplasty radiological failure criteria are much more 

difficult to define compared to cemented arthroplasty. This 

is mainly caused by the great variety in fixation principles 

and design factors of cementless hip implants. 

- material (stiffness, titanium or CoChr alloys) 

- design (cylindrical 2-D 3-D wedge) 

- surface texture (macro-texture, porous-or fiber-mesh 

coating) 

- biological coating (HA-coating of variable length) 

In addition there are multiple failure mechanisms for implants: 

- fracture, device or bone 

- disturbed biomechanics 

- loosening 

- infection 

- wear & lysis 

- stress-shielding 

- pain without any of previous problems 

Radiological diagnostic tools may include: 

- standard X-rays, protocol & lateral for position and gross 

fixation 

- interface study using contrast or nuclear arthrography 

- technetium, gallium or indium scintigraphy to rule out 

in-fection 

- CT-scan to detect hidden osteolysis (modern metal removal 

software) 

- fluoroscopy rarely necessary 

Through systematic use of radiological tools, proper interpretation 

of clinical signs plus knowledge of potential failure mechanisms 

it is usually possible to arrive at a diagnosis and 

prove or disprove one of the previous failure mechanisms. 

Points to remember: 

- interpret clinical signs 

- know the implant characteristics 

- be aware of potential problems 

- choose correct diagnostic tools 

- interpret radiographic signs 

- check for infection 

- diagnosis usually possible preoperatively 

THE INCIDENCE OF THIGH PAIN AND 

CLINICAL OUTCOME OF A TAPERED 

FEMORAL STEM 

Victor M. Goldberg, M.D; Sam Akhavan, M.D. 



Tapered femoral components were designed to provide a 

cementless alternative in patients with narrow femoral canals. 

Major concerns with this stem include perioperative fracture 

and thigh pain. To ascertain the frequency of these concerns, 

we retrospectively reviewed 100 consecutive hips in 97 patients 

with osteoarthritis who underwent total hip arthroplasty with 

a tapered fibermetal femoral component. Patients were evaluated 

postoperatively using Harris Hip Scores and sequential 

radiographs. The average age of the patients was 56.5 years 

(range 33.7-73.5 yrs). Minimum followup was 6 years (average 

6-10 yrs). One patient died at 1.3 years and was excluded 

from the study. Four patients had incomplete perioperative 

fractures of the calcar without extension below the lesser trochanter. 

All fractures were recognized perioperatively and 

fixed with cerclage wires without further problems. Four patient 

underwent revision surgery, two for recurrent dislocation secondary 

to malpositioning of the acetabular cup, one for a 

greater trochanteric fracture after a fall, and one for a fractured 

zirconium femoral head. At last followup, the mean Harris Hip 

Score was 98 (Range 86-100); two patients had mild anterior 

thigh pain. All femoral stems appeared to have bony integration 

radiographically. Tapered femoral stems provide a cementless 

alternative in patients with a narrow femoral canal without 

undue risk of perioperative fracture of thigh pain. 

LEG LENGTH INEQUALITY: 

PREVENTION AND MANAGEMENT 

Douglas A. Dennis, MD 

Adjunct Professor, Department of Biomedical Engineering 

University of Tennessee, Assistant Clinical Professor, 

University of Colorado Health Sciences Center, Clinical 

Director, Rocky Mountain Musculoskeletal Research 

Laboratory 

Denver, Colorado (USA) 

Leg length discrepancy (LLD) is an undesired complication 

of total hip arthroplasty (THA). It creates numerous potential 

adverse effects including low back pain, sciatica, limp, hip 

instability, increased hip forces, hip pain (in non-implanted



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hips), and patient dissatisfaction resulting in litigation. The 

incidence of LLD varies from 16-96%. A long leg is more 

common, more perceived by the patient, and statistically 

correlated with reduced hip function scores. Patient perception 

of a leg length inequality often correlates poorly with true 

radiographic leg length measurements. Patients at risk for 

a symptomatic leg length discrepancy include those with 

short stature, coxa vara, acetabulae protrusio, preoperative 

pelvic obliquity, and preoperative flexion contracture. 

Preoperative LLD can occur due to distorted hip anatomy or 

false discrepancy due to pelvic obliquity associated with hip 

soft tissue contractures or lumbar scoliosis. Post-operative 

LLD is most commonly due to intraoperative technical errors 

including errors in neck resection, failure to duplicate the 

anatomic hip center, accurate choice of prosthetic neck length, 

or failure to duplicate femoral offset requiring increased vertical 

length to gain hip stability. 

Prevention of LLD requires preoperative planning and accurate 

intraoperative execution of the preoperative plan. Preoperatively, 

true leg length discrepancies can be determined by 

tape measurement (anterior-superior iliac spine to medial 

malleolus), floor blocks, and assessment of the level of the 

iliac crests. Various radiographic measurements are available 

typically using a combination of landmarks including the 

trans-ischial line, inter-teardrop line, femoral head center, 

and the greater and lesser trochanters. Additional, more 

precise radiographic leg length assessment options include 

orthoroentgenograms and CT scanning. Templating of preoperative 

radiographs is critical to determine intraoperative 

decisions, such as the level of the femoral neck resection, 

choice of prosthetic neck length and offset, and positioning 

of the acetabular component. Multiple intraoperative techniques 

are available to assist in accurate leg length determination. 

Many utilize measurements from fixed landmarks proximal 

and distal to the hip joint. These measurements are initially 

obtained before the hip is dislocated and repeated after trial 

components are inserted to determine intraoperative leg 

length changes. An intraoperative radiograph can be obtained 

to assure that precise execution of the preoperative plan has 

obtained. 

Treatment of LLD is based on etiology and patient disability. 

Many discrepancies are not perceived by the patient and can 

be ignored. Others can be managed with utilization of heel 

lifts. Operative treatment options include manipulation of modular 

femoral and acetabular components, component revision 

in cases of major component malposition, and greater trochanteric 

advancement in cases requiring substantial component 

shortening. 

BIBLIOGRAPHY 

1. Bose WJ: Accurate limb-length equalization during total 

hip arthroplasty. Orthopedics 23(5): 433-6, 2000. 

2. Edeen J, Sharkey PF, Alexander AH: Clinical significance 

of leg-length inequality after total hip arthroplasty. Am J 

Orthop 24(4): 347-51, 1995. 

3. Goodman SB, Huene DS, Imrie S: Preoperative templating 

for the equalization of leg lengths in total hip arthroplasty. 

Contemp Orthop 24(6): 703-10, 1992. 

4. Jasty M, Webster W, Harris W: Management of limb length 

inequality during total hip replacement. Clin Orthop Relat 

Res 333: 165-71, 1996. 

5. Konyves A, Bannister GC: The importance of leg length 

discrepancy after total hip arthroplasty. J Bone Joint Surg 

Br 87 (2): 155-7, 2005. 

6. Maloney WJ, Keeney JA: Leg Length discrepancy after 

total hip arthroplasty. J Arthroplasty 19(4 Suppl 1): 108- 

10, 2004. 

7. Parvizi J, Sharkey PF, Bissett GA, Rothman RH, Hozack 

WJ: Surgical treatment of limb-length discrepancy following 

total hip arthroplasty. J Bone Joint Surg Am 85-A(12): 

2310-7, 2003. 

8. Ranawat CS: The pants too short, the leg too long! Orthopedics 

22(9): 845-6, 1999. 

9. Ranawat CS, Rao RR, Rodriguez JA, Bhende HS: Correction 

of limb-length inequality during total hip arthroplasty. 

J Arthroplasty 16(6): 715-20, 2001. 

10. Ranawat CS, Rodriguez JA: Functional leg-length inequality 

following total hip arthroplasty. J Arthroplasty 

12(4): 359-64, 1997. 

11. Rosler J, Perka C: The effect of anatomical positional relationships 

on kinetic parameters after total hip replacement. 

Int Orthop 24(1): 23-7, 2000. 

12. Shiramizu K, Naito M, Shitama T, Nakamura Y, Shitama 

H: L-shaped caliper for limb length measurement during 

total hip arthroplasty. J Bone Joint Surg Br 86(7): 996- 

9, 2004. 

13. Suh KT, Cheon SJ, Kim DW: Comparison of preoperative 

templating with postoperative assessment in cementless 

total hip arthroplasty. Acta Orthop Scand 75(1): 40-4, 

2004. 

14. White TO, Dougall TW: Arthroplasty of the hip. Leg length 

is not important. J Bone Joint Surg Br 84(3): 335-8, 2002. 

15. Woolson ST, Hartford JM, Sawyer A: Results of a method 

of leg-length equalization for patients undergoing primary 

total hip replacement. J Arthroplasty 14(2): 159-64, 1999.



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84 

15.15 - 18.30 h 

CADERA / HIP 

Cadera de revisión / Hip revision 

Moderador: Antonio Coscujuela 

SURGICAL TECHNIQUES IN REVISION 

HIP ARTHROPLASTY 

Peter McLardy-Smith and the Oxford Hip & Knee Group 

Nuffielsd Orthopaedic Centre, 

Oxford (Great Britian) 

Revision hip arthroplasty is an increasingly important problem 

with numbers and technical difficulty increasing. One of the 

major challenges is bone loss and successful outcome is inversely 

related to the extent of bone deficiency. 

In the femur weakened or absent bone can be by passed 

by devices which rely on distal fixation in the diaphysis, but 

this will lead to proximal stress shielding and further weakening 

of remaining proximal femoral bone. Impaction allografting 

is an established technique aiming to reconstitute the proximal 

femoral bone by cementing a polished tapered wedge in to 

the graft construct. This paper describes the use of a specific 

modular device (the Oxford Universal Hip) in which the metaphyseal 

portion slides over the diaphyseal stem, but is not 

fixed to its surface so that it is free to sink or rotate on the 

stem. The stem can therefore by bypass distal defects and 

the bone impaction is needed only in the metaphyseal portion, 

where the load transfer occurs. 

Using this technique we have studied 173 hips, in which 

there were severe metaphyseal defects (Paprosky Grade 

3A or worse). Using the Oxford Hip Score there was a highly 

significant improvement in score post operatively and the 

worst case survivorship is 93%. A mean of only 1.8 femoral 

heads were required for the impaction grafting. Post operative 

fractures at the tip of the previous failed prosthesis are 

eliminated by the long stem and because the polished wedge 

was cemented into the graft construct, local antibiotics 

delivery is enabled from the cement. 

CEMENT-IN-CEMENT REVISION 

-DECREASING THE MORBIDITY OF 

REVISION SURGERY 




IMPACTED BONE GRAFT 

IN FEMORAL REVISION 

Aaron G. Rosenberg MD 

Professor of Orthopaedic Surgery Rush Medical College 


The revision technique of of impacting allograft bone chips 

into the proximal femoral canal and then using cement to fix 

the stem in the newly “created” allograft neo-endosteal canal 

allows for better cement fixation at the endosteal surface by 

improving the quality of the bone present for cement interdigitation 

while allowing for bone stock restoration to the 

upper end of the femur. This is a particularly appropriate 

technique in the patient who has substantially compromised 

endosteal bone stock or substantial endosteal expansion 

(the so called patulous proximal femur). This technique may 

also be helpful when used above long distal cement columns 

that may be difficult to remove and can be used to support 

the bone packing above. The procedure is technique dependent, 

requires appropriate equipment and should be used 

after appropriate training. 

Several centers have reported intermediate-term results, 

most often using stems of a similar geometry: a double-



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86 

tapered, highly polished, non-collared device. Advocates of 

these devices state that subsidence does not automatically 

lead to clinical loosening because the stem’s so-called “selftightening 

geometry” allows re-stabilization within the cement 

mantle as subsidence occurs. Subsidence of the wedgeshaped 

stem may also provide a beneficial compressive load 

to the bone graft. However, other authors have raised concerns 

about the supposed benign nature of stem subsidence, and 

impaction allografting has been succesfully performed using 

stems that resist subsidence, including those with a rough 

surface finish and precoating. 

Impaction allografting is one of the more technically demanding 

types of femoral reconstruction, and the frequency of complications 

in reported series reflects this. Dislocation rates typically 

range from 3-6 percent, and infection rates are similar; 

most re-operations have been performed for periprosthetic 

fracture management, though hardware-related trochanteric 

bursitis and recurrent dislocation also have required surgery. 

However, the incidence of greater trochanteric osteotomy nonunion 

seems high with impaction grafting, ranging from 33- 

50%. This may be related to compromised proximal bone stock 

or the presence of cement interposed in the osteotomy site. 

Femoral fracture and perforation of the cortex were amongst 

the most common and potentially destructive complications 

in early reports; the incidence ranging from 5-24 % with 

higher rates in series that selected patients for impaction 

grafting based on femoral bone-stock deficiency. Intra-operative 

fracture usually occurs during the vigorous impaction 

process required to obtain a stable neo-endosteum; re-inforcement 

of the cortical shell, either with cortical strut grafting 

or synthetic mesh should be performed if the integrity of the 

cortex is in question. Intra-operative perforation of the femoral 

shaft typically occurs during cement removal, and if recognized, 

is easily treated with cortical strut allografts. Postoperative 

fracture of the femur may occur about the stem tip 

or more proximally; it may be related to unrecognized femoral 

perforation, non-displaced fracture at surgery, or unappreciated 

areas of osteolysis. The use of longer implants to bypass 

such defects has been strongly recommended. 

Recent reports on longer term follow up are now available 

and encouraging. In the JBJS (2006) Sloof and colleagues 

reported on 33 consecutive cases at a mean of 10.4 years. 

There was one unrecognized intraoperative fracture, which 

healed following nonoperative treatment. There were three 

postoperative femoral fractures, all through cortical defects 

at the level of the tip of the prostheses. All fractures healed 

after plate fixation, and all femoral implants were left in situ. 

No re-revisions were required. The average subsidence of 

the stem within the cement mantle was 3 mm; seven stems 

migrated 5 mm. The average Harris hip score improved to 

85 points (68 -100) with a survival rate of 100%. 

In the 2006 Journal of Arthroplasty Capello reported on 48 

impaction graftings revision using a bead-blasted chrome 

cobalt stem with minimum 6 1/2-year follow-up. There were 

only 2 failures due to aseptic loosening of the femoral component 

(4%). But a total of 22 total complications with overall 

failure rate of 21% was noted. 

A Scandinavian series (Acta Ortho 2006) reviewing only the 

most severe bone deficiency cases (21 hips Endo-Klinik 

classification grade III or IV with 4 having a preoperative 

fracture). No femoral re-revisions had been necessary after 

a mean follow-up of 60 (41-85) months. The mean Harris 

Hip Score improved by 39 points to 78 points. 2 fractures 

occurred postoperatively, 1 of which needed reoperation with 

osteosynthesis. 1 patient needed a closed reduction after 

dislocation. 4 stems showed significant subsidence (> 10 

mm) in the follow-up radiographs. 

The 2003 series reported in the JBJS by Ling’s group reported 

on all patients from one centre who had undergone surgery 

more than five years previously. This included 207 patients 

with 226 hips operated on by 32 different surgeons. 33 

patients (35 functioning hip)s died and 1 was lost to followup. 

Two (1%) developed early postoperative infection. 12 

stems underwent a further surgical procedure for aseptic 

failure, ten were for femoral fracture and two for loosening. 

Survivorship with any further femoral operation as the endpoint 

was 90.5% (confidence intervals, 82 to 98) and using 

femoral reoperation for symptomatic aseptic loosening as 

the endpoint, the survivorship was 99.1% (confidence intervals, 

96 to 100) at 10 to 11 years. 

An important limitation to consider when comparing clinical 

reports on this technique is the impressive number of variables 

that may impact on outcome in a femoral revision using impaction 

allografting. Two series using similar implants and 

similar inclusion criteria may still differ with respect to cement 

(technique, type, viscosity), allograft (source, consistency, 

pretreatment with radiation or freeze-drying), surgical approach, 

and aftercare, to name a but a few potentially important 

factors. The effects of most of these variables have on results 

in this especially complex technique have yet to be described. 

However, nearly every clinical series of impaction grafting 

has inferred histological healing or incorporation of the cancellous 

allograft from plain radiographs. The largest series 

of biopsies following impaction grafting demonstrated 

histological bone healing in all cases. 

While initial series reported were, in general, performed with 

less than ideal instruments, and with implants that were not 

designed to meet the needs of all revision cases, more recent 

improvements in instrumentation and therefore surgical 

technique, as well a larger variety of stem types have helped 

reduce the incidence of complications. However, due to the 

excellent long term results and ease of performance extensively 

coated cementless stems and the common use of 

extended trochanteric osteotomies the technique is used 

more rarely now then when it was first introduced in most of 

North America. It does however remain a useful technique 

in specific cases of massive bone loss and patulous canals 

which would require massive cementless stems.



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REVISION STRATEGY AT 

THE FEMORAL LEVEL 

Laurent Sedel 

Hôpital Lariboisiere (APHP) and University 

of Paris (France) 

Femoral revision is frequent, due to femoral loosening , thigh 

pain, recurrent dislocation, osteolysis or sepsis. Whatever 

the reason, with the exception of some difficult septic cases, 

our strategic approach is similar. Some of our expertise concern 

femoral stem retrieval. Our reconstruction strategy is 

different if we are revising total hip in active and young patient 

or if it is an old and inactive one. 

First step is always a large “en bloc” tissue excision. For old 

and inactive, it is sometimes possible to retain the stem if 

not loosened and perform an “in cement” cementation; In 

this group we select usually metal or alumina on polyethylene 

couple and cemented implants; In young and active, we select 

alumina on alumina combination which resumed in 

cementless acetabular fixation, and cementless or cemented 

stem depending on stem retrieval method. 

Stem retrieval of a well fixed cementless stem is performed 

via a large transtrochanteric approach associated with a transfemoral 

one. Repair is performed using cerclage and long 

cemented stem with or without HA/TCP granules impacted. 

Cement retrieval is at the moment performed since 4 years 

using Ultra sound (Oscar*) material, which in our hand is very 

successful specially for retractor retrieval. This allows easy 

retrieval without fenestration. Then medullary canal is reamed 

in order to receive either a cemented or sometimes a cementless 

stem, depending on the bone quality. 

Frequently we used a modified Link technique replacing 

allogenic morcellised bone by hydroxyapatite granules (45 

cases). This can be done either with a cemented or a cementless 

stem. 

In case of very severe bone loss and osteolysis, we performed 

massive allogenic bone transplant associated with long cemented 

stem and distal HA granules with cement. (18 cases). 

As we usually performed one stage revision for septic cases, 

strategy is not different; It is only in selected cases with many 

sepsis recurrences and specially aggressive bacteria that 

we performed a two stage procedure. 

Our goal is always to get a step down to keep the maximum 

living bone; and also to get the best functional outcome permitted. 

RESULTS WITH CEMENTLESS STEM 

REVISION 


Orthopädische Krankenhaus Gersthof, 

Wien (Austria) 

THE MANAGEMENT OF PERIPROSTHETIC 

FEMORAL FRACTURES UTILIZING 

A CEMENTLESS TOTAL HIP REVISION 

SYSTEM WITH MODULAR DISTAL 

FIXATION 

Robert A. Fada, MD; Jose A. Rodriguez, MD; Thomas K. 

Tkach, MD; Tyler McKee, DO; Jodi F. Hartman, MS; and 

Michelle L. Wright, BS 

Lenox Hill Hospital. New York (USA) 

Periprosthetic femoral fractures after total hip arthroplasty 

are increasing in frequency and pose a significant technical 

challenge to the orthopaedic surgeon. The purpose of this 

study was to perform a multi-center, retrospective review of 

periprosthetic femoral fractures managed with a specific 

cementless, corundumized, modular revision femoral component 

and report the results at a minimum 1-year follow-up. 

Pre op planning is performed to try and predict the implant 

length and depth of penetration. When possible, a 5 cm extent 

of bone contact is sought within the distal fragment. The 

surgical technique involves removal of the implant in place, 

using the fracture site to gain access to any remaining points 

of fixation. When necessary for proximal spot welds, the 

proximal fragment can be split longitudinally as in a Wagner 

technique to allow access to the fixation points. The fracture 

is exposed only to the extent necessary to allow implant extraction 

and obtain reduction. Every attempt is made to protect 

the quadriceps fibers attachment, particularly to the distal 

fragment. The distal fragment is reamed through the fracture 

site to assure proper positioning, and checking the reamer 

position using an image intensifier. Once distal fragment 

position and contact is assured, the proximal fragment is 

reamed to allow clear implant passage. The distal stem is 

then inserted to the predetermined position while maintaining



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90 

a loose fracture reduction, followed by final cerclage cable 

tightening, and proximal reaming and implantation. 

Between 1998 and 2006, 3 orthopaedic surgeons at 3 institutions 

revised 20 total hip arthroplasties with periprosthetic 

fractures using this particular femoral component design. All 

fractures occurred as a result of minor trauma, such as a fall 

to the floor, or spontaneous fracture. No trochanteric osteotomies 

were performed. Allograft struts were utilized in 11 (55.0%) 

cases. The study population was comprised of 15 (75.0%) 

females and 5 (25.0%) males, with a mean age of 75.4 years 

(range, 43.6 – 87.5) and a mean BMI of 26.9 (range, 17.0- 

35.6). Vancouver fracture classification distribution was as 

follows: 2 (10.0%) B1; 3 (15.0%) B2; 14 (70.0%) B3; and 1 

(5.0%) C. Mean follow-up was 3.6 years (range, 1.1 – 7.5). 

The mean Harris Hip Score at the most recent follow-up was 

84.6 (range, 65.0 – 100.0) and the mean pain sub-score of 

39.2 (range, 30.0 – 44.0), corresponding to good clinical results 

with mild to no pain. The majority (70.0%) of patients 

exhibited Brooker I heterotopic ossification. Eighteen (90.0%) 

patients had no subsidence. Subsidence of 2- and 6-mm 

occurred in 2 (10.0%) cases with stable and integrated femoral 

components. Distal portions of all fractures healed; however, 

2 (10.0%) fractures with proximal splitting of the femur became 

trochanteric nonunions in distally well-fixed stems. One (5.0%) 

patient experienced a dislocation approximately 3 months 

postoperatively, which was successfully treated with a closed 

reduction. No revisions have occurred. These promising shortto 

mid-term results, with minimal complications and no revisions, 

suggest that this specific cementless, modular, corundumized, 

tapered femoral component is a viable management 

option for complex periprosthetic hip fractures. 

Distal fixation was achieved in all cases despite the complexity 

of the fractures, with the majority occurring at or just below 

the stem in patients with poor proximal femoral bone stock 

CAMBIOS ÓSEOS TRAS LA UTILIZACIÓN 

DE VÁSTAGOS LARGOS EN CIRUGÍA 

DE REVISIÓN 

Eduardo García Cimbrelo 

Hospital La Paz, Madrid (Spain) 

El aflojamiento del componente femoral produce frecuentemente 

graves defectos óseos que hacen difícil la cirugía 

de revisión. La revisión quirúrgica mediante vástagos cementados 

y vástagos no cementados con poro proximal ha 

demostrado resultados dudosos en pacientes con defectos 

óseos. La técnica de injerto impactado, si bien ha permitido 

obtener buenos resultados, es una técnica difícil y no exenta 

de complicaciones. 1,2 Wagner desarrolló un vástago recto 

no cementado de permitía una buena fijación diafisaria distal 

al defecto óseo preexistente, observando excelentes resultados 

clínicos e incluso una regeneración ósea de dichos 

defectos. 3 A pesar de estos buenos resultados, fueron 

frecuentes las luxaciones y lo hundimientos del implante 4-6 

En una serie de 79 vástagos Wagner SL (Sulzer, Zimmer 

Win-terthur, Switzerland) utilizados en cirugía de revisión 

con un mínimo de 5 años de seguimiento, 6 hubo 11 luxaciones 

pero sólo un vástago aflojado y relacionado con un mal relleno 

del canal. La probabilidad acumulada de no tener una 

revisión del vástago por cualquier causa fue 92.3% (86.8%- 

97.8%) en el mejor escenario posible. Se observó regeneración 

ósea proximal definida en 50 caderas pero fue asociada 

a ausencia de defectos mayores (p=0.01). En conjunto, se 

pudo encontrar un aumento de las corticales lateral y medial 

al final del seguimiento (p10mm (8 caderas) 

se relacionó con un pobre relleno del canal (p=0.003). 

La osteoporosis preoperatoria según los grados de Moreland 

7 determinó el “stress shielding” postoperatorio. Un grave 

“stress shielding” se observó en 5 caderas en los que incluso 

desapareció parte de la cortical lateral proximal. El grosor 

de la cortical medial aumentó una media de 15% con el paso 

del tiempo (p



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92 

produce resultados satisfactorios en cirugía de revisión femoral 

con defectos óseos proximales, siendo frecuente la 

fijación radiográfica estable y la consolidación de posibles 

fracturas periprotésicas. Aunque sin relación clínica, de momento, 

es frecuente el engrosamiento de la cortical medial 

del fémur y la disminución de la cortical lateral. Las frecuentes 

complicaciones, como hundimientos y luxaciones, requieren 

de una adecuada planificación preoperatorio y de cirujanos 

expertos. Recientes series refieren buenos resultados utilizando 

prótesis modulares en casos con graves defectos 

óseos, aunque habrá que esperar seguimientos más largos. 

10 

REFERENCIAS 

1. Gie GA, Linder L, Ling RS, Simon JP, Slooff TJ, Timperley 

AJ. Impacted cancellous allografts and cement for revision 

total hip arthroplasty. J Bone Joint Surg [Br] 1993; 75- 

B:14-21. 

2. Ornstein E, Atroshi I, Franzèn H, Jonson R, Sandquist P, 

Sundberg M. Early complications after one hundred and 

forty-four consecutive hip revisions with impacted morselized 

allograft bone and cement. J Bone Joint Surg 

[Am] 2002; 84-A: 1323-8 

3. Wagner H. Revision of femoral stem with important loss 

of bone stock. In Gallinaro P (ed) Postgraduate lectures 

of the first European Federation of National Associations 

of Orthopaedics and Traumatology (EFORT). (European 

Instructional Course Lectures EFORT. vol1) Paris, 

Masson; 1993, p 64-74. 

4. Kolstad K, Adalberth G, Mallmin H, Milbrink J, Sahlstedt 

B. The Wagner revision stem for severe osteolysis. 31 

hips followed for 1.5-5 years. Acta Orthop Scand 1996; 

67:541-4. 

5. Bohm P, Bischel O. Femoral revision with the Wagner 

SL revision stem, Evaluation of one hundred and twentynine 

revisions followed for a mean of 4.8 years. J Bone 

Joint Surg [Am] 2001; 83-A:1023-31. 

6. Gutierrez del Alamo J, Garcia-Cimbrelo E, Castellanos 

V, Gil-Garay E. Radiographic bone regeneration and 

clinical outcome with Wagner SL revision stem. A 5-year 

to 12-year follow-up study. J Arthroplasty 2007;22:515- 

524. 

cases. Acta Orthop Scand 1994;65:505-8. 

7. Moreland JR, Moreno MA. Cementless femoral revision 

arthroplasty of the hip. Minimum 5 years follow-up. Clin 

Orthop 2001;393:194-201. 

8. Paprosky WG, Greidanus NV, Antoniou J. Minimum 10year 

results of extensively porous-coated stems in revision 

hip arthroplasty. Clin Orthop 1999;369:230-42. 

9. Nadaud MC, Griffin WL, Fehring TK, Mason JB, Tabor 

Jr OB, Odum S, Nussman DS. Cementless revision total 

hip arthroplasty without allograft in severe proximal 

femoral defects. J Arthroplasty 2005;20:738-44. 

10. Sporer SM, Paprosky WG. Femoral fixation in the face 

of considerable bone loss. The use of modular stems. 

Clin Orthop 2004;429:227-31. 

VÁSTAGO ENCERROJADO IRH 

Antonio Navarro, Lluís Carrera 

Hospital Universitario de Traumatologia Vall d'Hebrón, 


Los defectos femorales proximales severos representan un 

problema importante en la cirugía de revisión del vástago 

femoral. 7,12 

La incidencia y severidad de la pérdida de hueso en la metáfisis 

proximal asociada al aflojamiento aséptico en las artroplastias 

totales de cadera continua incrementándose. El reto para 

los cirujanos que realizan estas revisiones es determinar cual 

es el mejor método para fijar el implante a un fémur con un 

gran defecto óseo proximal y que proporcione estabilidad 

tanto para la carga como para la movilidad de la articulación. 

Igualmente, la técnica debe ser duradera y permitir la restauración 

del déficit óseo inicial. 

Las revisiones con vástagos femorales cementados presentan 

resultados impredecibles, y a medio plazo son poco satisfactorios. 

8,10,19,28 

Gie y Ling 11 proponen la utilización de aloinjerto impactado 

para restaurar el defecto óseo proximal y la cementación de 

un vástago liso. Los resultados a medio plazo tampoco son 

satisfactorios. 22,25,27 

Otras técnicas utilizadas son los vástagos largos de anclaje 

distal y superficie porosa más o menos extensa. Resultados 

clínicos pobres. 29,17,20,23,29 

Vástagos cónicos de anclaje distal, (Wagner), el hundimiento 

y la luxabilidad del implante limitan su utilización. 13,14,15,21,26 

Los vástagos modulares de anclaje metafisario (S-ROM) 

favorecen la restauración ósea metafisaria proximal y presentan 

resultados esperanzadores a medio plazo. 4 

Aloinjertos masivos combinados con vástagos cementados. 

12,16,24 

Vástagos con bloqueo distal para conseguir estabilidad inicial. 

32 

En nuestro centro hemos desarrollado un implante cilíndrico 

con encerrojado distal, recubierto de hidroxiapatita. El vástago 

de revisión IRH (Interlocking Revision Hip). En este 

artículo presentamos los resultados obtenidos en los 60 primeros 

casos en los que se utilizó esta ténica de revisión con 

un seguimento medio de 22 meses y mínimo de 12 meses.



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94 

MATERIAL Y MÉTODO 

Desde Noviembre de 1998 hasta Enero del 2004 se ha 

utilizado en 80 revisiones de vástago femoral. Presentamos 

los resultados de los 60 primeros vástagos IRH, que correspondían 

a 54 pacientes, intervenidos desde Noviembre de 

1998 hasta Enero del 2002. Las edades en el momento de 

la revisión oscilaban de 58 a 81 años, con una media de 

edad de 71 años. Distribución por sexo, 20 hombres y 34 

mujeres. La causa de revisión era por aflojamiento aséptico 

en 58 caderas, 1 caso de fractura patológica y una fractura 

periprotésica. Las revisiones se realizaron por fracaso de 

prótesis cementadas en 50 casos y no cementadas en 10 

casos. En 56 casos era la primera revisión, en 3 casos la 

segunda y en un caso el tercer recambio de vástago. En la 

mayoría de ocasiones se recambió el acetábulo excepto en 

4 casos. La valoración preoperatorio de los defectos femorales 

se realizó utilizando la clasificación de la AAOS. En 10 

casos correspondía al tipo I, en 19 al tipo II, en 30 al tipo III 

y en uno al tipo IV. 

Todas las revisiones se realizaron con el vástago IRH. El 

vástago IRH (Interlocking Revision Hip) es una aleación de 

titanio recubierta con doble cobertura de alúmina e hidroxiapatita. 

Diseño cilíndrico con surcos longitudinales que aumentan 

en profundidad a medida que nos acercamos a la 

punta del vástago, por lo que su comportamiento biomecánico 

es cónico provocando un gradiente elástico progresivo. 

El diseño cilíndrico permite aumentar las zonas de contacto 

óseo. Presenta una ángulación de 135º y por lo tanto un offset 

suficiente para disminuir el riesgo de luxación. El diseño 

de este vástago se basa en la estabilización distal diafisaria 

inicial, favorecida por la posibilidad de bloqueo distal con 

uno o dos pernos dependiendo de la longitud del vástago. 

Esta estabilización primaria favorece la osteointe-gración 

secundaria metafiso-diafisaria gracias a la cobertura de 

hidroxiapatita. El encerrojado distal permite el ajuste longitudinal 

y la rotación del implante, permitiendo tantas pruebas 

de estabilidad articular como sean necesarias antes del 

bloqueo definitivo. El bloqueo proximal y la aleta dorsal permiten 

el cierre de la osteotomía y con ello la correcta reinserción 

y tensión de los pelvitrocantéreos. Los vástagos 

tienen longitudes desde 210 a 310 mm y diámetros desde 

12 a 22 mm con incrementos de 2 en 2 mm. Todos los vástagos 

femorales han sido insertados con cabezas de 28 mm, 

aunque también puede colocarse con una cabeza de 32 

mm si el caso lo requiere. 

Todos los casos han sido intervenidos en decúbito lateral, 

abordaje posterior, osteotomía transtrocantérica ampliada 

de más de 12 cm (todos los casos excepto 1, fractura patológica). 

Después de extraer el implante, el cemento y las 

membranas se realiza una revaloración del defecto óseo 

preoperatorio, que suele ser siempre mayor al planificado. 

Iniciamos el fresado progresivo de la diáfisis femoral 1 o 2 

mm más del tamaño elegido. Se valora la adaptación y estabilidad 

del implante con un adaptador de prueba. A continuación 

se introduce el vástago definitivo, se reduce la 

articulación y se ajusta en rotación y en longitud. Cuando la 

la adaptación del implante es la deseada procedemos al 

bloqueo distal, con uno o dos pernos dependiendo de la longitud 

del vástago (a partir de 270 mm). Por último, procedemos 

al cierre de la osteotomía con el tornillo de bloqueo proximal 

y/o cerclajes metálicos a través de la aleta dorsal. 

Colocamos injerto homólogo, si es necesario y cerramos el 

campo operatorio dejando dos redones profundos de aspiración 

a baja presión. 

Postoperatorio: La conducta postoperatoria ha variado a 

medida que hemos ganado experiencia sobre el comportamiento 

del implante. El tiempo de encamamiento ha pasado 

de 12-15 días a 2-3 días dependiendo de las características 

del paciente. A las 48 horas se retiran los drenajes y se 

inicia sedestación según tolerancia. Si la sedestación es 

bien tolerada se inicia la deambulación con ayuda de bastones 

y carga parcial progresiva. La media de estancia hospitalaria 

es de 10 días. El control clínico y radiológico se realiza de 

forma periódica a las 6 semanas, 3 meses, 6 meses y al 

año. Posteriormente se controlan cada año. A los 3 meses 

todos los pacientes son autorizados a cargar todo el peso 

en la extremidad afecta con o sin ayuda de bastones. 

Todos los pacientes han sido evaluados clínicamente con un 

seguimiento mínimo de 12 meses excepto un paciente que 

falleció a consecuencia de un TEP masivo en el posto-peratorio 

inmediato. Seguimiento medio 22 meses. Se utilizó la escala 

de Harris para la valoración funcional del paciente. 

Valorándose en los controles la presencia o no de dolor en 

el muslo. 

El estudio radiológico seriado, proyección anteroposterior 

y lateral de cadera incluyendo el fémur distal en 59 vástagos 

útiles para el seguimiento. Se compararon las radiografias 

del postoperatorio inmediato con las tomadas al año de 

evolución. Dado que la confirmación histológica no era posible 

se determinó la estabilidad del implante siguiendo los 

criterios de Engh. 9 . para la osteointegración. La estabilidad 

se clasificó en integración, integración fibrosa estable y en 

inestable. La valoración del hundimiento vertical se realizó 

utilizando los criterios de Callaghan et al. Hundimientos 

superiores a 5 mm fueron considerados como significativos. 

También se valoró la presencia de líneas de radiolucéncia 

y su progresión. 

Se realizó la valoración global de todos los estudios radiológicos 

de cada paciente. 

RESULTADOS 

La media de la puntuación preoperatorio según la escala de 

Harris era de 42.5 puntos en los 60 vástagos. Un paciente 

había fallecido en el postoperatorio inmediato a causa de 

un TEP. En el momento de la valoración, media de seguimiento 

22 meses, la puntuación media fue de 81.6 puntos. 

En el momento de la revisión los resultados obtenidos fueron 

calificados como excelentes en 50 de los 59 casos (85%), 

buenos en 6 casos (10%) y malos en 1 caso (1,5%). En ningún 

caso existía dolor en cara anterior del muslo.



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96 

El mal resultado fue un paciente en el que por error no se 

practicó correctamente el encerrojado distal y progresivamente 

determinó un hundimiento del vástago. Se solventó 

colocando un implante primario modular recubierto de 

hidroxiapatita. 

En los 59 pacientes útiles para el seguimiento se valoró la 

radiología seriada. Utilizando los criterios de Engh para la 

valoración de la estabilidad del implante. 58 pacientes mostraban 

integración global del implante en zona diafisaria 

(98%). Se valoró el hundimiento siguiendo los criterios de 

Callaghan, un implante presentaba hundimiento superior a 

5 mm, lo que condicionó el recambio del mismo. En ningún 

caso existían zonas de radiolucencia lineal ni progresiva. 

Todas las osteotomias consolidaron, incluso aquellas en las 

que no se aportó injerto óseo. 

Ningún paciente presentó dolor en la cara anterior del muslo. 

Complicaciones: Dos rupturas del implante, 1 fractura periprotésica 

peroperatoria se la cortical femoral anterior que 

fue tratada de forma consevadora y que no influyó en la 

evolución clínico-radiológica del implante. Dos migraciones 

del tornillo proximal que obligó a su retirada en un caso. Un 

fallo del encerrojado distal que condicionó el posterior hundimiento 

y fracaso del implante. Una luxación postoperatoria 

a los 3 meses tras un traumatismo de baja energía. 

DISCUSIÓN 

La utilización de vástagos cementados en la cirugía de revisión 

presenta peores resultados que en la cirugía primaria cuando 

no incluye restauración biológica del déficit óseo. Los porcentajes 

de rerevisión oscilan desde el 9% 10,28 al 49% 8,19 . 

La restauración del déficit óseo es necesaria para mejorar 

los resultados. Existen distintas técnicas quirúrgicas. 

. 11 Técnica de Exeter. La utilización de aloinjerto troceado 

permite la reconstrucción ósea cuando el fémur proximal 

es sufucientemente estable en defectos cavitarios puros o 

combinados que pueden convertirse en continentes. Presenta 

un elevado índice de complicaciones, hundimientos 

y fracturas periprotésicas, por lo que sus indicaciones son 

muy restringidas. 22,25,27 

. Los vástagos largos de anclaje distal y superficie porosa 

presentan resultados difíciles de valorar debido a la gran 

variabilidad en su diseño y en la extensión de la superficie 

porosa. El dolor en la cara anterior del muslo y el stressshielding, 

que disminuye la capacidad de restauración ósea 

proximal, hacen que no recomendemos su utilización de 

17,23,29. 9,20 

forma sistemática. 

. Vástagos recubiertos de hidroxiapatita. Las características 

biológicas de la hidroxiapatita favorecen la formación ósea, 

reconstrucción del defecto óseo y osteointegración del 

implante. 2,5,6 

. Los vástagos modulares de anclaje metafisario (S-ROM) 

presentan resultados esperanzadores a corto plazo con un 

6 % de fracasos a los 6 años. La fijación metafisaria favorece 

la hipertrofia endostal y cortical reconstruyéndose el defecto 

óseo femoral proximal. No tenemos experiencia en su utilización. 

4 

. Aloinjertos masivos combinados con vástagos no cementados. 

Head, McLaughlin y Gross presentan resultados 

aceptables. Es una técnica a valorar en casos de grandes 

defectos óseos que exijan la utilización de aloinjertos estructurales 

masivos. 12,16,24 

. En 1987, Wagner presentó una técnica de revisión con un 

vástago cónico largo de anclaje diafisario distal con excelente 

regeneración ósea proximal espontánea. El anclaje del 

vástago se consigue por implantación en la diáfisis femoral 

tras el fresado cónico de la misma. Wagner recomienda su 

utilización en presencia de defectos femorales proximales 

utilizando la via transfemoral o trocanterectomía ampliada. 

Basándose en la fijación diafisaria distal del vástago cónico, 

se busca una fijación primaria perfecta que favorezca la 

ulterior osteointegración por aposición ósea entre los surcos 

protésicos. 31 

Las publicaciones de Hartwing, Kolstad, Grüning y Michelinakis 

están de acuerdo en tres hechos importantes: 

a) Reconstrucción biológica del fémur proximal en la mayoría 

de los casos, incluso sin aporte de injerto óseo. 

b) Hundimiento del vástago 

c) Luxabilidad del implante. 

d) Planificación preoperatoria exigente. 13,15,21,26 

Böhm y Bischel tras revisar 129 vástagos con un seguimiento 

medio de 4.8 años mostraban un hundimiento medio de 5.9 

mm y 7 casos de luxación. 3 

Gutierrez y Garcia Cimbrelo en una reciente revisión de 55 

vástagos con un seguimiento medio de 6 años presenta hundimientos 

mayores a 3 mm en 11 caderas y 7 luxaciones. 14 

En una reciente revisión realizada en nuestro centro, 88 

casos con un seguimiento medio de 6.5 años hemos podido 

observar: 

. Hundimiento en el 45 % de los casos con una media de 

13.7 mm. 

. Fracturas femorales periprotésicas, per y postoperatorias 

en el 16 % de los casos. 

. Luxación en el 6.8 % de los casos. 

. Regeneración ósea proximal en el 65 % de los casos. 

. Contacto metal-hueso 27.57 mm. Mucho menor de lo recomendado, 

de 7-10 cm. 31 

Creemos que el vástago de Wagner es una buena opción 

para el tratamiento de los aflojamientos protésicos con importantes 

defectos óseos femorales proximales, aunque presenta 

un índice de hundimiento importante y una elevada tasa de 

luxabilidad que exige un encamamiento postoperatorio largo.



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98 

La planificación preoperatoria es compleja para determinar 

la longitud y el grosor del implante. Presenta poco off-set lo 

que facilita la luxación. Es dificil ajustar la longitud y la 

anteversión, ya que una vez impactada es imposible la vuelta 

atrás. 

CONCLUSIONES 

Creemos que el vástago IRH puede ser una buena alternativa 

para el tratamiento de los aflojamientos asépticos de los 

vástagos femorales con grandes pérdidas de hueso 

metafisario. 

Al inicio utilizabamos el vástago IRH solo en casos de grandes 

defectos óseos femorales o fracturas periprotésicas. 

Sin embargo, los excelentes resultados obtenidos hasta la 

fecha han hecho que se halla convertido en la técnica de 

elección para la mayoría de los recambios de vástago femoral 

en nuestro centro. 

BIBLIOGRAFIA 

1. Blackley. HR, Davis. AM, Hutchinson. CR, Gross AE: 

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stock in revision arthroplasty of the hip. J Bone and Joint 

Surg. 83A: 346. 2001. 

2. Bhamra. MS, Rao. GS, Robson. MJ: Hydroxyapatite-coated 

prostheses: difficulties with revision in 4 cases. Acta 

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5. Buoncristiani. AM, Dorr. LD, Johnson. C, Wan. Z: Cementless 

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7. D´Antonio. J, McCarthy. J, Bargar. W, Borden. L, Cappelo. 

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8. Engelbrecht. D, Weber. F, Sweet. M, and Jakim I: Long 

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9. Engh. Ch, Culpepper. W, and Kassapidis. E: Revision of 

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10. Estok. D, and Harris. W: Long term results of cemented 

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11. Gie. GA, Linder. L, Ling. RS, Simon. JP, Slooff. TJJH, 

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12. Gross, A, Blackley. H, Wong. P, Saleh. K, Woodgate. I: 

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13. Grünig. R, Morscher. E, Ochsner. PE: Three-to 7 year 

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18. Iorio. R, Eftekhar. N, Kobayashi. S, and Grelsamer. R: 

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20. Krishnamurthy. AB, MacDonald. SJ, Paprosky. WG: Five 

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21. Kolstad. K, Adalberth. G, Mallmin. H, Milbrink. J, Sahlstedt. 

B: The Wagner revision stem for severe osteolysis. 31 

hips followed for 1.5-5 years. Acta Orthop Scand. 67:6, 

541-4. 1996. 

22. Leoplold. S, Rosenberg. A: Current status of impactation 

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23. Malchau. H, Wang. YX, Kärrholm. J, Herberts P: Scandinavian 

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24. McLaughlin. J, Harris. W: Revision of femoral component 

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27. Ornstein. E, Atroshi. I, Franzen. H, Johnsson. R, Sandquist. 

P and Sundberg. M: Early complications after one 

hundred and forty-four consecutive hip revisions with 

impacted morselized allograft bone and cement. J Bone 

and Joint Surg., 84-A: 1323-1328.2002. 

28. Raut. VV, Siney. PD, Wroblewski. BM: Outcome of revision 

mechanical stem faliure using the cemented Charnley´s 

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405-10. 1996. 

29. Souminen. S, and Santavirta. S: Revision total hip arthroplasty 

in deficient proximal femur using a distal loadbearing 

prosthesis. Ann Chir Gynaecol. 85:3, 253-62. 

1996. 

30. Sugimura. T, Tohkura. A: THA revision with extensively 

porous coated stems. 32 hips followed 2-6.5 years. Acta 

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31. Wagner. H: A non allogaft press fit alternative. Current 

Concepts in Joint Replacement. Orlando. December 1995. 

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with distal interlocking. J Arthroplasty 19 (1):27-33. 2004. 

LONG TERM RESULTS IN HA-COATED 

REVISION HIP ARTHROPLASTY 



Netherlands 

The goal of hip revision surgery is to restore longevity of 

pain-free function that has been disturbed by one of the 

many failure mechanisms in arthroplasty. 

Main challenges include: 

- provide stable fixation of the new implant 

- provide stable joint resistant against dislocation 

- restore the bone that has been damaged by osteolysis and 

stress-shielding 

Progress in fixation biology through the use of HA-coatings 

has permitted expanded indications for the use of HA-coated 

implants in revision arthroplasty, especially on the femoral 

side. HA-coatings have been used in revision arthroplasty 

since 1986 in several stages of evolution. The first generation 

of implants using HA-coated Omnifit stems with now 20 years 

follow-up has resulted in excellent long term survival although 

the scope of application was somewhat limited as it is actually 

a primary stem. Long term follow-up of 63 cases initially with 

average age of 53 years at time of revision surgery and 61% 

multi-revisions showed survival rates at minimum 15 year 

follow-up of 92%. 

Based upon the same design characteristics the evolutionary 

HA-coated Restoration stem became available in 1997 with 

variable stem lengths and diameters followed by the even 

more flexible modular successor in 2005. They have greatly 

expanded the versatility and success rate even in complex 

revision surgery. Although the numbers have increased, 

follow-up is still limited but based on the excellent results of 

previous generations where upon its design was based we 

can expect excellent and reliable long term results. Initial 

complication rate is low and the early mechanical failure rate 

is below 2%. 

FRACTURAS PERIPROTÉSICAS 

DE FÉMUR 

Carles Mestre 

Hospital de l’Esperança. IMAS. Barcelona (Spain) 

TWO- TO FIVE-YEAR FOLLOW-UP OF 

MOSTLY TYPE III FEMORAL DEFECTS IN 

REVISION THR TREATED WITH THE LINK 

MP STEM 

Rodriguez JA, Fada R, Murphy SB, Rasquinha VJ, 

Ranawat CS 

Lenox Hill Hospital. New York (USA) 

BACKGROUND 

Femoral bone deficiency has been shown to adversely affect 

the results of revision THR. Tapered titanium modular stems 

allow distal fixation of the fluted, conical portion of the stem 

in the remaining bone, and may be a more versatile approach 

to fixation in the setting of proximal bone loss. 

METHODS 

One hundred and two consecutive hips with proximal bone 

loss underwent revision femoral reconstruction between 1998 

and 2002 at 3 centers using the Link-MP modular stem. Fortythree 

hips had Mallory Type 3C femoral deficiency. Ninety-



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seven hips were followed for an average 45 months (range 

24-72). Initial distal fixation was achieved, and the proximal 

segment was chosen to optimize hip center of rotation. 

RESULTS 

Clinically, mean Harris hip score improved from 36 to 84 

(range 54-99). Radiographically, 94 hips were considered 

stable, with no circumferential lucencies at the distal fixation 

surface. Lucencies around the proximal segment were 

common but did not compromise performance. Two hips 

with type 3C deficiency migrated and required reoperation, 

and one additional hip with type 3C defienciecy developed 

a periprosthetic fracture that required revision. They were 

each successfully revised to a larger implant of the same 

design. Five other hips had non-progressive migration of 1- 

2 mm. One stem in a 320 lb man fractured, and was revised 

to a larger implant. Ten hips dislocated, with 6 being revised 

by altering the modular proximal segment with no further 

sequelae. There were 3 periprosthetic fractures successfully 

treated with ORIF. 

CONCLUSIONS 

Distal fixation is well maintained with this distally fluted, 

tapered titanium stem in the face of severe distal bone loss.



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Jueves, 10 de abril 

Thursday, 10th April 

CADERA / HIP 

Acetábulo de revisión 

Infecciones 

Revision acetabulum 

Infections 


Unicompartimentales 

PTR, MIS y Navegación 

Rótula 

Unicompartimentals 

TKA, MIS and Navigation 

Patella 

Moderadores / Moderators: Michael Wroblewski, Xavier Flores, 

Peter McLardy-Smith, Aaron Rosenberg, Hendrik P. Delport

JUEVES / THURSDAY 

106 

08.30 - 10.45 h 

CADERA / HIP 

Acetábulo de revisión / Revision acetabulum 

Moderador: Michael Wroblewski 

ACETABULAR REVISION: BONE LOSS 

IS NOT THE ONLY ISSUE 

Aaron G Rosenberg MD 

Professor of Surgery Rush University Medical College. 


Hemispherical ingrowth sockets have been accepted as the 

standard treatment modality for acetabular revision surgery 

in over 90% of most contemporary reports. Multiple series 

now demonstrate the success of this technique in both consecutive 

series as well as in specific settings. This technique 

seeks a viable concentric bleeding rim of bone which will 

contain the cup. Up to a third of the cup may be uncovered 

utilizing this technique, as long as the cup is in contact with 

host bone over 50% of its surface and rigid fixation (a mechanically 

stable construct at the time of implantation) is obtained. 

In addition to understanding the technique required to implant 

these component successfully, the surgeon must be aware 

of those settings where the construct is not likely to work so 

that he can plan for alternative techniques when needed. 

Contraindications for the use of a cementless socket include: 

lack of intrinsic mechanical stability prior to the placement 

of screws, less than 50 percent host bone contact, bone necrosis 

from previous radiation, pelvic discontinuity, when we 

need a cup so large to get a fit that it’s not available, or when 

we use a bulk graft where we don’t have greater than 50 

percent host bone contact. If the rim is lost superiorly or 

posteriorly, so that the implant is not stable to mechanical 

testing, Some sort of supplemental stabilizing material must 

be employed. Traditionally this has been bulk graft . In many 

of these cases an anti-protrusio cage overlying structural 

graft has been used in the past. Unfortunately relatively high 

intermediate term failure rates have led to alternative solutions 

including the use of Tantalum trabecular metal (TM) augmentation 

of bony defects coupled with trabecular TM cups. 

Tantalum, when compared to traditional implant materials, 

has a higher volumetric porosity, a lower modulus of elasticity 

and higher interfacial friction characteristics that make it an 

attractive alternative. In addition to being manufactured into 

cementless hemispheres it is also offered in the form of modular 

augments that can be utilized to fill acetabular defects. 

These augments are intended to be used in a manner similar 

to a structural allograft, however they have the advantage of 

allowing bony-ingrowth while potentially allowing for particulate 

grafting in the structure of the augmentto stimulate 

bone stock restoration (with structural integrity enhanced by 

the underlying metallic construct. Recent reports have described 

the use of cementless acetabular components fabricated 

from tantalum in the setting of revision total hip arthroplasty 

with good results in primary arthroplasty. 

An additional issue is pelvic disassociation, which may occur 

in settings where bone loss is not a prominent issue. This 

complex problem can range from the easily diagnosed where 

the x-ray is diagnostic (though this is relatively rare) to the 

occult, which can only be diagnosed with concerted effort at 

evaluating the integrity of the acetabulum after complete 

debridement. This “non-union” of the acetabulum has been 

treated historically with acetabular fixation plates and this 

still remains the mainstay of treatment in cases with grossly 

mobile dissociations. Following fixation of the fracture acetabular 

reconstruction can then follow the principles outlined 

above. However recent work with TM augments and bone 

fillers have led to an “expansion” technique of filling defects 

with the augments and then “expanding” the acetabular 

reconstruction with a large cup, wedging the pelvic defect 

apart and so providing stability at the fracture site while placing 

compressive streseses on the acetabular reconstruction. 

Initial, short-term results have been good in the revision 

setting with novel new use of the TM augments, but await 

confirmation with longer follow-up. 

The lack of structural support for the implant or adequate 

bone for component fixation is not the only factor accounting 

for failure in acetabular revision surgery. Multiple series of 

acetabular revision show that recurrent dislocation plays a 

significant role in revision arthroplasty failure. Dislocation is 

a complex, multi-factorial issue and occurs up to 20x more 

frequently in revision as opposed to primary series! In particular, 

liner exchange for poly wear has been associated 

with a high dislocation rate. Issues of head/neck/skirt size 

relationships are similar in primary and revision surgery as 

are the contributions of leg lengthening and offset to hip 

stability. Reducing the occurrence has been a focus for clinicians 

as much of the issues regarding bone support and 

fixation have been comprehensively addressed. 

Factors which may be comprormised during revision surgery, 

include soft tissue tension, abductor muscle quality and



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component position. Abductor muscle quality should be 

maintained by avoiding denervation of the glutei and avoiding 

potential trochanteric osteotomy union problems. Soft tissue 

tension can be influenced by the amount of scar release 

needed to perform surgery and the ability of the surgeon to 

use residual capsule to reconstitute the soft tissue envelope. 

Attention to the details of scar excision, and capsular repair 

are thus essential to minimize instability. 

Bone loss itself may alter the surgeon’s perception of appropriate 

positioning of the component. Loss of anterior or 

posterior bone may alter the appearance of relative acetabular 

version, while superolateral loss may alter what appears 

to be appropriate abduction. Careful intra-operative monitoring 

of component position relative to the pelvis and not the local 

aceatbular margin is neccesary to prevent acetabular component 

malpositioning. 

REFERENCES 

· Beaule PE, Ebramzadeh E, Leduff M, Prasad R, Amstutz 

HC: Cementing a liner into a stable cementless acetabular 

shell. J Bone Joint Surg 80A: 929-934, 2004. 

· Kaplan SJ, Thomas WH, Poss R: Trochanteric advancement 

for recurrent dislocation after total hip arthroplasty. J 

Arthroplasty 2:119-24, 1987. 

· Pellici PM, Bostrom M, Poss R: Posterior approach to total 

hip replacement using enhanced posterior soft tissue repair. 

Clin Orthop 355: 324-328, 1998. 

· Sioen W, Simon JP, Labey L, Audekercke R Van: Posterior 

transosseous capsulotendinous repair in total hip arthroplasty. 

A cadaver study. J Bone Joint Surg 84A:1793-1798. 

· Hopper RH, McAuley JP, Engh CA: Modular component 

revision of recurrent dislocation of a total hip replacement in 

selected patients. J Bone Joint Surg 83A:1529-1533, 2001. 

· LaPorte DM, Mont MA, Pierre-Jacques H, Peyton RS, 

Hungerford DS: Technique for acetabular liner revision in 

a non-modular metal-backed component. J Arthroplasty 

13:348-350, 1998 

· Berry DJ, Lewallen DG, Hanssen AD, et al.: Pelvic discontinuity 

in revision total hip arthroplasty. J Bone Joint Surg 

81A:1692-702, 1999. 

· Dearborn JT, Harris WH: Acetabular revision arthroplasty 

using so-called jumbo cementless components: an average 

7-year follow-up study. J Arthroplasty 15:8-15, 2000. 

· Lachiewicz PF, Poon ED: Revision of a total hip arthroplasty 

with a Harris-Galante porous-coated acetabular component 

inserted without cement. A follow-up note on the results at 

five to twelve years. J Bone Joint Surg 80A:980-4, 1998. 

· Leopold SS, Rosenberg AG, Bhatt RD, et al.: Cementless 

acetabular revision. Evaluation at an average of 10.5 years. 

Clin Orthop 369:179-86, 1999. 

· Paprosky WG, Perona PG, Lawrence JM: Acetabular defect 

classification and surgical reconstruction in revision arthroplasty. 

A 6-year follow-up evaluation. J Arthroplasty 9:33- 

44, 1994. 

· Templeton JE, Callaghan JJ, Goetz DD, et al.: Revision of 

a cemented acetabular component to a cementless acetabular 

component. A ten to fourteen-year follow-up study. 

J Bone Joint Surg 83A:1706-11, 2001 

· Whaley AL, Berry DJ, Harmsen WS: Extra-large uncemented 

hemispherical acetabular components for revision total hip 

arthroplasty. J Bone Joint Surg 83A:1352-7, 2001. 

IMPACTION GRAFT TECHNIQUE 

IN THE SOCKET 


Princess Elisabeth Orthopaedic Hospital 


TANTALIO EN CIRUGÍA DE REVISIÓN 

Agustín Blanco Pozo 

Jefe de Servicio de Cirugía Ortopédica y Traumatología 

Complejo Hospitalario General Yagüe-Divino Vallés 

Burgos (Spain) 

INTRODUCCIÓN 

En los últimos tiempos los Cirujanos Ortopédicos, así como 

el resto de las especialidades, estamos realizando lo que 

hemos convenido en llamar “cirugía de lo imposible”. 

Tanto los profesionales como los pacientes que atendemos 

realizamos diariamente gestos quirúrgicos que llevan en si 

mismos unas dificultades, impensables hace apenas 25 

años. Cirujanos y pacientes se enfrentan cada día a situaciones 

más complicadas, con una dificultad añadida, son 

realizadas en pacientes muy jóvenes que exigen unas necesidades 

muy grandes; Hablamos así una vez más de la 

llamada “cirugía de lo imposible”. 

La llegada de los metales porosos ha permitido rescatar 

acetábulos que prácticamente, estaban hace muy poco tiempo, 

condenados a formar parte de una cadera colgante. 

Surgen en el mercado el Tantalio (metal trabecular), el 

Regenerex (titanio poroso) y el Tritanium (titanio poroso).



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Por la única razón de ser el primero en aparecer en el mercado 

utilizamos en nuestra cirugía de rescate habitual en 

un porcentaje importante, desde Enero de 2003, el Tantalio, 

lo que se define al menos en la industria como lo más parecido 

al hueso. 

MATERIAL Y MÉTODOS 

El periodo de utilización de la bandeja metálica de Tantalio, 

en nuestra experiencia comprende un periodo que va desde 

Enero de 2.003 hasta la actualidad; los reseñados para la 

presentación que nos ocupa se cierran a Diciembre de 2007, 

para ofrecer resultados, o impresiones iniciales despreciando 

los intervenidos a lo largo del último año. 

El número total de implantes realizados es de 158, todos 

ellos concebidos para su utilización en revisión de cirugía 

de cadera, empleando 7 de ellos como acetábulos primarios 

y 151 como acetábulos de revisión; los 60 iniciales eran los 

constituidos exclusivamente por Tantalio que nos obligaba 

a cementar sobre ellos el inserto de polietileno, del 61 en 

adelante hemos utilizado la bandeja metálica constituida por 

Tantalio que en la concavidad de la misma está realizada 

en Titanio con lo cual evitamos la cementación del inserto. 

Actualmente nuestra práctica se dedica cada día con más 

frecuencia a la cirugía de rescate de la cadera estimando 

que nuestros gestos representan en relación con los implantes 

primarios entre un 25 y un 30% en los últimos años. 

La edad media está en 67,5 años, siendo el sexo femenino 

el que predomina en nuestra serie. El seguimiento comprende 

el tiempo transcurrido entre 4 meses y 5 años, el número 

de pacientes es de 151 pacientes, habiendo desechado 

anteriormente para está presentación los más recientes, los 

realizados en el pasado 2007 por lo que el número real del 

que comunicamos impresiones está en 107 pacientes, todos 

ellos con una cirugía al menos de entre 1y 5 años. 

Utilizamos sistemáticamente la vía antero-lateral (Watson- 

Jones), la fricción siempre que es posible (recambio de ambos 

componentes) cerámica-polietileno, recambiamos como 

no podía ser de otra forma el componente acetabular en 

todos los casos que presentamos y en el 65% ambos componentes; 

el 78% de los vástagos sustituidos son sin utilización 

de cemento y el resto con utilización del mismo, siendo 

nuestra intención utilizar siempre que es posible vástagos 

diseñados como primarios (signo inequívoco de una buena 

constitución esquelética en el receptor) y cuando esto no es 

posible, generalmente vástagos modulares. 

Los diámetros utilizados de insertos y cabezas en estos 

primeros 107 casos, han sido fundamentalmente de diámetro 

28 mm, mientras que los realizados en el último año, y de 

los que no informamos los resultados, prácticamente son 

todos de 32 mm; cotilos retentivos en 6 de los 107 casos 

que consideramos, siendo la tendencia en el último año a 

ir en aumento dado que en 44 pacientes intervenidos en el 

2007 se han utilizado 11 acetábulos retentivos. 

RESULTADOS 

Las complicaciones presentadas son semejantes a las de 

cualquier otra técnica que se usa para la resolución de 

rescates en prótesis totales de la cadera de difícil resolución. 

Hemos valorado: 

- Luxaciones que aumentaron de manera peligrosa en nuestros 

primeros 60 pacientes, esto es en los intervenidos con 

bandejas metálicas de Tantalio que nos obligaban a cementar 

el inserto de polietileno. 

- Infecciones 

- Fracturas trocantéricas 

- Calcificaciones heterotópicas 

- Trendelemburg 

- Dismetrías mayores de 3 cm 

- Reintervenciones 

Los resultados radiológicos iniciales tienden todos a informar 

de una formidable osteointegración habiendo podido comprobar 

la misma en algún explante procedente de reintervenciones 

de casos que por complicación se vieron abocados 

a un segundo gesto quirúrgico; también por la comprobación 

de la osteointegración de clavos de Tantalio utilizados en 

cirugía de necrosis de la cadera por otros cirujanos, dado 

que nuestra experiencia en esta técnica es cero. Igualmente 

hemos podido comprobar la osteointegración en preparaciones 

vistas a microscopía con la ayuda del doctor M. 

Fernández Fairen. 

CASOS CLÍNICOS 

Se presentan diferentes casos de diferentes tiempos y 

dificultades. 

DISCUSIÓN Y CONCLUSIONES 

Queremos informar razonablemente de IMPRESIONES 

INICIALES, el tiempo transcurrido es insuficiente para 

dogmatizar con conclusiones: 

1º) Resultados clínicos excelentes (valoración de Harris) 

2º) Resultados radiológicos excelentes (comprobados en 

alguno de los pacientes por estudios anatómo-patológicos 

por piezas explantadas. 

3º) Estabilidad excelente desde el inicio (hemos utilizado en 

todos los casos tornillos de anclaje). 

4º) Posibilidad de añadir cuñas, lo que conforma una bandeja 

modular (en nuestra casuística con poca experiencia) 

estabilizada desde el inicio. 

5º) Posibilidad de utilizarse en discontinuidades pélvicas 

facilitando y acortando de manera importante el tiempo 

quirúrgico. 

6º) Debemos informar de un sorprendente comportamiento, 

muy bueno, evidentemente cuando todavía ha trascurrido 

poco tiempo sospechando que es un muy buen método 

para utilizar en parte de nuestra cirugía realizada en caderas 

de alta dificultad; igualmente con la aparición del 

Tantalio, nuevo material así como por ejemplo con la tribología 

alúmina-alúmina se inicia una época de nuevas 

complicaciones.



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ANILLOS DE SOSTÉN, DE REFUERZO 

Y ANTIPROTRUSIÓN EN 

RECONSTRUCCIÓN ACETABULAR 

A. Murcia Mazón. MA. Suárez Suárez, M. Fernández 

Fairén, A. Murcia-Asensio 

Universidades de Oviedo y Politécnica de Cataluña. 

Hospital de Cabueñes. Gijón (Spain) 

INTRODUCCIÓN 

La artroplastia total de cadera, (ATC) es una de las intervenciones 

con mejor relación coste-beneficio, y gracias a ella 

muchos pacientes mejoran su calidad de vida. La ATC tiene 

una vida limitada y con el paso del tiempo y su utilización 

puede aparecer el aflojamiento mecánico del implante que 

puede expresarse en la zona de interfaz de uno o de ambos 

componentes. La causa de este aflojamiento es multifactorial, 

y en él influyen no sólo el paciente y los factores quirúrgicos 

sino también factores mecánicos y biológicos. 

Con el fin de mejorar sus resultados tanto en cirugía primaria 

como en la reconstrucción acetabular de un componente que 

se ha movilizado se dispone de los anillos, que son estructuras 

metálicas que dependiendo de su forma de actuar e indicación 

pueden ser: de soporte; de refuerzo y antirprotrusión. 

TIPOS DE ANILLOS 

Los más utilizados pueden ser de tres tipos: 

Anillos de sostén 

Introducidos por M Müller en los años sesenta para aumentar 

la rigidez de la fijación de los cotilos cementados en pacientes 

con mala calidad ósea. Utilizados en cirugía primaria por la 

escuela del diseñador, pero posteriormente fueron apareciendo 

modificaciones en forma de ganchos o aletas con el 

fin de dar más estabilidad primaria al implante acetabular que 

consiste en un inserto de polietileno cementado. De éste tipo 

son los anillos SL de Müller y el SL de Müller-Ochsner. 

El anillo de Müller tiene forma de semibóveda con borde externo 

evertido en la periferia para encajar al reborde acetabular 

y con múltiples agujeros para tornillos. Posee un gran agujero 

en el fondo que permite la colocación de injerto óseo antes 

de la cementación, ya que el relleno óseo es imprescindible 

para lograr que su borde interno apoye perfectamente en el 

fondo. Su objetivo es distribuir las fuerzas de presión en una 

mayor área del techo acetabular, cubriendo los cuadrantes 

superior y posterior. Sobre este armazón se cementa una 

cúpula de polietileno de la misma medida del anillo. 

Anillos de refuerzo 

Los primeros anillos de refuerzo están basados en el empleo 

de mallas o redes metálicas ideadas en la década de los 70 

por Naghachan y Zippel. Posteriormente Ganz modificó este 

diseño para crear un anillo con prolongación del borde inferior 

mediante un gancho de anclaje a la escotadura acetabular, 

idea también propuesta por Kerboull. Eichler ideó un anillo 

de refuerzo con forma de corona con aletas triangulares convergentes 

dirigidas hacia el interior del acetábulo preparado 

para cementar la copa de polietileno y reforzar las paredes 

del acetábulo, pero no para colocar injertos. 

Aparecen modificaciones de estos anillos de sostén que se 

convierten en anillos de refuerzo pudiendo recibir en su interior 

un inserto de polietileno no cementado y que se ajusta al 

soporte metálico externo con distintos tipos de fijación. 

De forma parecida y con una transición similar a los anillos 

anteriores aparecen los anillos de reconstrucción o antiprotrusivos 

que tienen su principal indicación en la cirugía reconstructiva 

acetabular y que genéricamente reciben el nombre de 

Anillos antiprotrusión, llamados también cajas o jaulas ya 

que se trata de armazones metálicos con distinta morfología 

y diseño que aparte de reconstruir el acetábulo impiden que 

este pueda ir protruyendo en la pelvis. Existen diversos modelos 

siendo los más utilizados en nuestro medio el de Burch- 

Schneider, la cruz de Kerboull o el Restoration GAP II. El 

anillo de Ganz dispone de un gancho para insertarse en el 

agujero obturador. 

Dentro de este tipo de anillos existe una gran variedad de 

ellos, con mayor o menor complejidad en su configuración 

pero que todos ellos tienen la misma finalidad. Del mismo 

modo conforme se complica su diseño se adaptan más a la 

cirugía de revisión o reconstrucción, que a la cirugía primaria 

donde tienen su mejor indicación los más sencillos que son 

los de soporte o sostén. 

El modelo Octopus es modular formado por un anillo en forma 

de araña recubierto de hidroxiapatita con pestañas para fijación 

al ilíaco y un gancho de fijación al agujero obturador, al 

que se le acopla una cúpula y el inserto de polietileno permitiendo 

la utilización de injerto óseo. 

El dispositivo Burch-Schneider es una jaula de reconstrucción, 

que presenta prolongaciones proximales y distales para el 

atornillado al ileon e isquion. Permite el atornillado interior 

múltiple con tornillos de 6,5 mm y la colocación de injerto en 

el trasfondo. Se complementa con una cúpula de polietileno 

cementada de diámetro igual al elegido. La pestaña inferior 

para el isquion puede atornillarse o incrustarse en el hueso 

para logar una mayor estabilidad. 

El modelo Partial Pelvis Replacement similar al anterior, posee 

dos prolongaciones craneales de diversos tamaños y se presenta 

con un gancho para el agujero obturador o con pestaña 

caudal atornillada. El conjunto se completa con un componente 

acetabular cementado. Permite el empleo de injertos estructurales 

para la reconstrucción de las paredes y el techo acetabular. 

El sistema de refuerzo acetabular GAP II (Graft Aumentation 

Prosthesis), es también una “jaula” de reconstrucción. Se 

compone de un fondo de cotilo en aleación de titanio con



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múltiples perforaciones para fijación con tornillos, con dos 

placas metálicas perforadas moldeables para la fijación al 

ileon y un gancho inferior de fijación al borde inferior y pared 

posterior del acetábulo. Permite la orientación independiente 

durante la cementación del núcleo de polietileno para evitar 

complicaciones en cuanto a inestabilidad del montaje. 

Con la utilización de estos dispositivos de refuerzo se pretende 

emplear la menor cantidad posible de injerto estructural, 

aunque generalmente sí precisan aloinjerto triturado e impactado. 

El objetivo que pretenden es restituir en la medida de 

lo posible el centro de rotación de la cadera y conseguir una 

estructura acetabular sólida que permita un soporte estable 

al componente de revisión y proteger los injertos óseos durante 

su fase de remodelación e incorporación para restaurar 

la reserva ósea, siendo ideal en estos casos la corticalización 

del fondo acetabular y la organización trabecular del injerto. 

Por su novedad merece un apartado especial los anillos de 

tantalio que tienen dos componentes, uno metálico perforado 

que permite su atornillado al hueso receptor, que recibe en 

su interior un inserto de polietileno cementado para evitar 

los micromovimientos que pueden existir entre ambos componentes. 

El tantalio es un material bioactivo, muy poroso que 

permite y facilita la osteointegración. Disponen de suplementos 

en forma de cuñas ó aumentos y centradores que permiten 

la reconstrucción acetabular sin injertos. 

Dentro de los anillos que utilizan el tántalo como material 

similar al tejido óseo, hay que distinguir un concepto nuevo 

de reconstrucción acetabular que consiste en la combinación 

de los sistema anteriores y es el cup-cage que está indicado 

como sistema de elección en el tratamiento de la discontinuidad 

pélvica. 

Este tipo de reconstrucción acetabular ha sido introducido 

por Paprosky, Gross y Lewaleen, como tratamiento electivo 

en los grandes defectos acetabulares y en la discontinuidad 

pélvica. Consiste en implantar un anillo de tantalio de gran 

diámetro, aunque incluso su introducción pueda producir una 

distracción en la hemipelvis correspondiente. Dentro se coloca 

un anillo antiprotrusión de Burch-Schneider con una aleta 

que se introduce en el espesor del isquion y la otra se atornilla 

al ilion con lo que salta en puente y estabiliza el cotilo de tantalio 

previamente implantado. Existe la posibilidad de atornillar 

ambos componentes metálicos. El inserto es cementado y 

en casos de especial indicación puede ser constreñido. 

Con este tipo de reconstrucción, cup-cage, los resultados 

publicados por sus diseñadores son muy alentadores. 

CLASIFICACIÓN DE LOS DEFECTOS ACETABULARES 

Se han propuesto diversas clasificaciones. Así Gustilo y 

Pasternak establecen cuatro tipos; en el I sólo hay una pérdida 

mínima; en el II, hay un ensanchamiento y adelgazamiento 

de las paredes del acetábulo pero no hay defectos en las 

paredes; en el tipo III hay defectos en las paredes y en el 

tipo IV un colapso masivo global. 

La Academia Americana de Cirujanos Ortopédicos clasifica 

los defectos acetabulares en tres amplios grupos, segmentarios, 

cavitarios y combinados. Un defecto segmentario es 

el que significa una pérdida completa en el hemisferio de 

soporte del acetábulo, incluyendo la pared medial. Los defectos 

cavitarios representan una disminución volumétrica 

de hueso de la cavidad acetabular, incluyendo la pared medial, 

pero la cavidad acetabular y el reborde acetabular 

permanecen intactos. 

La clasificación de Paprosky, tiene la ventaja de describir de 

forma progresiva las lesiones, así como cuantificar la magnitud 

de los defectos óseos a partir de proyecciones radiográficas 

simples. Se basa en la comparación radiográfica de la 

anatomía ósea del acetábulo normal con el acetábulo lesionado. 

Estos hallazgos se complementan con los encontrados 

durante el procedimiento quirúrgico. Es la más utilizada y 

asienta en los siguientes criterios radiológicos: integridad de 

la línea de Köhler, lisis del isquion, deterioro de la “U” radiológica 

o lágrima y grado de migración superior del componente 

acetabular. Se distinguen tres grados de defectos: I, II y III. 

El defecto tipo I presenta un deterioro mínimo del techo y 

de las paredes. El acetábulo óseo mantiene su forma hemisférica, 

sin defectos en los bordes, y las columnas tanto anterior 

como posterior están intactas. 

El defecto tipo II distorsiona la forma de herradura del cotilo 

normal, que es secundaria a la destrucción ósea de las 

paredes anterior, posterior, interna o del techo. El techo tiene 

forma ovalada, y la migración es menor de 2 cm en dirección 

superomedial o lateral, con una destrucción mínima 

del trasfondo acetabular. La lisis tanto del isquion como de 

la lágrima son mínimas, indicando la integridad del anillo y 

de la columna posterior. Según la magnitud del defecto se 

subdividen en tres grupos dependiendo de la localización del 

defecto óseo: 

Tipo II-A; el defecto dominante del techo es superomedial. 

Las pérdidas óseas en las paredes anterior y posterior 

son pequeñas, por lo que es posible el anclaje de un 

nuevo implante acetabular y además estable. 

En el tipo II-B, además del defecto del techo existe una 

migración superolateral del componente acetabular. 

Significa un defecto del techo del acetábulo mayor que 

el grupo anterior estando en parecidas circunstancias 

las paredes anterior y posterior. 

En el tipo II-C el defecto óseo principal se encuentra 

localizado en el trasfondo del acetábulo. Las columnas 

anterior y posterior se encuentran indemnes. 

Los defectos tipo III, se caracterizan por presentar extensas 

pérdidas óseas. La movilización del componente 

acetabular es superior a 3 cm medidos a partir del borde 

superior del agujero obturador, ó ascenso superior a 2 

cm del centro de rotación de la cadera. Como en el apartado 

anterior se distinguen dos subgrupos según la 

extensión del defecto localizado como si de un reloj se 

tratara para localizar la extensión del defecto óseo. En el 

tipo III-A, el segmento horario se localiza entre las 10 y



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las 2, la gota en lágrima está parcialmente lesionada; el 

componente acetabular se encuentra dentro de la pelvis, 

y las columnas anterior y posterior no permiten por 

su osteolisis el anclaje estable de un cotilo convencional. 

El segmento horario que corresponde al tipo III-B se 

sitúa entre las 9 y las 5 horas, persistiendo menos de un 

50% de hueso apropiado para la fijación del cotilo. En 

la radiografía el ascenso de la cúpula es superior a los 

3 cm, la gota en lágrima está completamente obliterada 

y la línea de Köhler se ha destruido. Existe además un 

desplazamiento intrapélvico del componente acetabular. 

INDICACIONES 

Las indicaciones de los distintos tipos de anillos y cajas es 

muy diversa. Los anillos de soporte están indicados en la 

cirugía primaria en casos de debilidad de la estructura ósea. 

Los de refuerzo y antiprotrusivos se implantan en la cirugía 

de revisión dependiendo de la intensidad o magnitud del 

defecto óseo, reservando la combinación descrita como cupcage 

para los graves defectos tipo III y la discontinidad 

pélvica. 

TÉCNICA QUIRÚRGICA 

La vía de acceso a la articulación de la cadera debe ser la 

habitual para cada cirujano pero la más utilizada es la vía 

posterior que permite una exposición amplia de ambos 

componentes protésicos. Es extremadamente útil en casos 

seleccionados poder extraer el componente femoral para 

facilitar la reconstrucción acetabular; y una vez realizada 

recurrir a la técnica de cementación en el cemento. 

RESULTADOS 

Los resultados cuando se respetan las indicaciones y se 

siguen los pasos de la técnica quirúrgica descritos son 

generalmente buenos en la mayoría de las series publicadas. 

Se debe reconocer que en la mayoría de las reconstrucciones 

acetabulares, se necesita con frecuencia injertos óseos que 

se combinan con otras técnicas como la de los injertos 

triturados e impactados ya que la finalidad de esta cirugía 

es mejorar la reserva ósea del paciente con componentes 

protésicos estables. 

COMPLICACIONES 

Como complicaciones específicas de la utilización de cualquier 

tipo de anillos las más frecuentes son las líneas radiotrasparentes 

entre alguna de las intercaras de los distintos componente. 

Además como en cualquier ATC ,sobre todo si es 

de revisión, se pueden presentar cualquiera de las complicaciones 

habituales en este tipo de cirugías y que no están 

relacionadas con la utilización de los distintos tipos de anillos 

metálicos. 

CONCLUSIONES 

1. Los anillos de sostén se reservan para los casos de cirugía 

primaria de cadera cuando la calidad del hueso es 

insuficiente. 

2. Los anillos de refuerzo y antiprotrusión se utilizan en ca- 

sos de cirugía reconstructiva acetabular dependiendo del 

tipo de defecto óseo, asociados o no a injertos óseos. 

3. El sistema combinado cup-cage está indicado preferentemente 

en los graves defectos y en la discontinuidad 

pélvica. 

4.Para disminuir el número de complicaciones en la reconstrucción 

acetabular se deben respetar y seguir los pasos 

técnicos que caracterizan cada tipo de anillo y su misión. 

BIBLIOGRAFÍA 

1. Gross AE, Goodman S: The current role of structural grafs 

and cages in revision arthroplasty of the hip. Clin Orthop 

429, 192-200, 2004 

2. Saleh KJ, Jaaroszynski G, Woodgate I, Saleh L, Gross 

AE: Revision total hip arthroplasty with the use of structural 

acetabular allograft and reconstruction ring: A case series 

with a 10-year average folllow-up J Arthroplasty 

15:951958, 2001 

3. Paprosky WG, O‘Rourke M, Sporer S: The treatment of 

acetabular bone defects with an associated pelvis 

discontinuity. Clin Orthop 441: 216-220, 2005 

4. Goodman S, Presuman A, Sastamoinen H, Gross A: 

Complications of ilio-ischial reconstruction rings in revision 

total hip arthroplasty. J Arthroplasty 19;436-446, 2004 

5. Gerber A, Pisan M, Zurakowski D, Isler B: Ganz reinforcement 

ring for reonstruction of acetabular defects in 

revision total hip arthroplasty. J Bone Joint Surg 85 A: 

2358-2364, 2003 

6. Kerboull M, Hamadouche M, Kerboull L. The Kerboull 

acetabular reinforcement device in major acetabular 

reconstruction. Clin Orthop 378, 155-168, 2000 

7. Nehme A, Lewallen DG, Anisen AD: Modular porous 

metal augments for treatment of severe acetabular bone 

loss during revision hip arthroplasty. Clin Orhopaedics, 

429, 201-208, 2004 

8. Sthiel JB: Trabecular metal in hip reconstructive surgery. 

Orthopedics, 28,7: 662 – 670, 2005 

9. Herrera A, Martinez AA, Cuenca J, Canales V. Management 

of Types III and IV acetabular deficiencies with the 

longitudinal oblong revision cup. J Arthroplasty 2006; 

21: 857-64. 

10. Wachtl SW, Jung M, Jacob RP, Gautier A. The Burt-Schneider 

antiprotrusio cage in acetabular revision. A mean fololwup 

of 12 years. J Arthroplasty 2000; 15: 959-63 

11. Saleh KJ, Jaroszynski G, Woodgate I, Saleh L, Gross AE. 

Revision total hip arthroplasty with the use of structural 

acetabular allograft and reconstruction ring. A case series 

with a 10-year average follow-up.J Arthroplasty 2000; 15: 

951-8. 

12. Udomkiat P, Dorr LD, Won Y, Longjohn D, Want Z. 

Technical factors for success with metal ring acetabular 

reconstruction. J Arthroplasty 2001; 16: 961-9. 

13. Yoon TR, Rowe SM, Chung JY, et al. Acetabular revision 

using acetabular roof reinforcement ring with a hook. J 

Arthroplasty 2003; 18:746-50. 

14. Pieringer H, Auersperg V, Bfhler N. Reconstruction of 

Severe Acetabular Bone-Deficiency.The Burch-Schneider 

Antiprotrusio Cage in Primary and Revision Total Hip Ar-



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throplasty. J Arthroplasty 2006; 21:489-96. 

15. Gill TJ, Sledge JB, Müller ME. The management of severe 

acetabular bone loss using structural allograt and acetabular 

reinforcement devices. J Arthroplasty 2000; 15:1-7. 

16. Berry D. Antiprotrusio cages for acetabular revision. Clini 

Orthop 2004; 420:106-12. 

17. Hernández-Vaquero D, Gava R, Suárez-Vázquez A, 

Pérez-Hernández D, Fernández-Lombardía J. Anillos de 

reconstrucción en la cirugía de revisión de las artroplastias 

de cadera. Rev Ortop Traumatol 2006; 50:93-9. 

18. Goodman S, Saastamoinen H, Shasha N, Gross A. Complications 

of ilioischial reconstruction rings in revision total 

hip arthroplasty. J Arthroplasty 2004;19: 436-46. 

19. Gross AE, Wong P, Saleh KJ Don´t throw away the ring. 

Indications and use. J Arthroplasty 2002; 17 Suppl 1,162-6. 

20. Berry DJ, Lewallen DG, Hanssen AD, Cabanela ME. 

Pelvic discontinuity in revision total hip arthroplasty. J 

Bone Joint Surg Am 1999; 81A: 1692-702. 

21. Sporer SM, Paprosky WG. The use of a trabecular metal 

acetabular component and trabecular metal augment for 

severe acetabular defects. J Arthroplasty 2006; 21 Suppl 

2: 83-6. 

CEMENTLESS CUPS IN REVISION 

SURGERY: CLINICAL EXPERIENCE IN THE 

LONG TERM 

Jorge O. Galante 

Rush Arthritis & Orthopaedic Institute St. Luke’s Medical 

Center. Illinois (USA) 

We have previously reported the results of using a cementless 

acetabular metal shell (HG-1, Zimmer, Warsaw, IN) for revision 

total hip arthroplasty (THA) in a consecutive series of 138 

hips at a minimum of three, seven and fifteen years postoperatively. 

The current report presents the long-term outcomes 

of these procedures, now at a minimum of twenty years 

postoperatively. 

Repeat acetabular revision with removal of the metal shell 

was required in twenty-two hips (16%); twenty-one of these 

acetabular components were well fixed including nine revised 

for recurrent instability (7%), eight removed for infection 

(6%), and four incidental removals at the time of femoral 

revision surgery (3%); one metal shell was revised for aseptic 

loosening. A liner change was performed for wear and/or 

osteolysis in seven hips, and a liner change was recommended 

in another three hip (18% of the living, unrevised cohort). 

Four cups were identified as radiographically loose; one was 

revised for loosening and the remaining 3 died without 

requiring revision. Survivorship of the metal shell, with revision 

for aseptic loosening or radiographic evidence of loosening 

as the endpoint was 94% at twenty years (95% CI, 91%- 

97%). With failure defined as a repeat acetabular revision 

for any reason, the twenty-year survival was 80% (95% CI, 

77-84%). 

Revision cementless acetabular reconstruction provides 

durable fixation at a minimum of twenty years. At long-term 

follow-up, the re-operation rate for polyethylene wear and/or 

osteolysis, which were previously not seen in this cohort, 

has increased. We continue to use a hemispherical, porous 

coated, titanium metal shell with multiple screws for immediate 

fixation in the majority of acetabular revisions. 

DIFFERENT METHODS TO 

RECONSTRUCT ACETABULUM IN 

CASES OF SEVERE BONE LOSS 


Endo-Klinik. Hamburg (Alemania) 

REVISION SURGERY FOR MEGA - 

DEFICIENCIES INCLUDING NONUNIONS 

OF THE ACETABULUM 

Reinhold Ganz 



In revision surgery of the hip the extent of the acetabular bone 

stock deficiency frequently exceeds the possibilities of 

autograft reconstruction. To overcome such problems several 

ways from bigger implants to allografting have been attempted. 

However the more extreme the deficiency the more difficult 

and laborious is the reconstruction. 

Our experience using massive allograft reconstruction was 

50% component migration in segmental defects but only 10% 

in cavitary defects after 5 to 10 years. As a consequence of 

this information we modified the technique of reconstruction 

by using autograft coverage on allograft surfaces uncovered 

by host bone .The goal was to transform a segmental into 

a cavitary defect. Especially in posterior deficiencies and in 

transacetabular nonunions the stabilisation of the bone 

reconstruction was separated from the cup fixation using 

plates similar to acetabular fracture fixation. 

The paper illustrates the technical aspects and reports on the 

results of a small group of deficiencies with pelvic discontinuity.



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11.15 - 12.00 h 

CADERA / HIP 

Infecciones / Infections 

Moderador: Xavier Flores 

THE DIAGNOSIS AND MANAGEMENT OF 

PERI-PROSTHETIC INFECTIONS 

P McLardy-Smith, B Atkins, H Pandit, T Berendt, N 

Athanasou & the Oxford Hip and Knee Group (Richie 

Gill, David Beard, Vicky Flanagan, Chris Dodd, Max 

Gibbons, Roger Gundle, David Murray, Andrew Price, 

Duncan Whitwell) 


Total hip replacement is probably the most successful operation 

ever devised and other joints, particularly the knee 

are now being successfully replaced. However peri-prosthetic 

infection remains a potentially catastrophic complication. 

Infection rates are reported at between 1- 2% and the risk 

of a peri-prosthetic infection runs over the entire life time of 

the joint. Peri-prosthetic infections can usefully categorised 

as early acute or chronic and late acute or chronic. The 

diagnosis of chronic infections, particularly late ones, may 

be difficult to achieve pre-operatively. Imaging techniques 

and serological testing can be useful but are not as yet 

reliable or specific. Aspiration or closed biopsy are similarly 

unreliable. Any joint revised for any reason may have an 

underlying infection. In a prospective study of 334 consecutive 

hip and knee revisions we sent multiple samples from each 

case for bacteriological and histological analysis. We used 

the histological appearance as the criterion for defining 

infection. By this definition 15% of infected cases were culture 

negative and one positive culture specimen has no predictive 

value for under lying infection. Two or more positive cultures 

out of 5 or 6 samples as a useful predictive value. 

In acute infections, if the components are soundly fixed, 

salvage should be attempted with adequate debridement 

sampling and lavage of the joint. Arthroscopic washout in 

Staphylococcal knee infections has a very poor outcome. 

We would then recommend long term antibiotic therapy. 

Salvage maybe possible in chronic infections, but usually 

the components are loose within the bone and a full revision 

will be required. Frozen section histological analysis of the 

tissue at the time of surgery can differentiate septic from 

aseptic loosening and maybe relied upon to choose between 

a one or a two stage revision. 

INFECTED TOTAL HIP ARTHROPLASTY. 

ONE STAGE REVISION 

B. M. Wroblewski, H. Nagai, P. D. Siney, P. A. Fleming 



One of the most serious complications of THA is deep infection. 

Charnley realised the problem. This led to the development 

of clean air enclosure, total body exhaust suits and the introduction 

of the instrument tray system. Subsequently antibiotics 

were used both systematically and also as an addition to the 

acrylic cement. Occasional deep infection requires further intervention, 

either by removing the implant, or performing one 

or two stage revision. 

It has been the senior author’s practice to undertake one-stage 

revision provided the bone stock was of sufficiently good quality 

to ensure reasonable quality of component fixation. The technique 

is based on the accepted principle of infection management: 

Removal of all foreign body material and infected tissues, 

application of local antiseptics/antibiotics, closure of cavities, 

ensuring stability, drainage, rest, continuation of antibiotics. 

Between January 1974 and December 2001, 185 one-stage 

revisions were carried out by the senior author: 162 had a 

minimum follow-up of 5 years with a mean of 12.3 years (5.1 

– 27.6 years). 138 cases (85.2%) were free from infection. 

Presence of a sinus at revision did not affect the outcome 

adversely – on the contrary - 90.4% were infection free as 

compared with 82.7% of those without a sinus. 

THE MARSA GHOST 


Endo-Klinik. Hamburg (Alemania)



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12.15 - 14.15 h 


Unicompartimentales / Unicompartimentals 

Modereador: Peter McLardy-Smith 

UNICOMPARTMENTALS: OSTEOTOMY, 

INTERPOSITIONAL DEVICE OR 

UNICOMPARTMENTAL? 

Thomas S. Thornhill M.D., John B. and 

Buckminster Brown 

Professor of Orthopedic Surgery, Harvard Medical School 

Orthopedist-in-Chief, Brigham and Women’s Hospital 

Boston Massachusetts 


In the 1970’s and early 1980’s, unicompartmental knee replacement 

(UKA) in our institution was utilized in 30-50% of 

patient’s undergoing arthroplasty for osteoarthritis. With improvements 

in total knee replacements (TKA), difficulties in 

patient selection of UKA and concerns over long-term success 

of UKA this procedure fell out of favor. In the 1990’s only 5- 

8% of osteoarthritic patients in our institution underwent UKA, 

while in other institutions the procedure was abandoned. In 

the past few years, UKA has had a rebirth based primarily 

on the “mantra” of minimal invasive surgery. It is heralded 

as a “interval arthroplasty” or “prelude to a total knee”. While 

the pattern of osteoarthritis has not changed the incidence 

of UKA has risen sharply leading to concerns of patient selection 

and, with minimal exposure, difficulties in interoperative 

joint assessment and component implantation. 

These concerns are validated by a review of the literature 

in the 1970’s and 1980’s, which indicated that the most common 

causes of failure included poor patient selection, difficulty in 

intraoperative decision making when considering UKA vs. 

TKR and technical error during surgery. UKA is contraindicated 

in cases of inflammatory arthritis; significant involvement of 

2 or more compartments, subluxation, significant extra articular 

deformity, or the presence of active or untreated infection. 

UKA is relatively contraindicated in obese patients, 

those with significant chondrocalcinosis and in anterior 

cruciate deficient knees. With these criteria applied only 5- 

8% of osteoarthritic patients should undergo UKA. Have we 

stretched the indications for this procedure? While many 

patients previously considered for tibial osteotomy now may 

be considered for UKA this may explain a portion of the 

increased numbers. The increase utilization of both marrow 

based and cell based therapies for cartilage repair however 

should offset this increase. 

Joint inspection at the time of arthroplasty has always been 

an important factor in considering UKA vs. TKA. The status 

of the uninvolved patella femoral compartments, the presence 

or absence of significant osteophytes, the presence or absence 

of the anterior cruciate ligament, the wear pattern of the involved 

compartment and the extent of inflammation have all 

been considered as important determinants. Another potential 

concern in minimally invasive UKA is the inability to carefully 

inspect the remaining joint. 

Finally, technical issues are a major factor in determining 

the success or failure of UKA. In one series from our institution, 

we found a 17% incidence of technical issues that lead to 

early failure. These included under-correction, over correction, 

component mal-rotation, residual incongruity, non-parallelism, 

instability and wear of the unresurfaced compartments. UKA 

in fact is a technically more demanding procedure than TKA. 

If 70% of the total knees done in the US are done by people 

who do less than 30 a year and if UKA patients represent 

only a fraction of the knee arthroplasties performed, there 

is a question of the critical number necessary to maintain 

proficiency with this procedure. Moreover, UKA through 

minimally invasive techniques often has less instrumentation 

than either TKA or UKA through standard incisions. As component 

systems are driven towards minimally invasive surgery, 

the precision of the instrumentation may necessarily be 

compromised. 

UKA remains a useful procedure for treatment of patients 

with osteoarthritis and minimally invasive techniques certainly 

have an advantage. It is hoped that the problems recognized 

in the 70’s and 80’s are not revisited in this era of minimally 

invasive surgery. Below is an outline of the options available 

to treat Unicompartmental Arthritis. 

Current indications for specific treatment in 

non-inflammatory osteoarthritis 

Arthroscopy- evidence of internal derangement, normal 

alignment, preservation of joint space 

Arthroscopic debridement 

-impinging osteophytes (intercondylar, patellofemoral) 

-sealing techniques (not validated) 

Open debridement-limited



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Marrow stimulation techniques -limited to focal (



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Results better with uni at 6 years 

UKR 76% good 

HTO 42% good 

Results of Failed HTO Converted to TKR 

Neyret et al, 1992 

-TKR post HTO. 

-38 patients, mean 8.5 years post HTO 

-3 year mean follow up 

-as compared with primary TKR these patients decreased 

walking distance and less flexion (p< 0.001) 

- no difference in knee score 

Results of Unicompartmental Arthroplasty 

-Thornhill, Clark et al- UKR results 1991 AAOS 

307 UKAs in 251 patients 

mean age 66.2 years;153 female/98 male 

mean f/up 4.2 years (range 2-9 years) 

90% pain relief 

13 knees revised (4.5%) 

wear- 5 knees 

progression of disease- 5 knees 

loosening - 2knees 

synovitis - 1 knee 

-Advantages of UKR 

preservation of bone stock, ACL, PCL, PF joint 

easier rehabilation than HTO and TKR 

fewer perioperative complications 

less metabolic demand 

Potential as an outpatient arthroscopic procedure 

(Minimally invasive) 

-Disadvantages of UKR 

technically demanding 

difficulty in patient selection 

-Strict contraindications to UKR 

inflammatory arthritis 

multicompartment disease 

severe deformity/subluxation 

non articular deformity 

ACL deficiency 

-Relative contraindications to UKR 

chondrocalcinosis 

? osteonecrosis 

obesity 

Results of Failed HTO Converted to TKR 

Neyret et al, 1992 

-TKR post HTO. 

-38 patients, mean 8.5 years post HTO 

-3 year mean follow up 

-as compared with primary TKR these patients had 

decreased walking distance and less flexion (p< 0.001) 

-no difference in knee score 

Gill, Thornhill et al CORR 321: 10-18, Dec 1995 

-Matched group of failed UKRs and HTOs 

UKRS had more revision problems with bone loss 

HTOs had more problem with exposure 

HTOs had better knee and function scores after revision 

-Results of Failed UKR Converted to TKR 

Levine, Thornhill et al: J Arthroplasty 11(7):797-801, Oct 

1996 

29 Patients (31 knees) failed RBBH UKR 

ave age 72.3 yrs (range(49-88) 

ave weight 179 lbs (range 112 -242) 

interval to revision ave 62 months (7-106) 

ave follow up 45 months (24-104) 

PCL sparing knees 30: One PCL sub TKR 

grafted contained defects 7 

4 tibial and 2 femoral wedges 

no structural grafts 

knee and functional results similar to primary TKR 

-Current indications for UKR 

~8-10% of patients with OA undergoing TKR 

transition patient between HTO and TKR 

elderly patient (especially with bilateral disease) 

INDICATIONS FOR UNISPACER 

IS A UNISPACER A MCKEEVER REVISITED? 

Features of McKeever 

Cobalt Chrome 

Contours to Tibial Surface 

Interpositional 

Micromotion at Tibia 

Similar to Cup Arthroplasty 

Features of Unispacer 

• Polished Cobalt Chrome 

• Conforms to Femur 

• Requires contouring 

• Inserted Arthroscopically 

• Interpositional 

• Only for Medial side 

RESULTS MACINTOSH 

- MacIntosh JBJS 1958 

- Good/excellent in 72 of 103 knees. Min 6 mos follow/up. 

30% fair/poor/failed 

RESULTS MCKEEVER 

Mc Keever Clin Ortho 1960 

- 76 implants 40 knees 1 infected 

Potter and Weinfeld JBJS 1972 

-19 OA Knees. 17-19 good/excellent at 3 years 

-Interpositional, do not stuff 

-Requires tibial micromotion 

- Similar to cup arthroplasty



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• 51 Patients 55 knees 2 died 11 lost 

• 40 Patients 44 knees Unicompartmental OA 

• 39 medial 5 lateral 5-13 yr f/up(ave 8yr) 

• 70% good/excellent 

• 6 knees revised(11%) for pain 

• 11 Knees with subsequent surgery 

• Max of 50% failure 

• Scoring system (demerit) 

- 15 degree flex cont 60-80 degree arc - EXCELLENT 

- 15 degree flex cont 30-60 degree arc - GOOD 

» Scott et al JBJS 67A 1985 


• 61 McKeever’s (61 pts) 1971-78 

• 5 year ave follow-up (2-13) 

• 11 lost ; 11 poor result (18%) 

• 7 revised 

• Long rehab 

- 6-8 weeks bivalve 

- 3 weeks non weight bearing 

- 3 months partial weight bearing 

Emerson and Potter JBJS 67A 1985 

RESULTS UNISPACER 

• Hallock- AAOS 2002 

• 120 patients 

• 10% failure rate 

• Steep learning curve 

• Only 13 patients with greater than 1 year follow-up 

• Not suitable for lateral side 

Freedman- 2002 

40% early failure rate 

UNICOMPARTMENTAL KNEE 

REPLACEMENT: MECHANICAL 

CONSIDERATIONS 


Professor Biomechanics. The Hospital for 

Special Surgery (USA) 

Since the earliest unicompartmental knee replacements were 

developed, the mechanical problems they sought to solve 

were the most difficult for any knee arthroplasty. Unlike total 

knee prostheses, the unicompartmental knee does not enjoy 

the luxury or creating its own alignment, stability, or kinematic 

performance. The alignment of the unicompartmental knee 

must conform to the proscribed geometry of the collateral 

ligaments, the cruciate ligaments, and the articulation constraints 

of the contra-lateral surface. The stability of the knee 

after unicompartmental replacement should ideally mimic 

the natural knee as all the existing ligamentous constraints 

are still present, and the contra-lateral surface geometry is 

functionally suited to these constraints. This condition brings 

about two schools of thought. The first is to provide what 

might be termed an unstable or highly mobile surface couple 

consisting of a relatively flat tibial geometry. The second 

school of thought provides articular surface geometries that 

contribute to kinematic stability. Kinematic performance, a 

combination of knee laxity, constraint and range of motion, 

is controlled by articular surface geometry and placement. 

The desired goal is to replicate the important aspects of the 

original articulation, while at the same time not compromising 

load transfer from the implant to the bone. 

UNICONDYLAR KNEE 

REPLACEMENT 

David Dalury 

John Hopkins Hospital. Baltimore (USA) 

UKAs have enjoyed a minor resurgence in popularity with 

increasing interest in mini-incision surgery. Newer implants, 

improved instruments and better techniques have been 

credited with the procedures new popularity. While the classic 

UKA patient remains an elderly, thin, female with minimal 

deformity there has been more focus on utilization of the 

UKA as an alternative to HTO, and TKA in the younger patient. 

Early results with the newer designed implants will be 

reviewed. 

UNICOMPARTMENTAL KNEE 

ARTHROPLASTY WITH MOBILE BEARING 

Keith R. Berend, MD 

Joint Implant Surgeons, Inc., The Ohio State University, 

Mount Carmel Health System, 

New Albany, Ohio USA 

Since the inception of unicondylar knee arthroplasty, clinicians 

have debated the ideal indications for this conservative 

procedure. Despite being reported more than 15 years ago, 

many surgeons continue to follow the standard indications 

outlined by Kozinn and Scott. These restrictive indications 

and contraindications exclude patients who weigh >82 kg, 

are younger than age 60 years, and who have more than



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minimal erosive changes in the patellofemoral articulation. 

Anterior knee pain, thought to be a sign of significant patellofemoral 

involvement, has also been an exclusion criterion. 

Applying these conservative indications, the percentage of 

patients with osteoarthritic knees who may be candidates 

for unicompartmental knee arthroplasty has been reported 

to be between 2% and 15%. In July 2004, the U.S. Food and 

Drug Administration approved the use of the Oxford Phase 

3 unicondylar prosthesis (Biomet, Warsaw, IN) for implantation 

in unicompartmental knee arthroplasty. Using more liberal 

indications, the implant has proven to be a conservative and 

bone preserving yet long-lasting intervention for anteromedial 

arthritis of the knee. 

The purpose of this study is to investigate the early outcomes 

of Oxford medial unicompartmental knee arthroplasty in 

patients in the United States who do not meet the standard 

inclusion criteria. Spe-cifically, the current study investigates 

the role of obesity, young age, patellofemoral arthritis, and 

isolated medial knee pain on the early outcomes and failures 

of this device. In a large series of 318 unicompartmental knee 

arthroplasties performed in 268 patients, these standard 

preoperative contraindications had no influence on the successful 

outcome of the procedure using the Oxford Phase 

3 device. The con-servative, bone preserving nature and 

long-term survivorship of the Oxford Phase 3 device warrant 

its position at the top of the list of alternatives for treating 

medial disease in the growing middle age population. In 

addition, by restoring the knee to the pre-disease state with 

ligamentous balance and functional kinematics, activity and 

lifestyle are considerably improved to near normal in many 

patients following this con-servative procedure. 

The current series supports the elimi-nation of age, weight, 

presence of patellofemoral joint disease, and anterior knee 

pain from the list of contraindications to unicompartmental 

knee arthroplasty when the Oxford Phase 3 device is used. 

SUGGESTED READING 

1. Kozinn SC, Scott R. Unicondylar knee arthroplasty. J Bone 

Joint Surg Am. 1989; 71:145-150. 

2. Goodfellow J, O’Connor J, Murray DW. The Oxford meniscal 

unicompartmental knee. J Knee Surg. 2002; 15:240-246. 

3. Price AJ, Waite JC, Svard U. Long-term clinical results of 

the medial Oxford unicompartmental knee arthroplasty. Clin 

Orthop Relat Res. 2005; 435:171-180. 

4. Vorlat P, Putzeys G, Cottenie D, et al. The Oxford unicompartmental 

knee prosthesis: an independent 10-year 

survival analysis. Knee Surg Sports Traumatol Arthrosc. 

2006;14:40-45. 

5. Price AJ, Dodd CA, Svard UG, Murray DW. Oxford medial 

unicompartmental knee arthroplasty in patients younger 

and older than 60 years of age. J Bone Joint Surg Br. 2005; 

87:1488-1492. 

6. Rajasekhar C, Das S, Smith A. Unicompartmental knee 

arthroplasty: 2- 12-year results in a community hospital. 

J Bone Joint Surg Br. 2004; 86:983-985. 

7. Pandit H, Jenkins C, Barker K, Dodd CA, Murray DW. The 

Oxford medial unicompartmental knee replacement using 

a minimally-invasive approach. J Bone Joint Surg Br. 

2006; 88:54-60. 

BI-COMPARTMENTAL KNEE 

Alois Franz 

Hospital for Orthopedic Surgery and Sportmedicine 

Marienkrankenhaus, 

Siegen (Germany) 

Total Knee Prostheses have evolved over the years to the 

current mechanically superior anatomic designs and thus 

converting Total Knee Arthroplasty into one of the most successful 

surgical procedures. Future success in improving TKA 

requires attention to the knee prostheses design but also to 

the patient profile and its expectations. Stratification of the 

patients based on different activity levels (demand) and 

pathologies (severity of osteoarthritis, compartmental distribution 

and Soft Tissue affection) must be done in order to 

find the best solution to relief the original symptoms and restore 

the normal motion of the knee. Therefore, following the 

same principle, stratification on the knee port-folios should 

also be driven in order to meet in every single pathological 

case its ideal solution. The Journey DEUCE is the first knee 

device that treats Bi-Compartmental Knee Arthritis while 

leaving the pristine lateral condyle intact (Bone sparing) and 

preserving both ACL and PCL (Soft Tissue sparing) in order 

to improve the proprioception. 

The Surgical Technique has been designed based on a 

Primary TKA in order to facilitate as much as possible the 

procedure. On the tibial side, the medial tibial plateau is 

resected with the aid of an Extramedullary Alignment System. 

On the femoral preparation first the IM canal is opened. The 

Whiteside line or/and Epicondylar lines can be marked to act 

as landmarks for the positioning of the anterior cutting block 

and the determination of the external rotation. After the release 

of the anterior cutting block, the transition point has to be 

marked. This is the most distal part of the lateral condyle 

(where the resection meets the lateral cartilage). This point 

acts as reference for the positioning of the Distal Cutting Block 

system (for its varus/valgus position). After having re-sected 

the medial distal condyle, a 3-in-1 cutting block (anterior 

chamfer, posterior chamfer and posterior condyle cuts) has 

to be placed against the distal and anterior cuts of the femur. 

Once all the cuts are done, the Trial Reduction can be 

performed. If the desired stability has been achieved, the peg 

holes of both femur and tibia are performed.



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Last but not least, the definitive cemented components are 

implanted. 

CONCLUSION 

The Journey DEUCE should allow the patient with a Bi- 

Compartmental Knee osteoarthritis to get treated with a new 

knee device that would suit the best both his pathology and 

expectations while resurfacing only the parts of the knee affected 

and sparing as much as possible bone and soft tissues 

in order to bring him back the closest to his forgotten knee. 

UNICOMPARTMENTAL KNEE ARTHRITIS 

UNICOMPARTMENTAL VS TOTAL KNEE 

ARTHROPLASTY 




MANAGEMENT OF UNICOMPARTMENTAL ARTHRITIS 

The management of uni-compartmental knee arthritis is complex 

for several reasons. Because many viable treatment 

options exist, there is legitimate disagreement about the 

actual utility or relative value of the individual procedures, In 

addition, it is not always easy to assess the degree to which 

the knee is truly diseased in only one compartment and to 

what extent additional compartments are the source of symptoms 

or perhaps more importantly, likely to be subject to 

symptomatic deterioration over time. The age, activity level 

and expectations of the patient are additional factors which 

render the decision making complex. As a consequence, the 

clinician may be faced with a difficult decision making process 

in terms of recommending a specific treatment for the patient. 

In general, when conservative measures have failed, there 

are 5 different options which may be available –some in 

isolation and some in combination including; arthroscopy, 

cartilage restoration procedures, and osteotomy. In general 

these techniques are appropriate for younger patients and 

patients with isolated cartilage defects or lesser degrees of 

arthrosis. For more severe arthrosis and older patients the 

choices are usually between uni-compartmental and total 

knee arthroplasty. Choosing between them may be relatively 

simple, or very complex, depending on the factors discussed 

in more detail below. 

DIAGNOSIS 

Patient History 

The history should include not only current complaints but 

also an assessment of prior non-operative and operative 

treatments and the response to those treatments. Patients 

who have undergone multiple unsuccessful procedures are 

generally better candidates for total rather than unicompartmental 

arthroplasty. The location, character and quantity of 

pain are important, as is the presence of pain at night or at 

rest. In general, patients with pain at rest or at night are 

poor candidates for unicompartmental arthroplasty. Likewise, 

patients with diffuse pain or anterior pain are in general better 

served by total arthroplasty. Patients are specifically questioned 

to determine whether or not they are more symptomatic 

when ascending or descending stairs as this indicates pain 

from the patellofemoral joint. Symptoms of instability and 

mechanical symptoms of knee locking or catching should 

also be documented. It is also important to recognize those 

patients with unrealistic expectations, such as those who 

only experience pain and disability in the context of intense 

physical exertion in whom activity modification or non-arthroplasty 

surgical interventions would be most appropriate 

IMAGING 

Plain Radiographs 

Radiographs obtained should including standing anteroposterior, 

lateral and patellofemoral views. Standing radiographs 

are imperative to detect subtle joint space narrowing 

associated with loss of articular cartilage. A standing view 

with the knee flexed 45 degrees is also useful in identifying 

subtle joint space narrowing. Standing full-length mechanical 

axis views are obtained pre-operatively for operative planning 

and stress views may be obtained to determine whether or 

not the sagital plane deformity is passively correctable. 

Magnetic Resonance Imaging 

Magnetic resonance imaging may occasionally be indicated 

to further evaluate the integrity of the cartilaginous surfaces 

when plain radiographic findings are unclear. Degenerative 

meniscal tears often co-exist with arthritis. In addition, early 

osteonecrosis may only be detectable by magnetic resonance 

imaging. 

Bone Scintigraphy 

Bone scintigraphy can be useful in evaluation patients with 

normal radiographic findings who have symptoms and signs 

of osteoarthritis or may be useful when subtle degeneration 

of the contralateral compartment or patellofemoral joint is 

suspected. 

ARTHROSCOPY 

Arthroscopy allows for the direct visualization of the cartilaginous 

surfaces and for the accurate detection of meniscal 

pathology. There is no data to support its utility in determining 

sutability for unicompartmental arthroplasty. It may however 

be combined therapeutically with unicompartmental arthroplasty 

when contra-compartmental pathology requires arthroscopic 

treatment 

General Pre-requisites 

The general pre-requisites for surgical procedures directed 

to uni-compartmental arthritis include severe damage to the 

cartilage in an isolated compartment, an adequate range of



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motion, absence of inflammatory arthritis or diffuse synovitis 

and the absence of severe instability with relatively well 

maintained range of motion. Significant instability should 

be managed prior to procedures directed to managing the 

cartilage deterioration, but most procedures directed to 

isolated uni-compartmental disease assume that the knee 

is intrinsically stable . 

UNICONDYLAR KNEE ARTHROPLASTY 

In general arthroplasty, including unicondylar knee arthroplasty 

is most appropriate for older, more sedentary patients with 

true isolated uni-compartmental tibio-femoral arthritis. Patients 

with isolated uni-condylar osteonecrosis with reasonable 

amounts of healthy underlying bone to support the component 

are also excellent candidates. Optimal results are obtained 

in non-obese patients without patellofemoral symptoms who 

have functioning anterior and posterior cruciate ligaments 

and range of motion greater than 120 degrees. Minor degrees 

of patello-femoral symptoms and less range of motion may 

be considered, but in general the isolated re-surfacing of the 

joint will not improve these findings. Minimal and passively 

correctable deformity are important pre-requisites for optimum 

results. Some consider that early arthritis isolated to the 

antero-medial aspect of the joint is the ideal indication for 

this procedure. In this setting the presence of a normal 

postero-medial compartment prevents medial collateral ligament 

contracture and renders ligament releases unnecessary. 

More severe involvement of the medial com-partment leads 

to contracture of the ligament and may require some degree 

of release to appropriately balance the joint but more than 

15 degrees of varus is considered the upper limit of acceptable 

deformity. Additionally the patient should not exhibit more 

than one centimeter of medial-lateral translation, this degree 

of instability precludes the likelihood of a durable result with 

uni-compartmental arthroplasty. 

Contraindications for uni-compartmental arthroplasty would 

include tri-compartmental or inflammatory arthritis of the 

knee. Significant patello-femoral symptoms and greater than 

Outerbridge grade 2 chondrosis of the patellofemoral or contralateral 

compartments as determined intra-operatively 

would also be contra-indications. Clinically relevant findings 

of range of motion less than 90 degrees, flexion contracture 

more than 10 degrees and deformity of more than 10 degrees 

of varus or15 degrees of valgus would favor total knee arthroplasty. 

Deficiency of the anterior or posterior cruciate ligaments, 

and certainly clinical evidence of any medial or lateral 

ligamentous instability would also contra-indicate UKA. 

Less rigid contra-indications include the desire to return to 

strenous activities involving running, high impact loading and 

high torque load, obesity as well as unrealistic expectations 

from surgical intervention. This would include patients with 

fibromyalgia or those who have responded poorly to multiple 

previous interventions. 

TOTAL KNEE ARTHROPLASTY 

Total knee arthroplasty is indicated for patients with osteoarthritis 

of the knee who have failed non-operative treatment 

and are not considered to be a good candidate for one of 

the alternative procedures previously mentioned. The majority 

of patients have arthritis affecting two compartments of the 

knee although good results have been reported for the treatment 

of older patients with isolated patello femoral arthritis. 

Excellent long-term results have been reported with survivorship 

exceeding 90% at a follow-up of more than 20 years 

in one recently reported series. Additional evidence indicate 

that patients may obtain higher levels of physical function 

after TKA than do patients who have undergone osteotmy. 

Unicompartmental Arthroplasty versus Total Knee Arthroplasty 

In our experience, it is most common to have to decide between 

total knee and unicondylar arthroplasty than between 

high tibial osteotomy and unicompartmental arthroplasty. 

Deciding between these two options can be difficult. The 

selection criteria for unicompartmental arthroplasty is much 

more exacting than for total knee arthroplasty and thus the 

results may not be as predictable as total knee arthroplasty 

for many surgeons. Specifically, it is unclear how much radiological 

or clinical involvement of the other compartments 

is acceptable and the surgeon must carefully judge how 

much tolerance a particular patient may have for persistent 

pain from the other compartments of the joint that have not 

been resurfaced.



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15.30 - 17.45 h 

CADERA / HIP 

PTR, MIS y Navegación / TKA, MIS and Navigation 

Modereador: Aaron Rosenberg 

NAVIGATION IN TKA. PRINCIPLES 

Francisco Maculé 

Hospital Clínic de Barcelona, 


THE ROLE OF COMPUTER ASSISTED 

SURGERY IN TRAINING SURGEONS TO 

PERFORM TKA 


Northwestern University Feinberg School of Medicine 


SELECTING THE BEST APPROACH 

FOR MIS TKA 

Peter M. Bonutti, MD 

Bonutti Clinic. Effingham, Illinois (USA) 

MIS TKA has been defined primarily based on the Quadriceps 

exposure: 1) Mini-Midvastus (VMO Snip) 2) Modified Median 

Parapatellar (“Quad Saving”); 3) Mini-Subvastus; 4) Modified 

Mini-Subvastus 5) Direct Lateral. All incorporate the principles 

of: 1) reduced incision; 2) quadriceps sparing approach; 3) 

downsized instrumentation; 4) in situ bone cuts. 

We retrospectively evaluated our experience with over 2000 

MIS TKA quad approaches to identify the advantages and 

disadvantages of each of these approaches. 

The Mini-Midvastus (VMO snip) is a straight forward extensile 

approach which can be used on the majority of patients regardless 

of age, weight or deformity. The Modified Median Parapatellar 

(Quad Saving) is technically demanding and requires 

high patient preselection. The approach requires osteotomy 

of the patella first, then the distal femur. Instrumentation, 

especially for patella and distal femoral cut can be difficult and 

accuracy of the cuts has been questioned. The Mini-Subvastus 

is more difficult for anterior femur exposure. It can be quite 

challenging in well-muscled males or in patients with patella 

baja. The Modified Mini-Subvastus allows better exposure to 

the anterior femur. It avoids any questions of denervation of 

the VMO muscle and is extensile. Finally, the Direct Lateral 

Approach is the most complex. It may be most cosmetic 

approach but instrumentation requires Computer Navigation 

and a downsized tibial keel for accuracy. There is a higher 

complication rate with a significant learning curve. 

Overall, MIS TKA is challenging and requires an evolutionary 

approach. Mini-Midvastus (VMO snip) can be a universal 

approach. The Mini-Subvastus approach is theoretically appealing, 

but exposure is technically challenging. The Modified 

Mini-Subvastus approach requires a learning curve but can 

be a universal approach. The “Quad Saving” requires significant 

patient preselection and there are issues of accuracy of 

the bone cuts and higher risk for complication. The Direct Lateral 

approach appears to be the most difficult and has the 

highest potential for complications. Overall, we recommend 

an evolutionary approach to MIS TKA. The Mini-Midvastus 

and the Modified Mini-Subvastus can be techniques which 

can be applied to most patients and are techniques knee 

arthroplasty surgeons can use. 

MIS KNEE. A SOFT TISSUE OPERATION? 


Head department of Orthopaedics AZ Nikolaas 

Hospital St Niklaas. Belgium 

TKA is one of the most beneficial procedures we have today. 

Long-term results have also been outstanding. But performing 

a TKA using less than traditional visualization presents us 

with new problems. 

The hype of MIS has resulted in the observation that most 

surgeons have reduced their incisions to smaller ones. The 

only way to avoid pitfalls is to know where they lie. Injuries to 

the popliteal vessels, the patellar tendon and the medial 

collateral ligament are catastrophic. 

Failure in alignment and position of the components is always 

visible on x-rays. Other non visible anatomic structures (nerves,vessels, 

ligaments,etc.) are at risk during the procedure 

and should be respected. 

Damaging the cutaneous nerves of the knee region can eventually 

lead to neurinoma formation. This not only gives raise



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to numb areas but occasionally can cause extreme pain. 

Some approaches are influencing the innervation of the vastus 

medialis. Different patterns of this nerve can be described. 

Saving the supra- and infra-patellar fat pad has several benefits. 

This is important for the patellar blood supply, but also 

has biomechanical implications and obscures visualization 

of the lateral compartment. 

The medial supporting structures are to be respected. Care 

should also be taken to the postero-lateral corner during the 

balancing and releasing action in this area. Always remember 

the minimal distance between the posterior capsule and the 

popliteal artery in extension and flexion. As shown by prof. M. 

Prettenklieber (Vienna) the distance between the joint capsule 

and the popliteal artery is subject to a high degree of variations 

and ranges from 2 to 37 mm. It may even decrease in flexion! 

The potential pitfalls are iatrogenic! 

Our message is :please take care of the important soft tissues 

during MIS Total Knee Replacement. Therefore we need to 

know anatomy and train our retractor management and assistant 

team choreography. 

REFERENCES 

1. Avoiding the Potential Pitfalls of Minimally Invasive Total 

Knee Surgery. Keith Berend and Adolph Lombardi. Orthopedics 

2005; 28: 1326 

2. Minimal-Incision Total Knee Arthroplasty. M Tenholder and 

Giles Dcuderi. Clin Orthop and Rel Res nr 440,p.67-76, 

2005 

PITFALLS & COMPLICATIONS OF MIS TKA 

Peter Bonutti, MD 


The purpose of this study was to identify the main pitfalls and 

complications associated with minimally invasive total knee 

arthroplasty and to describe and define a set of techniques 

and tips for avoiding or compensating for these difficulties. 

To provide this evaluation, we retrospectively evaluated a 

single author’s series of 1,500 consecutive minimally invasive 

total knee arthroplasties. The surgeries included in this study 

were defined in terms of four categories that minimized the 

invasiveness of the TKA:1) Using an incision of 10 centimeters 

or less; 2) Reducing the amount of soft tissue disruption, 

specifically damage to the quadriceps muscle which typically 

incorporates splitting of this muscle; 3) Trying to not dislocate 

the patella (subluxing the quadriceps mechanism rather than 

completely everting the patella); and 4) Minimizing the amount 

of knee joint dislocation (tibial-femoral dislocation). 

The study design is a retrospective analysis of patients who 

underwent minimally invasive total knee arthroplasty from 

January 1999 to January 2007. The data collection included 

implant type, need for lateral release, incision size, tourniquet 

time, and any intraoperative and postoperative complications. 

Preoperative and postoperative data included age, gender, 

weight, diagnosis, and Knee Society scores including pain, 

stability and range of motion. In addition, a radiographic review 

was conducted. 

The entire study cohort included 1022 unilateral TKAs and 

478 bilateral TKAs in 641 males and 853 females. The mean 

Knee Society objective scores improved from 42.9 points 

preoperatively to a mean of 93.8 points postoperatively. 

Similarly, the Knee Society Functional Scores improved from 

48.7 points to 95.2 points at final followup. 

There were 62 complications that required any type of intervention 

of the 62 revision total knee arthroplasties, 35 were manipulation 

under anesthesia, 17 were arthroscopic procedure, 

4 soft tissue release and retained cement removal, 4 were full 

component revisions (2 for deep infection,1 for suspected 

infection but not negative culture,1 for traumatic instability), 3 

were tibial component revisions (aseptic loosening, pain), 1 

was polyethylene spacer exchange for extensive wear, 1 was 

a femur revision, and 1 was a revision from a cemented system 

to a cementless for PMMA allergy diagnosed by a dermatologist. 

Although the overall tibiofemoral angles averaged 5.4° valgus, 

we had some radiographic outliers. Several patients demonstrated 

with tibia varus of greater than 3°. These patients are 

at increased risk for early aseptic tibial loosening. 

Clearly there are risks associated with any new surgical techniques 

and most complications occurred early in the learning 

curve, although, complications did occur throughout the entire 

series. Nevertheless, MIS TKA principles can provide excellent 

results, fast recovery, and perhaps less postoperative pain 

with improved quadriceps function. 

MIS IN TKA 


Warwick Medical School. Coventry (Great Britain) 

MINI-INCISION TKA 

David Dalury 

John Hopkins Hospital. Baltimore (USA) 

Smaller incisions are a natural consequence of surgeon confidence 

and experience, instrument design and patient demands. 

Several authors have found no increase in complications with 

smaller incisions while others have documented more problems 

with alignment of implants and wound problems when trying 

to minimize the skin incision. While the theoretical advantages 

of Mini incision TKR are easier recoveries for patients, surgeons 

should never compromise outcomes simply for a smaller incision. 

This paper will discuss the pros and cons of MiTKR.



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18.15 - 19.15 h 


Rótula / Patella 

Moderador: Hendrik P. Delport 

THE SUCCESS OF ISOLATED 

PATELLAR COMPONENT REVISIONS 

FOLLOWING FAILED METAL-BACKED 

PATELLAR TKA 

Victor M. Goldberg, M.D, Ryan Garcia, M.D 

Matthew Kraay, M.D 

Case Medical Center, Department of Orthopaedics Cleveland, 

Ohio (USA) 

Metal-backed patellar components have been associated 

with high rates of failure often causing surface damage to the 

femoral component. Retention of a superficially damaged 

femoral component may be an alternative to a more extensive 

patellar and femoral component revisions. Twenty-three metalbacked 

patellar components were revised. Superficially damaged 

femoral components were retained when a described 

set of criteria were met. At an average follow-up of 80.3 

months, evidence of only one failure (4%) was observed. The 

Knee Society Knee Score improved from 69 to 88 (p



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to be detrimental. High patellofemoral loads are also thought 

to contribute to cartilage deterioration over time. 

Recent prospective, randomized studies favor patellar resurfacing 

over retaining the native patella, reporting increased 

reoperation rates for patellar problems and increased anterior 

knee pain in subjects in which the patella has not been resurfaced. 

These studies also document the reoperation rates to 

convert unresurfaced to resurfaced patellae exceeding those 

for complications after patellar resurfacing. In addition, the 

incidence of residual patellofemoral pain after secondary resurfacing 

is substantially higher than when patellofemoral 

resurfacing is done primarily. Therefore, one cannot be assured 

of an equivalent result (as compared with primary resu-rfacing) 

with secondary patellar resurfacing if substantial patellofemoral 

pain occurs following TKA without initial patellar resurfacing. 

Most studies of subjects in which bilateral TKA has been performed 

with the patella resurfaced in one TKA and nonresurfaced 

in the other have demonstrated patients prefer the TKA 

with the resurfaced patella. Lastly, studies which have analyzed 

intraoperative cartilage condition at the time of TKA have found 

a poor correlation between intraoperative cartilage condition 

and postoperative patellar pain and function, supporting the 

concept that it is difficult to determine who will do well clinically 

without patellar resurfacing based on intraoperative findings. 

Patient selection criteria are critical in the decision-making 

process. Patellofemoral complications, the greatest argument 

against resurfacing, have been diminished with improved surgical 

techniques and implant design. Surgical techniques for 

patellar resurfacing that emphasize a patellar resection that 

reproduces equal facet thickness, native patellar height and 

central patellar tracking, while respecting vascular principles, 

have produced complication rates which range from 0% to 

4%. This is superior to a 10-29% patellofemoral pain incidence 

demonstrated in review of the literature of series without patellar 

resurfacing. If resurfacing is chosen, adherence to proper 

surgical technique principles is imperative as outlined below. 

I. SURGICAL TECHNIQUE GOALS 

A. Preserve the Patellar Tendon 

B. Duplicate Patellar Thickness 

C. Assure Patellar Symmetry 

D. Assure Patellar Tracking 

E. Preserve Patellar Vascularity 

II. PRESERVE THE PATELLAR TENDON 

A. Release Infrapatellar Adhesions 

B. Release Patellofemoral Ligament 

C. Extend Capsulotomy 

D. Externally Rotate Tibia 

E. Secure (Clamp) Tendon Insertion 

III. DUPLICATE PATELLAR THICKNESS 

A. Measure Patellar Thickness 

1. Highly Variable (Average 20-25 mm) 

B. Measure Patellar Component Thickness 

1. Usually 8.5-11 mm 

C. Remove What You’re Replacing 

IV. ASSURE PATELLAR SYMMETRY 

A. Normal Anatomy 

1. Medial Thicker Than Lateral Facet 

B. Minimal Lateral Facet Resection 

1. Typically Flush With Subchondral Bone 

C. Measure Symmetry Post-Resection 

D. Don’t Over-resect To Obtain Flat Surface 

1. Asymmetric Patella ≥ Instability 

2. Lateral Defect ≥ Drill & Fill (PMMA) 

V. ASSURE PATELLAR TRACKING 

A. Surgical Approach 

1. Superior Tracking with Mid-Vastus/Subvastus 

B. Proper Component Positioning 

1. Femoral - Avoid Medial Shift / Internal 

Rotation / Excessive 

Valgus / Femoral Component Flexion 

a. Transepicondylar Axis: Place Parallel To 

b. Anteroposterior Axis: Place Perpendicular To 

2. Tibial - Avoid Medial Shift / Internal Rotation 

3. Patella - Avoid Lateral Shift 

a. Median Crest (High Point) Is 5.42 mm 

(Average) Medial To Midpoint Of Patella 

(Hofmann, et al, J. Arthroplasty, 1997) 

b. Predrill Median Crest - Marker Of Median Crest 

c. Position Highpoint of Dome Over Median Crest 

C. Lateral Retinacular Release / VMO Imbrication If 

Subluxation 

D. Assessment 

1. No Thumb Technique 

2. Assess After Tourniquet Release 

a. Tourniquet Creates Tenodesis Effect 

VI. PRESERVE PATELLAR VASCULARITY 

A. Maintain the Fat Pad 

B. Preserve the Superolateral Geniculate Artery 

1. If Lateral Release Required 

C. Avoid Large Central Lug Component 

1. Disrupts Midpatellar Intraosseus Blood Supply 

VII. PATELLOFEMORAL PROSTHETIC DESIGN 

A. Patellar Component 

1. Dome / Modified Dome Shape – More Forgiving 

2. Three Small Peripheral Fixation Lugs 

a. Less Stress Raiser / Reduced Fracture Risk 

B. Femoral Component 

1. Anatomic Trochlear Groove 

a. Assists Patellar Capture / Reduced Shear 

Stresses (Colwell) 

2. Extended Trochlear Groove 

a. Maximizes Contact Area in Deep Flexion 

REFERENCES 

1. Boyd Jr AD, Ewald FC, Thomas WH, Poss R, Sledge CB: 

Long-term complications after total knee arthroplasty with 

or without resurfacing of the patella. J Bone Joint Surg 

75A: 674-681, 1993.



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2. Burnett RS, Bourne RB: Indications for patellar resurfacing 

in total knee arthroplasty. J Bone Joint Surg 85A: 728- 

745, 2003. 

3. Dennis DA. The role of patellar resurfacing in TKA. Orthopedics. 

29(9):832, 834-5, 2006. 

4. Enis JE, Gardner R, Robledo MA, Latta L, Smith R: Comparison 

of patellar resurfacing versus nonresurfacing in 

bilateral total knee arthroplasty. Clin Orthop 260: 38-42, 

1990. 

5. Forster H, Fisher J: The influence of continuous sliding 

and subsequent surface wear on the friction of articular 

cartilage. Proc Inst Mech Eng 213:329-345, 1999. 

6. Han I, Chang CB, Lee S, Lee MC, Seong SC, Kim TK: 

Correlation of the condition of the patellar articular cartilage 

and patellofemoral symptoms and function in osteoarthritic 

patients undergoing total knee arthroplasty. J Bone Joint 

Surg. Br. 87(8): 1081-4, 2005. 

7. Holt GE, Dennis DA. The role of patellar resurfacing in 

total knee arthroplasty. Clin Orthop Relat Res. 416:76- 

83, 2003. 

8. Kajino A, Yoshino S, Kameyama S, Kohda M, Nagashima 

S: Comparison of the results of bilateral total knee 

arthroplasty with and without patellar replacement for 

rheumatoid arthritis: A follow-up note. J Bone Joint Surg 

Am 79A: 570-574, 1997. 

9. Khatod M, Codsi M, Bierbaum B: Results of resurfacing 

a native patella in patients with a painful total knee 

arthroplasty. J Knee Surg. 17(3): 151-5, 2004. 

10. Nizard RS, Biau D, Porcher R, Ravaud P, Bizot P, 

Hannouche D, Sedel L: A meta-analysis of patellar replacement 

in total knee arthroplasty. Clin Orthop Relat Res. 

432:196-203, 2005. 

11. Pakos EE, Ntzani EE, Trikalinos TA: Patellar resurfacing 

in total knee arthroplasty. A meta-analysis. J Bone Joint 

Surg Am. 87(7): 1438-45, 2005. 

12. Parvizi J, Rapuri VR, Saleh KJ, Kuskowski MA, Sharkey 

PF, Mont MA: Failure to resurface the patella during total 

knee arthroplasty may result in more knee pain and secondary 

surgery. Clin Orthop Relat Res. 438:191-6, 2005. 

13. Waters TS, Bentley G: Patellar resurfacing in total knee 

arthroplasty. A prospective, randomized study. J Bone 

Joint Surg Am. 85-A(2):212-7, 2003. 

TKA WITHOUT PATELLAR COMPONENT 

Leo A. Whiteside, MD 

Missouri Bone and Joint Center 

St. Louis, Missouri, (USA) 

Resurfacing the patella in total knee arthroplasty is commonly 

recommended as the preferred treatment, but other studies 

report superior results of not resurfacing the patella especially 

in qualities of the knee related to quadriceps function such 

as stair climbing. One reason for this discrepancy in the literature 

may be design of the femoral component. Design 

features of the patellofemoral surface have a distinct effect 

on kinematics of the knee, patellar stability, and shear stresses, 

so it would be likely that design features of the femoral 

surface that articulates with the patella also would affect 

postoperative anterior knee pain and revision rates. Various 

femoral component designs have been available during the 

past two decades, and the contact stresses on the unresurfaced 

patella vary greatly among these designs. The 

femoral implants that produced the highest stresses on the 

unresurfaced patella were those with a shallow patellar groove 

and wide intercondylar notch. Those with deeper patellar 

grooves and supporting lateral flange surfaces had low 

contact stress similar to that of the normal patellofemoral 

joint. This suggests that the variation in the reported clinical 

results of not resurfacing the patella could be explained by 

the differences in design features of the femoral component. 

A clinical and laboratory study was done to test the hypothesis 

that reported differences in clinical results of unresurfaced 

patellae in total knee arthroplasty are because of differences 

in design of the femoral component. Thirty-eight knees had 

an Ortholoc II femoral component (shallow patellar groove, 

wide intercondylar notch, and flat femoral surface). Thirteen 

knees had severe and three had moderate anterior knee 

pain. Fifteen required patellar resurfacing later. Two hundred 

twenty-two knees had Advantim femoral components (deepened 

and extended patellar groove, narrow intercondylar 

notch, and rounded femoral surfaces). None of these knees 

had severe anterior knee pain. Eighteen percent had mild 

anterior knee pain on stairs postoperatively. Three hundred 

thirty knees had Profix femoral components (deepened and 

extended patellar groove, rounded femoral surfaces, and 

extended lateral patellar support). Ten percent of Profix 

knees had mild anterior knee pain. This rate was statistically 

signifi-cantly less than that of the knees with Advantim femoral 

components (p



145

Viernes, 11 de abril 

Friday, 11th April 


Prótesis total de rodilla 

Complicaciones 

Rodilla de revisión 

Total knee arthroplasty 

Complications 

Revision knee 

Moderadores / Moderators: Thomas Thornhill, Michael Freeman, 

Jorge Galante, Carlos Resines, Richard “Dickey” Jones

VIERNES / FRIDAY 

148 

08.25 - 14.15 h 


Prótesis total de rodilla / Total knee arthroplasty 

Moderadores: Thomas Thornhill, Michael Freeman, Jorge O. Galante 

THE MOVEMENT OF THE NORMAL TIBIO-FEMORAL JOINT 

M. Freeman a,b,c , V. Pinskerova d 

a Institute of Orthopaedics and Musculoskeletal Science, University College, London (UK) 

b School of Engineering Sciences, Southampton University, Southampton (UK) 

c The Royal London Hospital, London (UK) 

d First Orthopaedic Clinic, Charles University, Prague (Czech Republic)



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TKA KINEMATICS 

Jan Victor 

Assebroek Brugge (Belgium)



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SOFT TISSUE IN TKA, APPROACHES 

AND RELEASES 

Richard “Dickey” Jones, M.D. 

U.T. Southwestern Medical Center. Dallas, Texas (USA) 

The approach goals in TKA are to provide adequate exposure 

for balancing and accurate hard tissue resection. With previous 

incisions always use the most lateral because the vascularity 

of the skin is best in the medial flap. Complex coverage 

problems may require soft tissue expanders or muscle flaps 

pre or post-operatively. Special consideration should be given 

to those patients with rheumatoid arthritis or on steroids and 

excessively obese patients. The extensor mechanism should 

always be protected and preserved. Capsular approach options 

include median parapatellar, subvastus or mid-vastus or lateral 

with tubercle osteotomy. Extensile exposures include the quad 

V-Y, the quad snip, tubercle osteotomy, and extensive proximal 

medial tibial release which allows external rotation and exposure 

without patella eversion. 

We must understand the patient anatomy which produces 

angular deformities about the knee. Flexion extension gaps 

must be balanced and releasing of the concaved deforming 

soft tissue slings assures equal rectangular spaces. Kinematics, 

femoral roll back and condylar rotation must all be evaluated 

intraoperatively. The sequential approach pathway to 

release in TKA requires knowledge of the deforming forces for 

the varus and valgus knee, both in extension and in flexion. 

This will be thoroughly reviewed. There is a definitive correlation 

between alignment and balance in TKA and sys-tem longevity. 

FACTORS AFFECTING FLEXION AFTER 


Douglas A. Dennis, MD 

Adjunct Professor, Department of Biomedical Engineering 

University of Tennessee; Assistant Clinical Professor, 

University of Colorado Health Sciences Center; Director, 

Rocky Mountain Musculoskeletal Research Laboratory 


Numerous factors affect postoperative range of motion following 

total knee arthroplasty (TKA) and can be categorized 

into patient factors, surgical technical errors, alterations in 

knee kinematics, postoperative complications, prosthesis 

design, and postoperative rehabilitations program and effort. 

Factors associated with increased postoperative flexion 

include increased preoperative and intraoperative flexion, 

restoration or posterior femoral condylar offset, increased 

posterior femoral rollback, and the use of posterior cruciate 

substituting TKA designs. 

Factors related to reduced postoperative flexion include preoperative 

flexion contracture, obesity, complications (infection, 

heterotopic ossification, etc.), and reduced pain tolerance 

which can limit rehabilitation effort. Technical errors resulting 

in reduced flexion include errors in component malposition or 

sizing, ligamentous or gap imbalance, overstuffing of the patellofemoral 

joint, and retention of posterior femoral osteophytes. 

The literature is unclear regarding the effect of high flexion 

TKA designs. Fluoroscopic kinematic and flexion evaluation 

of multiple high flexion TKA subjects have demonstrated variable 

results with some exhibiting no increase in flexion while 

others have demonstrated weight-bearing flexion magnitudes 

higher than that observed in standard TKA implants. 

REFERENCES 

1. Dennis DA, Komistek RD, Stiehl JB, Walker SA, Dennis 

KN. Range of motion after total knee arthroplasty: the effect 

of implant design and weight-bearing conditions. J Arthroplasty. 

1998 Oct; 13(7):748-52. 

2. Bellemans J, Banks S, Victor J, Vandenneucker H, Moemans 

A. Fluoroscopic analysis of the kinematics of deep 

flexion in total knee arthroplasty. Influence of posterior condylar 

offset. J Bone Joint Surg Br. 2002 Jan; 84(1):50-3. 

3. Ritter MA, Harty LD, Davis KE, Meding JB, Berend ME. 

Predicting range of motion after total knee arthroplasty. Clustering, 

log-linear regression, and regression tree analysis. 

J Bone Joint Surg Am. 2003 Jul; 85-A(7):1278-85. 

4. Matsuda Y, Ishii Y, Noguchi H, Ishii R. Varus-valgus balance 

and range of movement after total knee arthroplasty. J Bone 

Joint Surg Br. 2005 Jun;87(6):804-8. 

5. Kurosaka M, Yoshiya S, Mizuno K, Yamamoto T. Maximizing 

flexion after total knee arthroplasty: the need and the pitfalls. 

J. Arthroplasty. 2002 Jun;17(4 Suppl 1):59-62. 

6. Dennis DA, Komistek RD, Scuderi GR, Zingde S. Factors 

affecting flexion after total knee arthroplasty. Clin Orthop 

Relat Res. 2007;464:53-60. 

THE IMPACT OF LIGAMENT BALANCING 

IN TOTAL KNEE ARTHROPLASTY 

José Romero, M.D. 

Endoclinic Zurich, Center for Arthroplasty and Joint Surgery, 

Klinik Hirslanden, Switzerland 

Symmetrically balanced collateral soft tissues in extension 

and in flexion 1,2 and alignment of the tibial and femoral 

components perpendicular to the mechanical axis in the 

coronal plane 3 are major surgical goals in total knee arthroplasty. 

Erroneous resection of the tibial plateau and distal 

femoral condyles or inadequate soft tissue release for varus



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or valgus contracture will result in an asymmetric extension 

gap. Extension gap imbalance due to insufficient soft tissue 

release may cause polyethylene edge overload 4 and consequently 

accentuated wear 5 . Overrelease of the collateral 

structures may result in symptomatic instability 6 . Mild to moderate 

increased varus-valgus laxity in extension has been 

reported to be of no clinical importance 7 . However, major 

instability may be an important cause for total knee arthroplasty 

failure 8 and accounted for 21% of 212 revision total knee 

arthroplasties in the series by Sharkey et al. 9 . Fehring et al. 10 

reported on 27% instability cases in their total knee revision 

population of 440 patients who had to be revised after a 

follow-up of less than 5 years after primary TKA. 

Increased varus or valgus laxity in flexion due to femoral 

component malrotation has extensively been examined in 

cadaveric studies under loaded 11 and unloaded conditions12. 

Although femoral component malrotation is considered the 

major cause for flexion gap imbalance 12,13 little is known on 

the clinical consequences. Laskin 14 reported on patients with 

medial tibial pain if the femoral component was not externally 

rotated to allow rectangularization of the flexion gap. Varus 

and valgus laxity in flexion might be difficult to quantify by 

clinical examination. In a cadaver study, Grood et al. 15 compared 

manually assessed medial and lateral joint opening 

with varus and valgus laxity determined by means of an Instron 

testing system. They proved that erroneous laxity assessment 

in flexion is likely to occur by clinical examination even 

when the primary restraint is missing and the testing system 

demonstrates a large joint opening. The application of fluoroscopic 

stress radiography on a patient lying relaxed on a 

designated radiolucent bench is a feasible, inexpensive, fast, 

safe, and reproducible method for detecting increased varusvalgus 

laxity of the knee in flexion on a routine base 16 . The 

moment applied to the tibia has to be pain free avoiding quadriceps 

and hamstrings cocontraction, which increases tibiofemoral 

joint reaction force and decreases joint opening 17 . 

A recent study using a three-dimensional interactive modelfitting 

technique for two-dimensional fluoroscopic dynamic 

images confirms that increased femorotibial separation 

(“condylar lift-off”) under weight-bearing conditions in flexion 

was more pronounced on the lateral side, and was associated 

with femoral component malrotation 18 . A study by Stiehl et 

al. confirms that condylar lift-off occurs in clinically successful 

total knee replacements 19 , but it is not known to what extend 

this condition may be clinically tolerated. An exaggerated 

condylar-lift off due to increased lateral flexion laxity because 

of a malrotated femoral component may disturb knee kinematics 

and ultimately accentuate edge loading, which has 

been implicated as a cause of premature polyethylene failure 

20 . A study using the WOMAC score as clinical outcome 

measurement revealed that there are specific symptoms 

associated with increased flexion gap imbalance due to 

internal femoral component malrotation 21 . The predominant 

patient complaints were pain on stair climbing, reduced function 

on descending stairs and rising from a chair, and difficulties 

getting in and out of a car or getting in and out of bath. Attfield 

et al. 22 reported also on knees which were not balanced in 

flexion but fully balanced in extension. Proprioception was 

reduced in such knees compared to knees which were properly 

balanced in flexion and extension. 

An important goal during surgery must be a well balanced 

knee not only in extension but also in flexion. Proper femoral 

component rotation reduces flexion gap imbalance. A tensor 

may help intraoperatively to set the patients appropriate femoral 

component rotation which results in a rectangular 

flexion gap based on ligament tension in flexion after having 

performed the ligament balancing in extension first. 

BIBLIOGRAPHY 

1. Freeman MAR: Anonymous Arthritis of the knee: Clinical 

features and surgical management. Springer-Verlag, 

New York, 1980 

2. Insall JN: Choices and compromises in total knee arthroplasty. 

Clin Orthop 226:43, 1988 

3. Insall JN: Surgical techniques and instrumentation in total 

knee arthroplasty. In Insall JN, Windsor RE, Kelly MA, 

Scott WN, Aglietti P (eds): Surgery of the knee. Churchill 

Livingstone, New York, Edinburgh, London, Madrid, Melbourne, 

Tokyo, 1993, pp. 739. 

4. Hsu RWW, Himeno S, Coventry MB, Chao EYS: Normal 

axial alignment of the lower extremity and load-bearing 

distribution at the knee. Clin Orthop 255:215, 1990 

5. Wasielewski RC, Galante JO, Leighty RM, Natarajan 

RN, Rosenberg AG: Wear patterns on retrieved polyethylene 

tibial inserts and their relationship to technical 

considerations during total knee arthroplasty. Clin Orthop 

299:31, 1994 

6. Griffin WL: Prosthetic knee instability: prevention and treatment. 

Current Opinion in Orthopaedics 12:37, 2001 

7. Edwards E, Miller J, Chan KH: The effect of postoperative 

collateral ligament laxity in total knee arthroplasty. Clin 

Orthop 236:44, 1988 

8. Mitts K, Muldon MP, Gladden M, Padgett DE: Instability 

after total knee arthroplasty with the Miller Gallante II total 

knee - 5-7 years follow-up. J Arthroplasty 16:422, 2001 

9. Sharkey PF, Hozack WJ, Rothman RH, Shastri S, Jacoby 

SM: Why are total knee arthroplasty failing today. Clin 

Orthop 404:7, 2002 

10. Fehring TK, Odum S, Griffin WL, Mason JB, Nadaud M: 

Early Failures in Total Knee Arthroplasty. Clin Orthop 

392:315, 2001 

10. Romero J, Duronio JF, Sohrabi A, et al: Varus and valgus 

flexion laxity of total knee alignment methods in loaded 

cadaveric Knees. Clin Orthop 394:243, 2002 

11. Anouchi YS, Whiteside LA, Kaiser AD, Milliano MT: The 

effects of axial rotational alignment of the femoral component 

on knee stability and patellar tracking in total knee 

arthroplasty demonstrated on autopsy specimens. Clin 

Orthop 287:170, 1993 

12. Fehring TK: Rotational malalignment of the femoral component 

in total knee arthroplasty. Clin Orthop 380:72, 

2000



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13. Laskin RS: Flexion space configuration in total knee 

arthroplasty. J Arthroplasty 10:657, 1995 

14. Grood ES, Stowers SF, Noyes FR: Limits of movement 

in the human knee. J Bone Joint Surg 70-A: 88, 1988 

15. Stähelin T, Kessler O, Pfirrmann C, Jacob HAC, Romero 

J: Fluoroscopically assisted stress radiography for varusvalgus 

assessment in flexion after total knee arthroplasty. 

J Arthroplasty 18:513, 2003 

16. Mac Williams BA, Wilson DR, Des Jardins JD, Romero 

J, Chao EYS: Hamstrings cocontraction reduces internal 

rotation, anterior translation, and anterior cruciate ligament 

load in weight-bearing flexion. J Orthop Res 17:817, 1999 

17. Insall JN, Scuderi GR, Komistek RD, Math K, Dennis DA, 

Anderson DT: Correlation between condylar lift-off and 

femoral component alignment. Clin Orthop 403:143, 2002 

18. Stiehl JB, Dennis DA, Komistek RD, Crane HS: In vivo 

determination of condylar lift-off and screw-home in a 

mobile-bearing total knee arthroplasty. J Arthroplasty 

14:293, 1999 

19. Lewis P, Rorabeck CH, Bourne RB, Devane P: Posteromedial 

tibial polyethylene failure in total knee replacements. 

Clin Orthop 299:11, 1994 

20. Romero J., Stähelin T., Binkert C., Pfirrmann C.W., Hodler 

J., Kessler O.: The clinical consequences of flexion gap 

asymmetry in total knee arthroplasty. J Arthroplasty 22 

(2):235-40, Feb 2007 

21. Attfield SF, Wilton TJ, Pratt DJ, Sambatakakis A: Softtissue 

balance and recovery of proprioception after total 

knee replacement. J Bone Joint Surg 78-B:540, 1996 

MEASURED RESECTION VERSUS GAP 

BALANCING TECHNIQUE 

Douglas A. Dennis, M.D 

Adjunct Professor, Dept. of Biomedical Engineering, University 

of Tennessee; Assistant Clinical Professor, University of 

Colorado Health Sciences Center; Clinical Director, Rocky 

Mountain Musculoskeletal Research Laboratory 


Controversy persists regarding the most favourable method 

to determine accurate femoral component rotation during 

total knee arthroplasty (TKA). Some favour a measured resection 

technique in which bone landmarks (femoral epicondyles, 

posterior femoral condyles, or the anteroposterior 

axis) are the primary determinants of femoral component 

rotation. Others recommend a gap balancing methodology 

in which the femoral component is positioned parallel to the 

resected tibia with each collateral ligament equally tensioned. 

Recent research has documented that accurate surgeon 

identification of bone landmarks is frequently NOT obtained 

which can result in flexion gap asymmetry. To test this hypo- 

thesis, two hundred twelve patients underwent a total knee 

arthroplasty utilizing a computer navigation system (Ci Navigation 

System; Depuy, Warsaw, IN). The transepicondylar, 

anteroposterior, and the posterior condylar axes were registered. 

CAS optimized femoral rotation (gap balancing) was 

then compared to use of the anatomic bony landmarks to 

evaluate the accuracy of these landmarks in determining rotation 

of the femoral component. Comparing the gap balancing 

method to the anatomic landmarks, use of the epicondylar 

axis for determination of femoral component rotation was 

a mean 0.9º externally rotated (range, 12º internal to 16º external), 

with the flexion gap balanced (+/- 3º) 43% of the 

time. The posterior condylar axis was a mean of 0.4º internally 

rotated (range, 15º internal, 13º external), with the flexion gap 

balanced 58% of the time. The anteroposterior axis was a 

mean of 1.9º externally rotated (range 13º internal, 18º external), 

with the flexion gap balanced 39% of the time. 

An additional fluoroscopic analysis of TKA performed utilizing 

either measured resection vs. gap balancing methods demonstrated 

a significantly lower incidence of femoral condylar 

lift-off when a gap balancing technique was used, further 

confirming the superiority of use of the gap balancing technique 

in obtaining a balanced flexion gap. 

CONCLUSION 

Surgeons have been shown to be inaccurate in locating the 

anatomic landmarks recommended for femoral component 

rotation. When anatomic landmarks were used to determine 

femoral component rotation, an asymmetric, trapezoidal flexion 

gap was frequently observed with an increased incidence 

of femoral component lift-off. Rotation of the femoral component 

using a gap balancing technique results in better gap 

symmetry, which should create more favourable knee kinematic 

patterns and reduced polyethylene wear. 

REFERENCES 

1. Fehring TK. Rotational malalignment of the femoral component 

in total knee arthroplasty. Clin Orthop Relat Res. 

2000;Nov(380):72-9. 

2. Poilvache PL, Insall JN, Scuderi GR, Font-Rodriguez DE. 

Rotational landmarks and sizing of the distal femur in total 

knee arthroplasty. Clin Orthop Relat Res. 1996;Oct(331):35- 

46. 

3. Whiteside LA, Arima J. The anteroposterior axis for femoral 

rotation alignment in valgus total knee arthroplasty. Clin 

Orthop Relat Res. 1995;Dec(321):168-72.



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LIGAMENT BALANCING IN 

THE VARUS KNEE 


Missouri Bone and Joint Research 

Foundation Missouri Bone and Joint Center 

St. Louis, Missouri (USA) 

Medial stability of the knee is a complex issue, and involves 

ligaments that behave differently in flexion and extension. 

The contracture and stretching that occur due to deformity 

and osteophytes affect these ligament structures unequally, 

and often cause different degrees of tightness or laxity in flexion 

and extension after the bone surfaces are resected correctly 

for varus-valgus alignment. The distortion of alignment 

landmarks also can cause varus-valgus alignment to differ 

in the flexed and extended positions, and the knee thus may 

require adjustment of portions of the medial stabilizing complex 

that affects stability either in flexion or extension. 

The cornerstone to correct ligament balancing is correct varus 

and valgus alignment in flexion and extension. For alignment 

in the extended position, fixed anatomic landmarks such as 

the intramedullary canal of the femur and long axis of the tibia 

are accepted. When the joint surface is resected at an angle 

of 5° to 7° valgus to the medullary canal of the femur and perpendicular 

to the long axis of the tibia, the joint surfaces are 

perpendicular to the mechanical axis of the lower extremity, 

and roughly parallel to the epicondylar axis. In the flexed position, 

anatomic landmarks are equally important for varus-valgus 

alignment. Incorrect varus-valgus alignment in flexion not only 

malaligns the long axes of the femur and tibia, but also incorrectly 

positions the patellar groove both in flexion and extension. 

Finding suitable landmarks for varus-valgus alignment has 

led to efforts to use the posterior femoral condyles, epicondylar 

axis, and anteroposterior (AP) axis of the femur. The posterior 

femoral condyles provide excellent rotational alignment landmarks 

if the femoral joint surface has not been worn or otherwise 

distorted by developmental abnormalities or the arthritic 

process. However, as with the distal surfaces, the posterior 

femoral condylar surfaces sometimes are damaged or hypoplastic 

(more commonly in the valgus than in the varus knee) 

and cannot serve as reliable anatomic guides for alignment. 

The epicondylar axis is anatomically inconsistent and in all 

cases other than revision total knee arthroplasty with severe 

bone loss, is unreliable for varus-valgus alignment in flexion 

just as it is in extension. The AP axis, defined by the lateral 

border of the posterior cruciate ligament posteriorly and the 

deepest part of the patellar groove anteriorly, is highly 

consistent, and always lies within the median sagittal plane 

that bisects the lower extremity, passing through the hip, knee, 

and ankle. When the articular surfaces are resected perpendicular 

to the AP axis, they are perpendicular to the AP plane, 

and the extremity can function normally in this plane throughout 

the arc of flexion. 

In the presence of articular surface deformity the anatomic 

refe-rences are especially important for correct varus-valgus 

alignment. The usual reliable landmarks for varus-valgus 

alignment of the femoral component in flexion include the 

posterior femoral condyles, the long axis of the tibia, and the 

tensed supporting ligaments. If the posterior femoral condylar 

wears and the tibial plateau collapses on the medial side of 

the knee, these normally reliable landmarks cannot be used. 

Instead, the AP axis of the femur is used as a reference line 

for the femoral cuts and the long axis of the tibia is used for 

a reference line for the tibial cut so that the joint surfaces 

are cut perpendicular to these two reference lines. Once the 

joint surfaces have been resected correctly to establish normal 

varus-valgus alignment in flexion and extension, the trial 

components are inserted and ligament function is assessed 

in flexion and extension. The ligaments are released according 

to their function at each position. The medial collateral ligament 

(deep and superficial layers) attaches to the medial 

epicondylar area through a broad band. The posterior oblique 

portion, which spreads posteriorly over the medial tibial flare 

and incorporates the sheath of the semimembranosus tendon, 

tightens in extension. The anterior portion of the ligament complex, 

which extends anteriorly along the medial tibial flare, 

tightens in flexion and loosens in extension. The posterior 

capsule is loose in flexion, and tightens only in full extension. 

With this information the medial ligament structures of the 

knee can be released individually according to the position 

in which excessive tightness is found. 

The sequence in which the procedures are performed is important 

in total knee replacement. Resection of the femoral 

surfaces makes the tibial surfaces accessible. Resection of 

the tibial surface clears the way to remove the osteophytes. 

Removal of the osteophytes frees the ligaments so they may 

be assessed and released as needed. No ligament should 

be released until all the osteophytes are removed otherwise 

excessive laxity may occur. Extra bone should not be removed 

to correct a flexion contracture until all ligament balancing 

has been finished, otherwise inappropriate laxity in extension 

may occur with ligament release. 

The trial components are inserted before any ligament releases 

are done, and the knee is tested for stability in flexion 

and extension. With the trials in place, the knee is evaluated 

in flexion and extension to assess varus, valgus, rotational, 

anterior and posterior stability. Once the surgeon has determined 

with certainty which ligaments are contracted, limited 

releases can be done, releasing only the ligaments that are 

tight and leaving alone those that are not. 

TIGHT MEDIALLY IN FLEXION, LOOSE MEDIALLY IN EXTENSION 

In some cases the medial structures are not contracted uniformly, 

and the knee may be tight medially only in flexion, but 

not in extension. The anterior portion of the medial collateral



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ligament should be released first. This leaves the posterior 

oblique portion intact to provide stability both in flexion and 

extension. 

TIGHT IN EXTENSION, BALANCED IN FLEXION 

In some cases the posterior medial structures are tight and 

the anterior MCL is normal after insertion of the trial components. 

These knees are tight in extension, but balanced normally in 

flexion. Knees that are tight only in extension after total knee 

arthroplasty first should have release of the posterior oblique 

fibers of the MCL, and release of the posterior capsule if medial 

contracture persists in extension. This procedure leaves 

the anterior portion of the MCL intact to stabilize the knee. 

TIGHT MEDIALLY IN FLEXION AND EXTENSION 

In many cases with a long-standing varus deformity and 

medial ligament contracture, the knee is tight medially both 

in flexion and extension. This indicates that the entire MCL 

is contracted. The posterior capsule and PCL also may be 

contracted, but the primary contracture is the MCL in these 

cases. The PCL and posterior capsule cannot be evaluated 

until the MCL contracture has been corrected. Knees that 

are tight in flexion and extension have release of the anterior 

and posterior portions of the medial collateral ligament. This 

is done by first stripping the anterior portion of the MCL in 

line with the tibial long axis, then directing the osteotome 

posteriorly to release the posterior portion of the ligament. 

Those knees that remain tight in full extension after release 

of the posterior oblique MCL have release of the posterior 

medial capsule from the femur and tibia. If inappropriate posterior 

femoral rollback occurs, or if medial ligament tightness 

remains in flexion after release of the anterior portion of the 

MCL, the PCL is released from its tibial attachment. 

TIGHT POPLITEUS TENDON 

Occasionally the popliteus tendon and its surrounding structures 

are tight in the varus knee after the medial side has been 

corrected. This often is difficult to detect, but rotational stability 

testing of the tibia demonstrates that the tibia is held anteriorly 

on the lateral side and pivots around the lateral edge of the 

tibial component. The popliteus tendon is released from its 

bone attachment when the knee is flexed. It is found just distal 

and posterior to the lateral collateral ligament (LCL) attachment, 

and care must be taken to avoid release of the LCL 

during this procedure. 

COMPENSATORY LATERAL RELEASEEXTENSION ONLY 

Occasionally, after full MCL release, the knee is excessively 

loose on the medial side in extension, and tight laterally. 

Compensatory lateral release corrects the imbalance, and 

a thicker tibial component brings the knee to correct stability. 

COMPENSATORY LATERAL RELEASEFLEXION AND 

EXTENSION 

In some cases after full release of the MCL, the secondary 

stabilizers are inadequate to provide medial stability in flexion 

and extension, and the knee is too loose medially after the 

tibial component has been sized to bring the lateral ligaments 

to their normal tension. In those cases the LCL and popliteus 

tendon are released to create more laxity both in flexion and 

extension, and a thicker tibial component is used to tension 

the medial structures. 

MEDIAL PIVOT KNEE ARTHROPLASTY 

J. David Blaha, M.D. 

University of Michigan. Medical School, 

(USA) 

Design of total knee prostheses is predicated on knowledge 

of the kinematics of the normal knee. Designs that more closely 

mimic the normal might reasonably be expected to perform 

more normally for the patient. For many years the knee joint 

has been viewed as a “four-bar link” in which the ligaments 

(specifically the cruciate ligaments) guide the motion of the knee 

in such a way that “rollback” occurs. (Rollback is the progressive 

posterior movement of the contact point between the femur 

and the tibia with increasing flexion.) Proponents of the fourbar 

link model point to studies that have shown a decreasing 

radius of curvature of the femoral condyles from distal to posterior. 

Several recent studies of knee joint kinematics have suggested 

that the knee can be modeled as having a single axis of flexion-extension. 

Similarly, the internal and external rotation of 

the tibia around the femur (i.e., the pivot) of the knee can be 

modeled by an axis roughly at the central part of the medial 

condyle. (van Dijk et al. 1983, Blankevoort et al. 1988, Hollister 

et al. 1993, Mancinelli et al. 1994, Blaha et al. 2003) These 

studies show that the normal knee does not roll-back, but 

rather remains remarkably constant in position on the medial 

side (like a ball in a socket) while varying in contact position 

on the lateral side to accommodate internal and external 

rotation of the tibia about the femur. 

Kinematic studies of total knee prostheses designed respecting 

the concept of the “four-bar link” and providing for roll back 

have demonstrated paradoxical kinematics. Instead of rolling 

back, these knees demonstrate sliding forward of the femur 

on the tibia during in vivo fluoroscopic studies. A similar kinematic 

study done with a knee joint designed for medial pivot and 

medial ball-in-socket kinematics does not demonstrate paradoxical 

motion. (Banks et al. 1997, Dennis et al 1997, Blaha et 

al. 1998) 

The Advance® Medial-Pivot (Wright Medical Technology, Arlington 

TN USA) total knee prosthesis has been in clinical use 

for 5 years (as of January, 2003). Based on the preliminary results 

available at the time of the writing of this abstract the medial 

ball-in-socket configuration of the implant appears to provide 

a clinical result characterized by enhanced anterior-posterior 

stability both to clinical examination and in functional use.



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190 

LIGAMENT BALANCING IN 

THE VALGUS KNEE 


Missouri Bone and Joint Center St. Louis, 

Missouri, (USA) 

The cornerstone to correct ligament balancing is correct varus 

and valgus alignment in flexion and extension. For alignment 

in the extended position, fixed anatomic landmarks such 

as the intramedullary canal of the femur and long axis of the 

tibia are accepted. When the joint surface is resected at an 

angle of 5° to 7° valgus to the medullary canal of the femur 

and perpendicular to the long axis of the tibia, the joint surfaces 

are perpendicular to the mechanical axis of the lower extremity, 

and roughly parallel to the epicondylar axis. In the flexed position, 

anatomic landmarks are equally important for varusvalgus 

alignment. Incorrect varus-valgus alignment in flexion 

not only malaligns the long axes of the femur and tibia, but 

also incorrectly positions the patellar groove both in flexion 

and extension. 

Finding suitable landmarks for varus-valgus alignment has 

led to efforts to use the posterior femoral condyles, epicondylar 

axis, and anteroposterior (AP) axis of the femur. The posterior 

femoral condyles provide excellent rotational alignment 

landmarks if the femoral joint surface has not been worn or 

otherwise distorted by developmental abnormalities or the 

arthritic process. However, as with the distal surfaces, the 

posterior femoral condylar surfaces sometimes are damaged 

or hypoplastic (more commonly in the valgus than in the varus 

knee) and cannot serve as reliable anatomic guides for alignment. 

The epicondylar axis is anatomically inconsistent and 

in all cases other than revision total knee arthroplasty with 

severe bone loss, is unreliable for varus-valgus alignment in 

flexion just as it is in extension. The AP axis, defined by the 

lateral border of the posterior cruciate ligament posteriorly 

and the deepest part of the patellar groove anteriorly, is highly 

consistent, and always lies within the median sagittal plane 

that bisects the lower extremity, passing through the hip, 

knee, and ankle. When the articular surfaces are resected 

perpendicular to the AP axis, they are perpendicular to the 

AP plane, and the extremity can function normally in this plane 

throughout the arc of flexion. 

In the valgus knee with significant posterior deformity or erosion, 

the posterior femoral condyles are unreliable as rotational 

alignment landmarks, and the anteroposterior axis provides 

a reliable landmark for rotational alignment of the femoral 

surface cuts. 

TECHNIQUE FOR FEMORAL BONE RESECTION 

Intramedullary alignment instruments usually are used for 

the femoral resection. The distal femoral surfaces are resected 

at a valgus angle of 5-7°. A medialized entry point generally 

is advised because the distal femur curves toward valgus in 

the valgus knee. The current technique is to reference the 

resection from the distal medial femoral surface. The distal 

femoral cutting guide is seated on the distal surface of the 

medial femoral condyle, which is resected equal to the 

thickness of the distal condylar surface of the implant. If the 

distal lateral femoral condylar surface is deficient, considerably 

less is resected from the lateral surface than from the medial 

surface, and in many cases of a severe valgus angle, no 

bone is present to resect from the distal lateral surface. Seating 

on bone is necessary on the lateral distal side, but this 

can be accomplished with the anterior lateral bevel surface. 

In cases of severely deficient lateral femoral condylar bone 

stock, the anterior bevel surface is the only bony contact for 

the distal lateral surface of the femoral component. This 

leaves a gap that is filled with bone graft between the distal 

bone surface and the inner surface of the implant on the 

lateral side. When the posterior flange and the anterior bevel 

surfaces are seated on viable bone, the distal defect can be 

treated as a contained defect and needs no structural grafting. 

Rotational alignment of the distal femoral cutting guide is 

adjusted to resect the anterior and posterior surfaces perpendicular 

to the anteroposterior axis of the femur. The AP axis 

is drawn and the femoral cutting guides are aligned to make 

the cuts perpendicular to this line. In the valgus knee this almost 

always results in much greater posteromedial than 

posterolateral femoral condylar resection. 

TECHNIQUE FOR TIBIAL BONE RESECTION 

Intramedullary alignment instruments are used to resect the 

proximal tibial surface perpendicular to its long axis. Like the 

femoral resection, resection of the proximal tibial surface is 

based on the height of the intact medial bone surface. A maximum 

thickness of 10 mm is removed from the medial tibial 

plateau, which often leaves the defect on the lateral side of 

the tibia that requires a bone graft. Use of a long-stem tibial 

component and screws in the tibial tray securely fixes the tibial 

component, and obviates the use of fixed structural bone graft. 

LIGAMENT RELEASE TECHNIQUE AND DIFFERENTIAL 

BALANCING 

Stability is assessed first in flexion by holding the knee at 90° 

flexion and maximally internally rotating the extremity to stress 

the medial side of the knee, then maximally externally rotating 

the extremity to evaluate the lateral side of the knee. A medial 

opening greater than 4 mm, and a lateral opening greater than 

5 mm, is considered abnormally lax, whereas an opening less 

than 2 mm on either side is considered abnormally tight. The 

knee then is extended and stability is assessed in full extension 

by applying varus and valgus stress to the knees. A medial 

opening greater than 2 mm and a lateral opening greater 

than 3mm is considered abnormally lax, whereas an opening 

less than 1 mm on either side is considered abnormally tight. 

TIGHT LATERALLY IN FLEXION ONLY 

In knees that are too tight laterally in flexion, but not in extension, 

the LCL is released in continuity with the periosteum



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and synovial attachments to the bone. When this lateral 

tightness is associated with internal rotational contracture, the 

popliteus tendon attachment to the femur also is released. 

The iliotibial band and lateral posterior capsule should not be 

released in this situation because they provide lateral stability 

only in extension. 

TIGHT LATERALLY IN FLEXION AND EXTENSION 

The only structures that provide passive stability in flexion are 

the LCL and the popliteus tendon complex, so knees that are 

tight laterally in flexion and extension have popliteus tendon 

or LCL release (or both). Stability is tested after adjusting tibial 

thickness to restore ligament tightness on the lateral side of 

the knee. Additional releases are done only as necessary to 

achieve ligament balance. Any remaining lateral ligament 

tightness usually occurs in the extended position only, and is 

addressed by releasing the iliotibial band first, then the lateral 

posterior capsule if needed. The iliotibial band is approached 

subcutaneously and released extrasynovially, leaving its 

proximal and distal ends attached to the synovial membrane. 

TIGHT LATERALLY IN EXTENSION ONLY 

In knees that initially are too tight laterally in extension, but 

not in flexion, the LCL and popliteus tendon are left intact, 

and the iliotibial band is released. If this does not loosen the 

knee enough laterally, the lateral posterior capsule is released. 

The LCL and popliteus tendon rarely, if ever, are released in 

this type of knee. 

Finally, the tibial component thickness is adjusted to achieve 

proper balance between the medial and lateral sides of the 

knee. Anteroposterior stability and femoral rollback are assessed, 

and posterior cruciate substitution is done if necessary 

to achieve acceptable posterior stability. 

LONG TERM CLINICAL EXPERIENCE WITH 

CRUCIATE RETAINING TKA 

Jorge O. Galante, MD. 

Rush Arthritis & Orthopaedic Institute St. Luke’s Medical 

Center. Illinois (USA) 

Design rationale in PCL retaining devices should include: 

asymmetric femoral condyles, ability to reproduce the AP 

dimensions of the femur, relatively flat unconstrained tibial 

articulating surfaces, and a slope of 7 degrees on the tibial 

cut. Preservation of bone stock is possible both in the femur 

and in the tibia. The use of four small pegs in the tibial component 

instead of a stem allows for limited intrusion on the 

upper end of the tibia. 

A critical issue is the tension in the posterior cruciate ligament, 

a function of prosthetic design as outlined above and surgical 

technique. We recommend the use of measured resection 

technique and instrumentation. The possibility of restoring 

the AP dimensions of the femur within 1 mm. makes restoration 

of the flexion gap an easy task. In more contemporary designs, 

improved kinematics at the patellofemoral joint and high 

flexion designs provide additional valuable features to minimize 

patellofemoral complications and improve the range of motion. 

We have reported excellent long term results our first and 

second generation designs. Our experience showed excellent 

fixation with no loosening and no osteolysis at 15 years. Late 

instability was not a problem. 

We evaluated implant survivorship, reoperation rates, and 

complication rates of a group of patients who had total knee 

arthroplasty with a third-generation cemented cruciate-retaining 

design at 10 to 12 years follow up. 

One hundred and eighty six consecutive primary total knee 

arthroplasties were performed at our institution during a 2year 

period. Kaplan Meier survivorship using revision for any 

reason as endpoint was 98% at 10 years. Three patients required 

revision. One for deep infection, one for a periprosthetic 

fracture and one for arthrofibrosis. No patients had reoperation 

for problems related to the patellofemoral joint. Our results 

show that with appropriate patient selection and meticulous 

attention to surgical technique, excellent clinical and radiographic 

results can be achieved. 

The high prevalence of patellofemoral complications with the 

original design was obviated by changes in the shape of the 

patellofemoral articulation. 

Cruciate retaining designs can provide excellent long-term 

function when the appropriate design and surgical technique 

are used. 

FEMORAL COMPONENT POSITIONING IN 

TKA. A 3-D PROBLEM 

J. David Blaha, Ann Arbor 

University of Michigan Medial School, 

Michigan (USA) 

Placing total knee components in the proper position in all 

three planes (frontal, sagittal and transverse) is important for 

correct functioning of the arthroplasty. Until relatively recently 

little attention has been paid to positioning in the transverse 

plane – often referred to as the “rotational” position of components. 

There has been acceptance of the transepicondylar 

axis (TEA) is a landmark by which the surgeon can align the 

femoral component of a total knee replacement to achieve 

proper rotation. Surgeons have experienced problems, however, 

finding the epicondyles with certainty making this set 

of landmarks difficult to use, and there is some concern that 

the epicondyles do not always define a kinematically proper 

placement. A line down the trochlear groove (AP axis – most



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often attributed to Whiteside) has been suggested as another 

guide to proper rotational position. 

In fact, the proper placement for a total knee prosthesis is 

such that the axis of flexion of the component (i.e., the flexionextension 

axis) is collinear with a functionally appropriate 

flexion axis for the patient’s knee. Kinematic work with cadaver 

limbs has been used to find a functionally appropriate flexion 

axis for the knee. As a first approximation appropriate for 

total joint prosthesis design, the knee joint moves in a plane 

perpendicular to this flexion-extension axis. A plane perpendicular 

to the appropriate flexion axis is not coincident with 

either the anatomic axis (i.e., shafts of the bones) or the 

classically described mechanical axis (i.e., femoral head– 

center knee–center ankle). Rather, when the plane is constructed 

through the trochlear groove, it intersects four functional 

points: the lateral border of the acetabulum (origin of the 

rectus femoris muscle), the trochlear groove, the tibial tubercle 

and the neck of the talus. If the plane is moved in a medial 

direction so that it passes through the center of rotation of 

the hip, it passes through the center of the medial condyle 

of the femur. Thus we can define a functional axis (through 

the trochlear groove) or a slightly altered mechanical axis, 

which we will call the kinematic mechanical axis, through the 

hip and the medial side of the knee. 

If a prosthesis has a decreasing radius of curvature (as many 

older and current designs do) then the laxity provided allows 

anterior posterior motion of the femur on the tibia and the 

kinematic effect of slight malplacement of the components 

does not lead to decreased range of motion. However, the 

lack of anterior-posterior conformity does lead to AP instability. 

Such AP instability may not be noticed by older, less high 

demand patients. Younger and higher demand patients sense 

this instability and prefer AP stable joints. It thus becomes 

critical to place conforming joints in the kinematically correct 

position so that the arthroplasty will function with satisfactory 

range of motion and stability. 

The AP clamp attaches to the femur at the most posteriorsuperior 

part of the intercondylar notch with an acutely curved 

portion and to the trochlear groove with a more gently curved 

portion. When used with an appropriately angled intramedullary 

rod the AP clamp establishes the plane perpendicular 

to which a total knee femoral prosthesis should be placed. 

POST-CAM BEHAVIOUR IN PS-TKA 


Head department of Orthopaedics AZ Nikolaas 

Hospital St Niklaas (Belgium) 

Every PS –TKP has some sort of post-cam mechanism 

First PS-TKP was implanted in 1978 by Insall! 

The argument for this posterior cruciate ligament-substituting 

prosthesis was to improve: 

- joint stability. 

- range of motion 

- ability to climb stairs 

Nowadays many surgeons prefer Posterior Cruciate Ligament 

sacrificing devices. 

They argue that it prevents posterior subluxation of the tibia, 

act as a replacement for the PCL and forces roll-back. 

Why and when do I use a PCL sacrificing device? 

• In deformities >15° 

• In RA 

• After prior HTO 

• After patellectomy 

• To avoid aberrant kinematics as in PCL retaining knees. 

• To allow for more natural kinematics or a guided motion 

pattern. 

Therefore we need a posterior cruciate ligament-substituting 

mechanism. There are 2 types: 

• Transverse cam on the femoral component + a central 

polyethylene post on the tibial component. 

• Dished polyethylene insert with a raised anterior lip. 

The post-cam is a potential source of poly damage and wear 

debris 

Contact stress occurs at the post-cam mechanism. 

Different wear patterns are caused by different designs 

Posterior stabilised cam designs: 

• In the saggital plane many cams are oval-shaped ,but 

the direction of the cam apex differs: 

1. Oriented distally 

2. Oriented posteriorly. 

3. Oriented postero-distally. 

• In the axial plane we have 2 groups of design : 

1. Flat-on-flat design. 

2. Curved-on-curved design. 

The effect of tibial rotation on the post-cam mechanism 

• Very high contact stress for all fixed-bearings. 

• The flat post-cam design demonstrated the greatest 

increase in stress due to edge loading. 

The mobile bearing prevents increased contact stress during 

tibial rotation. 

RESULTS OF THE STUDY WILL BE PRESENTED 

Conclusion. In The PS-MB the Mobile Bearing design avoids 

wear of the polyethylene post! 

GEOMETRY ROM AND WEAR: RELATIONSHIP 


Professor Biomechanics. 

The Hospital for Special Surgery (USA) 

One of the major goals of total knee joint arthroplasty is to 

provide the patient with the opportunity of returning to a full, 

active range of motion. Historically that has not always been 

an objective, as the first generation of knee prostheses provided 

only approximately 95 degrees of knee flexion. Modern



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knee designs have as a goal the restoration of knee motion 

to the maximum achievable by each patient. Those patients 

who can achieve motion greater than 135 degrees can benefit 

from the “ high flexion” knees. The key to obtaining optimum 

knee flexion is designing the articular surface geometry so 

that femoral roll back is achieved with either a retained posterior 

cruciate ligament or a ligament substituting cam mechanism. 

Optimization of the articular surface position is more critical 

for the retained cruciate design. Once the anterior/posterior 

curvature of the articular surface and its location is optimized, 

the knee joint’s wear rate may be minimized by choosing appropriate 

medial/lateral radii of curvature. An additional design 

requirement for joint surface curvature is to balance knee joint 

laxity against knee joint stability. The choice of materials also 

has a major impact on minimizing joint wear. 

WEAR ANALYSIS OF RETRIEVED 

UHMWPE TIBIAL COMPONENTS FROM 

ROTATING PLATFORM TOTAL KNEE 

REPLACEMENTS 

Victor M. Goldberg, M.D; Ryan Garcia, M.D; 

Matthew Kraay, M.D; Clare Rinmac, Ph.D. 



Mobile-bearing total knee replacements (TKRs) were designed 

to increase conformity, decrease contact stresses, and decrease 

polyethylene damage. Our objective was to evaluate the 

performance of retrieved mobile-bearing TKRs with respect 

to wear damage of the polyethylene in a series of components 

obtained at revision surgery. Tibial component polyethylene 

superior and inferior surface damage and radiographic radiolucency 

analysis was conducted on 40 retrieved mobile-bearing 

TKRs. Higher levels of superior articulating surface damage 

were found to be associated with higher levels of inferior surface 

damage in this retrieval study. Greater levels of damage 

were present on both surfaces in components with greater 

radiographic radiolucency scores and mechanically loose component. 

The mobile bearing TKR remains vulnerable to polyethylene 

wear damage at the superior surface and introduced 

an independent inferior surface also vulnerable to wear damage. 

MOBILE BEARINGS: 

ARE THEY WORTH IT? 

Peter Bonutti, MD 


Mobile Bearing is a technology which adds additional cost 

to Knee Arthroplasty. Are there added clinical benefits to justify 

this cost? Numerous factors have been suggested to add 

clinical value in MB TKA. However, a critical review of clinical 

data may not support this. Alleged clinical benefits for MB 

TKA include: 1) “The only knee that bends and rotates” - 

False. 2) Improved function - Not accurate. 3) Improved ROM 

- False. 4) Improved long term survivorship - unproven. 5) 

Reduced polyethylene wear - not proven in in vivo studies. 

6) Improved patellofemoral tracking - inaccurate. 7) “Surgical 

forgiveness” - actually more challenging. In addition, MB TKA 

may have additional complications not found in fixed bearings 

such as bearing subluxations, dislocations, and insert fractures. 

Two recent clinical studies, Ball et al (2006) and Delport et 

al (2006), have suggested possible functional benefit in 

flexion and stair climbing, but these may be design or 

technique specific. 

MB TKA theoretical advantages possibly may be design or 

technique specific, but the majority of clinical literature does 

not prove benefit associated with MB TKA and there is published 

technical complexity and risk. Based on current review 

MB TKA is not worth the additional cost. 

HIGH FLEXION, ROTATING PLATFORM 

TOTAL KNEE ARTHROPLASTY: 

SCIENTIFIC BASIS AND CLINICAL 

EXPERIENCE 

Richard “Dickey” Jones, M.D. 

U.T. Shoutwestern Medical Center. 

Dallas, Texas, (USA) 

High flexion in TKA is any flexion beyond 125°. High flexion 

lifestyle activities such as kneeling or praying are done with 

internal rotation, external rotation, and in neutral. Therefore, 

maximum flexion TKA requires a rotating platform. Superior 

range of motion and fluoroscopic kinematics of femoral rollback 

have been shown with the Sigma RP posterior stabilized 

knee. This knee was modified to produce the Sigma RP-F, 

a maximum flexion knee, by adding a third contact area at 

the post-cam mechanism to significantly increase bearing 

conformity and decrease poly stresses in the range of 125- 

155. Clinical experience is reported with statistically significant 

increase in postoperative range of motion in patients with the 

Sigma RP-F. Patient selection criteria for the Sigma RP-F 

include patients with high flexion lifestyle, younger, more active 

patients demanding a better ROM, and those patients 

with less than 100° preoperative ROM. This knee system 

shows significant promise in providing maximum flexion and 

system longevity is expected.



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15.30 - 16.15 h 


Complicaciones / Complications 

Moderador: Carlos Resines 

EVALUATION OF THE PAINFUL 

TOTAL KNEE 

Thomas S. Thornhill M.D. 

John B. and Buckminster Brown 

Professor of Orthopedic Surgery, Harvard Medical School 

Orthopaedist-in-Chief Brigham and Women’s Hospital 

Boston, Massachusetts (USA) 

1) DIAGNOSTIC TESTS FOR THE EVALUATION OF THE 

PAINFUL TKR 

-history/ physical exam 

-plain radiographs 

-scintigraphy 

technetium/gallium/indium 

-aspiration with synovial fluid analysis 

-arthrography 

-sinograms 

-selective local anesthetic injections 

-articular 

-periarticular 

-phentolamine injection 

-sympathetic block 

-pain unit consultation 

2) CAUSES OF A PAINFUL TKR 

A. Intra-Articular Problems 

- loose bodies 

- overhanging component 

- patellar clunk 

- recurrent hemarthrosis 

- gout/CPPD/RA 

- persistent synovitis 

B. Periarticular Problems 

- pes anserine bursitis 

- patellar tendinitis 

- stress fracture 

- heterotopic ossification 

C. Malalignment 

- MCL strain in valgus knee 

- tibial overload in varus knee 

- rotational impingement 

- patellar subluxation 

D. Instability 

- flexion 

- PCL sag 

- anterior knee pain 

- increased poly wear 

- “start up pain” 

- medial/lateral 

- global 

E. Systemic Problems 

- ipsilateral hip 

- vascular claudication 

F. Neurologic Complications 

- peroneal entrapment 

- reflex sympathetic dystrophy 

- L3/4 HNP 

- neurogenic claudication (spinal stenosis) 

G. Patellar Problems 

- avascular necrosis 

- stress fracture 

- subluxation 

- impingement 

- patellar clunk 

H. Stiff Knee 

- limited pre-op motion 

- tight PCL 

- residual flexion contracture 

- aggressive fibrous tissue response 

I. Patient Issues 

- unrealistic expectations 

- limited pre-operative changes 

- depression 

- family dynamics



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TREATMENT OF STIFFNESS AFTER 


José Romero, MD 

Endoclinic Zurich, Center for Arthroplasty and Joint Surgery, 

Klinik Hirslanden (Switzerland) 

Total knee arthroplasty is a most effective treatment for advanced 

degenerative joint disease of the knee. Although 

satisfactory results can bee expected in most of the patients, 

occasionally the outcome may be compromised by poor 

range of motion after uneventful surgery and postoperative 

course. Stiffness of the knee is a frustrating complication for 

both, the patient and the surgeon. A variety of activities of 

daily living and the overall quality of life is compromised by 

limited flexion and incomplete extension. Stiffness may or 

may not be accompanied by pain at rest, but the attempt to 

forcefully increase the arc of motion is usually very painful. 

Ambulating with a knee that does not fully extend increases 

the muscular work of walking, particularly in the quadriceps 

and decreases endurance. Walking on a level surface is 

possible if the knee flexes only 45° to 55° during swing phase. 

Ascending or descending stairs requires about 85° of flexion. 

Rising from a chair is facilitated if the foot can be brought 

under the seat; this requires at least 95° of flexion. The patient’s 

demands after total knee arthroplasty have increased 

over the last years since most of them enjoy bicycling, mountain 

hiking, skiing and participate in other sports activities 

which require flexion well beyond 90°. Cultural and religious 

habits such as prayer and squatting for eating or hygiene 

require high flexion angles from 125° to 135°. Therefore, the 

definition for stiffness is not absolute and depends on the 

patients demand. In practice, a patient who flexes less than 

100° or lacks more than 10° for full extension considers his 

surgery usually as a failure. If attempts of non-operative management, 

extensive physiotherapy, and perhaps under 

certain conditions manipulation under anesthesia have failed, 

and the knee remains with poor range of motion, surgery 

may be the only option. However, before any operative treatment 

is considered it is mandatory to evaluate the underlying 

condition of the limited arc of motion. 

EVALUATION OF THE STIFF KNEE AFTER TOTAL KNEE 

ARTHROPLASTY 

Mechanical factors such as asymmetric flexion gap as a consequence 

of femoral component malrotation, flexion-extension 

gap mismatch, joint line elevation, femoral component oversizing, 

patellofemoral over-replacement, anterior tibial slope, 

inadequate clearance between the posterior condyles of the 

femoral component and the posterior femoral cortex as a 

consequence of unremoved oseophytes or inadequate posterior 

capping may be responsible for limited motion. Com- 

ponent revision may be very successful if a mechanical 

problem is identified. Since stiffness regardless of the mechanical 

problem is usually painful, adequate pain management 

after revision surgery is crucial for successful outcome. 

Patients hesitate to exercise after revision for stiffness since 

they try to stay away from previous pain patterns. However, 

postoperative flexion-extension exercises are mandatory to 

maintain the range of motion that was achieved intraoperatively. 

Scar formation will lead to a diminution of flexion anyhow, 

but the goal is to loose as few as possible postoperatively. 

A stiff knee without identifiable reason is still a diagnostic 

and therapeutic challenge. Patient factors of biologic origin 

may play a significant role. Knees with severe limitations of 

flexion before primary total knee arthroplasty tend to get 

more flexion postoperatively, but never to the degree of those 

who do not have marked preoperative limitation. A patient 

who starts with 70° to 75° of flexion may end up only at 90° 

of flexion and be satisfied with it. In contrast, patients who 

have 130° of motion preoperatively may feel their knee to 

be stiff with 120° of flexion after primary total knee arthroplasty. 

Multiple studies have documented that preoperative flexion 

is the most important variable in determining the patient’s 

postoperative flexion. A tight posterior cruciate ligament can 

cause limitation of flexion. A knee with a fixed angular contracture 

>15° to 20°, the posterior cruciate ligament often is 

part of the deformity and should be released and be substituted 

for. Obesity per se, as measured by the body mass index, 

is essentially unrelated to range of motion after surgery, particularly 

in patients with truncal obesity but thin legs. However, 

patients with moderate truncal obesity but with heavy legs 

tend to have difficulty regaining flexion after surgery. 

Furthermore, and somewhat more disturbing, there is a subset 

of patients who have high degrees of flexion before total 

knee arthroplasty who never achieve that degree of flexion 

postoperatively. Such a knee shows prolonged swelling and 

develops periarticular fibrosis. The end stage of the disease 

is called arthrofibrosis where the suprapatellar pouch is 

almost obliterated after scar tissue formation between the 

quadriceps and the distal femur, and the medial and lateral 

gutters are scared down. Elasticity of the extensor mechanism 

is markedly reduced which prevents excursion of the quadriceps 

and limits motion. Arthrofibrosis results in serious 

functional impairment, pain, and patient dissatisfaction. 

Biological factors such as autoimmunologic reactions, genetic 

predisposition, reflex sympathetic dystrophy, complex regional 

pain syndrome, metal-related allergy, and low-grade infection 

have been discussed. Connective tissue proliferation with 

deposition of disordered matrix proteins and increased expression 

of type IV collagen in the subsynovial tissue as well 

as around capillary walls are the histopathologic features of 

arthrofibrosis. Further classification of the underlying condition 

which has led to arthofibrosis is not possible. 

Infection is known to induce massive connective tissue proliferation 

and has to be ruled out by aspiration and tissue



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culture in a inflammatory stage. If no germ can be identified 

by aspiration only the clinical course together with the analysis 

of WBC and C-reactive protein may help differentiate between 

infection and aseptic arthrofibrosis. However, a low grade 

infection (if this condition exists) may mimic arthrofibrosis. 

Complex regional pain syndrome (CRPS) is a description 

created by the IASP (International Association for the Study 

of Pain) for an inflammatory disease after surgery or trauma 

which summarizes the terms algodystrophy, reflex sympathetic 

dystrophy, M. Sudeck, causalgia and others. CRPS I is associated 

with nerve damage during surgery, and CRPS II is 

not. Ethiopathology is not well understood, but in both cases 

the sympathetic (autonomous) sensory and motor nerve 

system is disturbed. The symptoms of acute arthrofibrosis 

as a consequence of CRPS consist of pain at rest, which can 

range between moderate and severe, hyperalgia, dysaesthesia 

and skin temperature dysregulation. The skin of the index 

knee can be colder (in 20% of the cases) or warmer (in 80% 

of the cases) than the contralateral knee. Skin color turns 

into red because of increased vascularisation, or it can be 

pale and cyanotic if skin vascularisation is decreased. Hyperhydrosis 

may predominate (50% of the cases) over hypohydrosis 

(20% of the cases). 

TREATMENT OF ARTHROFIBROSIS OF BIOLOGIC 

ORIGIN IN THE ACUTE STAGE 

Any surgical intervention is obsolete during acute stage of 

arthrofibrosis. Diminution of inflammatory clinical signs are 

the goal of initial conservative treatment. Mild physiotherapy 

to maintain mobility but without forcing the knee into a painful 

arc of motion is mandatory. The author has made good experiences 

with alternative treatments such as Osteopathic 

treatment or acupuncture which focus on the autonomic nerve 

system. An invasive approach to block the autonomic 

nerve system consist of lumbar sympathetic blocks. Blockage 

of the sympathetic nerves can also be performed with spinal, 

epidural, or peripheral nerve block, but relief of pain after a 

lumbar sympathetic block will most clearly delineate the 

cause of pain as sympathetically mediated. Most fibers 

headed for the lower extremity pass through the second and 

third lumbar ganglia, so that a sympathetic block with 10-15 

ml epivacain 1% or bupivacain 0.5% placed at this level provides 

almost complete sympathetic denervation of the afferent 

nerve fibers of type C to the lower extremity. Clinical effectiveness 

is only achieved after several injections at an interval 

of a few days. If the patient is unwilling to be treated by 

multiple injections, blockage of the sympathetic system can 

also be achieved by continuous administration of Ropivacain 

0.2-0.3% 6-12 ml per hour with Clonidin 3um per ml and/or 

fentanyl 2ug per ml through a lumbar catheter. With the advent 

of special lumbar catheters a long term treatment of 2- 

3 weeks is possible. Additional oral pain medication with 

non-steroidal anti-inflammatory drugs, paracetamol and 

opioides are always indicated. 

Manipulation under anesthesia (MUA) in an acute stage is 

a controversial procedure, which can accentuate inflammation. 

In the absence of inflammatory signs, examination under 

anesthesia for painful reduced motion in the early postoperative 

phase may help to differentiate between decrease 

flexion as a consequence of mechanical block or pan-induced 

decreased flexion. Examination under anesthesia may be 

followed immediately by true MUA if the knee feels “soft” and 

flexion increases applying gentle force. 

TREATMENT OF ARTHROFIBROSIS OF BIOLOGIC 

ORIGIN IN THE CHRONIC STAGE 

During the inflammatory stage any aggressive procedure is 

counter-productive as it will induce inflammation. This is true 

for closed and open manipulation. Closed manipulation under 

anesthesia can be effective but only if the inflammatory level 

is low. Patients with posterior stabilized knees respond better 

to closed manipulation. Knees with posterior cruciate sparing 

prosthesis have usually a short and tight PCL which can not 

be stretched during manipulation without harming the polyethylen. 

In addition the distal femur may be in risk of fracture 

in such cases. Patients with long lasting stiffness, at least 8 

weeks after primary total knee replacement, arthrotomy is 

the treatment of choice. A technetium bone scan helps making 

the decision whether the arthrofibrosis is still an acute 

stage or whether surgery is safe in a stage where inflammation 

processes have markedly decrease or have completely disappeared. 

At arthrotomy, a complete synovectomy is performed, 

starting with the obliterated suprapatellar pouch where 

the quadriceps tendon is scared down to the femur. The 

quadriceps is liberated, the medial and lateral gutters are 

reconstructed, and a lateral release is performed to increase 

patellar mobility. If the knee can not be exposed properly it 

is safer to performe an osteotomy of the tibial tubercle. This 

prevents avulsion of the patellar tendon which is a catastrophy 

with poor result. It is mandatory to resect the PCL and to 

remove the polyethylen insert for better debridement of the 

posterior aspect of the knee. Usually the posterior capsule 

stays tight enough to resist subluxation without the need to 

revise to a posterior stabilized knee. Trial inserts should be 

available for stability judgment at the end of surgery. It is 

preferable to increase intrinsic stability of the knee with an 

anteroposterior lipped insert if the system allows it (Fig. 1). 

A poor result will be achieved with synovectomy and isolated 

polyethylene insert exchange if a mechanical problem such 

as component malposition or oversizing is the source of 

limited motion. If there is any doubt at trial reduction that stability 

will seriously be compromised, revision to a higher constrained 

knee such as CCK might be considered (Fig 2). In 

selected cases the collateral ligaments need to be scarified 

and revision will only be successful with rotating hinge total 

knee in order to establish femortibial stability. Therefore, 

good preoperative judgment of postoperative stability patterns 

is needed in order to plan for panning the appropriate implant. 

Pain management as mentioned above is essential after surgigal 

intervention, but also after MUA. The goal is to achieve 

at least 90° of flexion. In general, if the patient starts with far 

less flexion than 90° and he achieves an arc of motion that 

goes somewhat beyond 90° of flexion, sometimes even to 

100 or 110°, he usually is satisfied and the intervention was



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Fig 1. Extensive scar tissue has been removed from the hole knee 

including in the posterior aspect where the posterior cruciate ligament 

is resected. The polyethylene insert has been exchanged into a anteroposterior 

lipped insert to prevent posterior subluxation after reduction. 

Fig 2. Revision into a higher constrained CCK-type of implant is necessary 

if stability at trial reduction is compromised. An osteotomy of the tibial 

tuberosity long enough for secure fixation has been performed to gain 

access into a severely stiff knee. The patella baja has been corrected 

by cranialisation of the tibial tuberosity. Fixation is secured by a onethird-tubular 

plate and bicortical screws. This allows aggressive rehabilitation 

to maintain as much of the knee flexion that has been achieved 

intraoperatively. 

relative successful. Sometimes gained arc of motion gradually 

reduces if pain remains or increases over time. Long lasting 

pain medication may be needed and antidepressive medication 

may support the mental state of such difficult patients. 

BIBLIOGRAPHY 

- Haidukewych GJ, Jacofsky DJ, Pagnano MW, Trousdale 

RT. Functional results after revision of well-fixed components 

for stiffness after primary total kneearthroplasty J Arthroplasty 

2005; 20(2): 133-138. 

- Laskin RS, Beksac B. Stiffnesss after total knee arthroplasty. 

J Arthroplasty 2004; 19(4, Suppl 1): 41-46 

- Malony WJ. The stiff total knee arthroplasty. J Arthroplasty 

2002; 17(4, Suppl 1): 71-73 

- Ries MD, Badalamente M. Arthrofibrosis after total knee 

arthrolasty. Clin. Orthop. 2000; 380: 177-183 

- Romero J, Borgeat A, Cartier P. Patella baja. Arthroskopie 

1999; 12: 237-245 

DIAGNOSIS AND MANAGEMENT 

OF MID- FLEXION INSTABILITY 

FOLLOWING TKR 

David Dalury 

John Hopkins Hospital, 

Baltimore (USA)



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16.30 - 18.30 h 


Rodilla de revisión / Revision knee 

Moderador: Richard “Dickey” Jones 

HOW TO DECREASE WEAR IN TKR 

David Dalury 

John Hopkins Hospital 

Baltimore (USA) 

Polyethylene wear is an inevitable aspect of TKR. Early TKR 

designs had little osteolysis and wear. Mid 1980s designs 

which introduced modularity had higher rates of wear. Newer 

designs addressed shortcomings such as poorer locking 

mechanisms, flat on flat designs and improved polyethylene. 

The most intriguing “newer” design is the rotating platform. 

Rotating platforms decrease wear by increasing contact area 

and decreasing contact stresses. 

Wear in TKR can be decreased by appropriate surgical 

technique, implant design and patient selection. This paper 

will discuss these topics in detail.



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THE EXTENSOR MECHANISM IN 

REVISION TKA 

Jan Victor 

Assebroek Brugge (Belgium)



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CONSTRAINT IN REVISION TOTAL 

KNEE ARTHROPLASTY 

Keith R. Berend, MD 

Joint Implant Surgeons, Inc., The Ohio State University, 

Mount Carmel Health System 

New Albany, Ohio (USA) 

The goals of total knee arthroplasty (TKA) are to relieve pain, 

restore function, and provide the patient with a stable joint. 

In regard to types of implants, the workhorses are posterior 

cruciate retaining (CR), posterior stabilized (PS), and posterior 

stabilized constrained (PSC) designs. However, there is a 

continuum of constraint now available that ranges from cruciate 

retaining to a CR lipped device, to an anterior stabilized 

(AS) device, to a posterior stabilized device, to a PS “plus” 

that fits with a PS femoral component but provides a small 

degree of varus-valgus constraint, to a PSC or constrained 

condylar type of device, to a rotating hinge. 

As the degree of deformity, bone loss, contracture, ligamentous 

instability and osteopenia increases, so does the demand 

for prosthetic constraint. 1-3 When compromise is minimal 

and the posterior cruciate ligament (PCL) is intact and without 

deformity, a cruciate retaining device is appropriate. 3,4 For 

moderate compromise with deficiency or compromise of the 

PCL, an anterior stabilized or posterior stabilized device is 

warranted. In severe cases, with attenuation or absence of 

either of the collateral ligaments, a constrained condylar device, 

with options of stems, wedges and augments, is advisable. 

In salvage situations, when both collaterals are compromised, 

a rotating hinge should be utilized. 

Prerequisites for use of a posterior cruciate retaining device 

in revision TKA are an intact PCL, balanced medial and lateral 

collateral ligaments, and equal flexion and extension gaps. 

Possible scenarios include a polyethylene liner exchange as 

part of an incision and debridement for early infection or hematoma, 

a polyethylene liner exchange as part of a procedure 

to resurface, realign or revise the patella in a knee, and 

the revision of a failed unicompartmental knee arthroplasty. 

With a CR lipped bearing, a slight posterior lip is incorporated 

into the sagittal profile of the component to provide a small 

amount of extra stability in the articulation. It is important for 

the surgeon to be aware of the design features of the implant 

system he or she is using. For example, in a system where 

the CR bearing has 3 degrees of posterior slope and the CR 

lipped bearing has no slope, the thickness of a CR lipped 

bearing posteriorly is approximately 2 mm greater than the 

standard CR bearing. A CR lipped bearing would be indicated 

in a revision for instability where the flexion gap is just slightly 

looser than the extension gap and the PCL is intact. This 

might occur at the time of an incision and debridement for 

hematoma or infection, or a patellar revision. In a scenario 

where the patient’s knee is somewhat lax in flexion and stable 

in extension, a CR lipped bearing may help to stabilize both 

the flexion and extension gaps while still allowing the knee 

to obtain full extension, whereas if a CR standard bearing in 

the next thicker size is used to stabilize the flexion gap, a flexion 

contracture may result. 

Anterior stabilized bearings are required infrequently. An 

indication in revision TKA for such a device would be when 

the femoral and tibial components are well fixed, the flexion 

and extension gaps are balanced, but the PCL is deficient, 

and the surgeon does not want to change the well-fixed CR 

femoral component. 

Like the anterior stabilized bearing, the posterior stabilized 

bearing is indicated when the flexion and extension gaps are 

balanced, the medial and lateral collateral ligaments are 

balanced, and the PCL is incompetent. If the tibial component 

is well fixed and aligned, but the femoral component is loose, 

the surgeon can revise to a posterior stabilized component. 

If there is concern about slight asymmetry of the medial and 

lateral collateral ligaments, the surgeon may wish to consider 

using a posterior stabilized plus type of bearing, which will 

fit in the housing of a posterior stabilized femoral component 

and will add just a little more stability while allowing for approximately 

2 degrees of internal and external rotation. 

The posterior stabilized constrained component, which 

provides varus-valgus constraint, is the workhorse for revision 

total knee arthroplasties. It is indicated in cases where a 

complete revision of the femoral and tibial components is 

required and there is attenuation of the medial or lateral 

collateral ligament. A posterior stabilized bearing will not 

provide varus-valgus stability. Specific indications for a PSC 

device are in knees compromised by attenuation of the medial 

collateral ligament secondary to valgus malalignment with 

inability to obtain satisfactory varus/valgus stability in both 

flexion and extension, in knees complicated by an incompetent 

PCL and inability to obtain symmetry in both 

flexion and extension, in knees complicated by varus/valgus 

instability with or without flexion-extension gap symmetry 

and in cases of recurrent dislocation of a PS TKA. 

The rotating hinge is indicated in salvage situations for gross 

instability, where both the medial and lateral collateral ligaments 

are compromised and incompetent. 

The take-home message is that stability is critical. Don’t leave 

the operating room without it. 

SUGGESTED READING 

1. Lombardi AV Jr, Mallory TH, Eberle RW. Constrained 

Knee Arthroplasty. In: W. Norman Scott (editor). The Knee, 

(Vol 2), St. Louis: Mosby-Yearbook, Inc., pp. 1305-1323, 

1994.



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2. Lombardi AV Jr, Mallory TH, Eberle RW. Constrained 

Knee Arthroplasty. In: Kelly G. Vince (editor). Surgery of 

the Knee, (Vol. 2), Baltimore: Williams and Wilkins Medical 

Publishing Co., pp. 1331-1349, 1994. 

3. Lombardi AV Jr, Berend KR. Posterior Cruciate Ligament 

Retaining, Posterior Stabilized, and Varus/Valgus Posterior 

Stabilized Constrained Articulations in Total Knee Arthroplasty. 

In: Terry R. Light (ed). Instructional Course Lectures. 

American Academy of Orthopaedic Surgeons, Rosemont, 

IL. Volume 55, Chapter 44, pages 419-427, 2006. 

4. Lombardi AV Jr, Mallory TH, Fada RA, Hartman JF, Capps 

SG, Kefauver CA, Adams JB. An algorithm for the posterior 

cruciate ligament in total knee arthroplasty. Clin Orthop 

392: 75-87, 2001. 

GRAFTS AND AUGMENTS IN REVISION 

KNEE ARTHROPLASTY 


Northwestern University Feinberg Scool of Medicine 


DEALING WITH SEVERE FEMORAL BONE 

LOSS IN REVISION TOTAL KNEE 

ARTHROPLASTY 

Keith R. Berend, MD, Adolph V. Lombardi, Jr., MD, 

FACS; Joint Implant Surgeons, Inc.; The Ohio State University, 

Mount Carmel Health System, 

New Albany, Ohio, (USA) 

Severe distal femoral bone loss and instability in revision 

total knee arthroplasty (TKA) is a challenging clinical scenario. 

Surgical options include allograft composite reconstruction 

and distal femoral replacement. We reviewed the indications 

and outcomes of 39 OSS (Orthopaedic Salvage System; 

Biomet, Inc.) rotating-hinged distal femoral replacement 

procedures used in 37 patients. Average patient age was 

76 years (SD: 10 years). Indications for hinged prosthetic 

distal femoral replacement included: 11 revision TKA, 13 periprosthetic 

fractures, 11 reimplantations, 2 complex primary 

TKA, 1 distal femoral non-union, 1 acute distal femur fracture. 

Follow-up averaged 45 months. Eight patients died during 

follow-up. There were 5 reoperations: 2 cases of recurrent 

infection following 2-stage treatment; one requiring repeat 

2-stage, and one requiring amputation. One periprosthetic 

fracture occurred. One late hematogenous infection was 

treated with successful irrigation and drainage. One patient 

underwent bearing exchange to treat hyperextension. No 

failures from aseptic loosening were seen. Knee Society 

clinical scores improved from 39 pre-operatively to 87 at 

most recent follow-up. Pain scores improved from 18 preoperatively 

to 43. Distal femoral prosthetic replacement with 

a tumor-type implant in severe cases provides excellent pain 

relief and function with a low rate of reoperation and an 

implant survivorship of 89.8%. 

REFERENCES 

1. Appleton P, Moran M, Houshian S, Robinson CM: Distal 

femoral fractures treated by hinged total knee replacement 

in elderly patients. J Bone Joint Surg 88Br: 1065-1070, 

2006. 

2. Barrack RL, Lyons TR, Ingraham RQ, et al: The use of a 

modular rotating hinge component in salvage revision total 

knee arthroplasty. J Arthroplasty 15(7): 858-866, 2000. 

3. Bezwada HP, Shah AR, Zambito K, et al: Distal femoral 

allograft reconstruction for massive osteolytic bone loss 

in revision total knee arthroplasty. J Arthroplasty 21(2): 

242-248, 2006. 

4. Harrison RJ Jr, Thacker MM, Pitcher JD, et al: Distal femoral 

replacement is useful in complex total knee arthroplasty 

revisions. Clin Orthop 446: 113-120, 2006. 

5. Lombardi AV Jr, Berend KR: The role of constraint in revision 

TKA: Striking the balance. Orthopedics 29(9): 847- 

849, 2006. 

6. Springer BD, Sim FH, Hanssen AD, et al: The modular 

segmental kinematic rotating hinge for nonneoplastic limb 

salvage. Clin Orthop 421: 181-187, 2004. 

7. Utting MR, Newman JH: Customised knee replacements 

as a salvage procedure for failed total knee arthroplasty. 

Knee 11(6): 475-479, 2004. 

TANTALUM AND REVISION TKA 




Managing bone defects is an essential skill for the knee 

reconstruction surgeon in order to re-establish a stable 

foundation on which to place the implant and obtain stable 

long-lasting fixation. Loss of bone frequently occurs simply 

from removing well fixed implants but can also occur from 

a combination of passive effects, such as stress shielding, 

as well as from active wear debris type lytic processes. 

Defect reconstruction can be done in a number of ways, and 

reasonably good literature support can be found for the use 

of each technique.



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Smaller defects are treatable by placement of supplemental 

bone cement, and this can be reinforced with strategically 

placed bone screws. Unfortunately it does nothing to restore 

bone stock. Particulate graft is particularly appropriate for 

smaller or even larger defects. It is readily impacted to fit 

existing defect shapes, requires minimal removal of healthy 

bone and re-vascularizes without losing structural strength. 

But in order to pack the graft these defects must be well 

contained. Lotke has recently shown impressive results in 

expanding this technique to more complex defects by constraining 

large unconstrained defects with mesh and impaction 

grafting the defect with particulate graft. Hopefully these 

techniques will provide some restoration of bone for future 

reconstruction if ever needed. 

Bulk allogeneic bone graft has traditionally been found useful 

in cases of more massive bone loss, particularly in unconstrained 

defects, such as is seen with loss of an entire condyle, 

plateau or even the entire end of the bone. The downside 

of such grafts is that they frequently require removal of some 

native bone to achieve a stable junction and when revascularized 

at long term tend to fail from fatigue stresses. 3,7 

Each technique has advocates and particular settings where 

they are most useful and so the literature does not point to 

any specific technique which would favor one over the other, 

that is, whether you use metal augments or bone graft, and 

there’s a range of options that are available, which are safe, 

and effective provided the reconstruction is done well and 

then protected from excessive stress. 7 Thus, regardless of 

bone defect management technique used, longevity of the 

construct will depend on the restoration of limb alignment, 

ligamentous balance of the knee, and maximizing the intrinsic 

stability of the implant. So in almost all revision situations 

utilization of a stem which protects the reconstruction will be 

an essential part of the operation. 3,4,7 

Clearly the use of smaller augments on the femur and the 

tibia have allowed the reconstructive surgeon to both manage 

defects and fine tune the reconstruction, particularly on the 

femoral side where rotational and joint line positioning may 

be accomplished with these devices. 7 As these augments 

have become routinely available in the revision systems on 

the market, smaller bulk bone grafts have become more 

rarely used 7 and the use of these augments has become an 

increasingly popular choice of the reconstructive surgeon, 

as these modular assembly systems have become more 

readily available. 

However it is rare for the surgeon to make up for greater 

than 1 cm deep defects with such augments. Larger defects, 

have traditionally required bulk grafting when the defect is 

too large for a metal augment. 3,7 

As noted above structural allograft does have some particular 

downsides in addition to the potential for disease transmission. 

7 Particulate graft appears to be more desirable but 

is not amenable to use without extensive re-inforcement in 

the setting where mechanical support is needed. Thus a 

combination of metal augments and bone graft to supplement 

and compliment one another would seem to be desirable. 

This technology has been demonstrated at the hip. 4,6,8 The 

use of trabecular metal along with trabecular metal augments 

to manage local bone defects has dramatically altered the 

way significant defects at the acetabulum are managed. As 

a consequence this technology has been adopted for use at 

the knee where trabecular metal has already been used to 

augment patellar defects. 5 

Trabecular metal is an outstanding material for both bone 

ingrowth and as a scaffolding for new bone formation. The 

trabecular metal is sufficiently porous that it rapidly becomes 

almost completely invaded with bone. 1 In addition, trabecular 

metal allows for an outstanding interface with cement so 

cement can be intimately applied to the trabecular metal with 

development of an outstanding bond. 2 

A system of trabecular metal implants to treat a full range of 

defects at the knee has been developed. These implants 

allow for maximum intra-operative adaptability using modular 

assemblies based on anatomic shapes as opposed to the 

geometric shapes that have been used traditionally. The 

concept is to optimize fixation of the structural augment by 

means of bone ingrowth in areas of host contact, and to 

supplement this region with particular graft. The augment 

thus serves 2 major purposes; structural support for the implant 

and containment of supplemental particulate graft. There are 

a series of metaphyseal augment cones available, as well 

as step cones can make up for larger defects on one side 

and full cones when there is symmetric loss of bone from 

the upper-end of the tibia. The femoral augments are designed 

to fit with standard revision femoral components and will 

supplement distal femoral bone loss, and allow particulate 

grafting about the component and the augment to allow for 

the buildup of a construct of metal and bone. 

The principles here are to use standard augments when 

possible, but when major metaphyseal damage precludes 

stability of this constructthese, these trabecular metal cones 

can be used for initial mechanical support but should also 

allow for biologic ingrowth which can provide long lasting 

mechanical support. In addition, large mechanical void spaces 

can be supplemented with particulate graft. And then finally, 

cement can be used to bond prosthesis to the trabecular 

metal foundation, while stem fixation in intact diaphyseal 

bone can be used to supplement implant stability. 

This method allows for both prosthetic augmentation and 

bone graft support in a complimentary fashion for more severe 

metaphyseal defects. Experience is still early, as these 

augments have only been available for the past two and a 

half years. However the early radiographic and clinical results 

at the hip are promising and it is expected that this technique 

will allow reestablish early weight bearing by strong mechanical 

augmentation support as well as providing for complimentary 

bone stock restitution with use of particulate bone 

graft.



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REFERENCES 

1. Christie MJ. Clinical applications of Trabecular Metal. Am 

J Orthop. 2002 Apr;31(4):219-20. 

2. Cohen R. A porous tantalum trabecular metal: basic science. 

Am J Orthop. 2002 Apr;31(4):216-7. Review. 

3. Dennis DA, Little LR. The structural allograft composite 

in revision total knee arthroplasty. Orthopedics. 2005 

Sep;28(9):1005-7. 

4. Gross AE, Goodman SB. Rebuilding the skeleton: the intraoperative 

use of trabecular metal in revision total hip 

arthroplasty.J Arthroplasty. 2005 Jun;20(4 Suppl 2):91-3 

5. Nelson CL, Lonner JH, Lahiji A, Kim J, Lotke PA. Use of 

a trabecular metal patella for marked patella bone loss 

during revision total knee arthroplasty. J Arthroplasty. 

2003 Oct;18(7 Suppl 1):37-41. 

6. Paprosky WG, O’Rourke M, Sporer SM.The treatment of 

acetabular bone defects with an associated pelvic discontinuity. 

Clin Orthop Relat Res. 2005 Dec;441:216-20. 

7. Rosenberg AG. The use of bone graft for managing bone 

defects in complex total knee arthroplasty. Am J Knee 

Surg. 1997 Winter;10(1):42-8. 

8. Stiehl JB Trabecular metal in hip reconstructive surgery. 

Orthopedics. 2005 Jul;28(7):662-70. 

BONE GROWTH ENHACING FACTORS 

Thomas J. Moore 

Emory University. Scool of Medicine Atlanta, 

Georgia (USA) 

MANAGEMENT OF PERIPROSTHETIC 

FRACTURES IN TOTAL KNEE 

ARTHROPLASTY 

E. Carlos Rodríguez-Merchán, MD, PhD 

Department of Orthopaedics, La Paz University Hospital, 

Madrid, (Spain) 

INTRODUCTION 

When a treatment option is chosen in a peri-prosthetic fracture 

of the knee, consideration must be given to multiple factors 

including: 

- The status of the prosthetic fixation 

- The degree of comminution of the fracture 

- The proximity of the fracture to the prosthetic component 

- The longitudinal alignment of the limb 

- The degree of displacement of the fracture (table 1) 

- The extent of osteoporosis 

Table 1. Classification of periprosthetic supracondylar 

fractures (Rorabeck et al, Instr Course Lect 1998; 

47:449-458) 

Type 1 Undisplaced fracture – Prosthesis stable 

Type 2 Displaced fracture – Prosthesis stable 

Type 3 Displaced or undisplaced fracture – Prosthesis 

loose or failing 

TYPES OF BONE FIXATION 

- Rush rods plus cement 

- Condylar blade-plate 

- Supracondylar locked rod 

- LISS (better, if rapid mobilization is needed 

TREATMENT OF TYPE 3 FRACTURES 

A displaced or undisplaced supracondylar fracture adjacent 

to a loose or failing total knee implant (type 3 fracture) can 

be treated in one of two ways: like a displaced supracondylar 

fracture (type 2 fracture), with revision of the implant at a 

later date, or with revision of the implant as part of the fracture 

stabilization. 

If the surgeon performs a revision, the implant should be 

replaced with a long-stemmed femoral component, a custommade 

component or tumor prosthesis, or an allograft-implant 

composite that also replaces the damaged distal aspect of 

the femur.



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Early intervention and revision of the femoral component to 

one with a canal-filling stem are the best options for treatment 

of most type-III fractures. The exceptional patient who should 

not have early intervention is one who will benefit from 

delayed revision. In this situation, the fracture can be reduced 

and internally fixed so that the patient can walk safely until 

the revision has been performed. 

Meta-analysis of supracondylar fractures occurring 

proximal to sites of TKAs (McLaren et al, Clin Orthop 

Rel Res 1994;302:194-8): 

Satisfactory Outcomes 

Treatment method Total No. Percent 

Close reduction 123 70 57 

Open reduction 63 42 67 

External fixation 6 4 

Intramedullary nailing 6 6 

Revision with long- 25 24 96 

stemmed femoral 

component 

CONCLUSION 

Satisfactory clinical results have been obtained consistently 

with use of a variety of implants and techniques to treat 

periprosthetic femoral fractures proximal to a total implant 

with revision of the component.



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