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MIÉRCOLES / WEDNESDAY
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