Procs III 2011.indb - Journal of Bone & Joint Surgery, British Volume ...

360 HELLENIC ASSOCIATION OF ORTHOPAEDIC SURGERY AND TRAUMATOLOGY
124 FACTORS WITH A FAVOURABLE
IMPACT REGARDING THE SURGICAL
TREATMENT OF LEGG-CALVE PERTHES
DISEASE IN CHILDREN
I. Flieger, N. Pettas, A. Leonidou, N. Liarakos, I.
Platanitis, O. Leonidou
Orthopaedic Department, Childrens Hospital
“Agia Sofia”
The cause of Legg-Calve Perthes disease, 97 years after
its original description remains undefi ned. In the present
study we examined factors, which were correlated
with a favourable or negative impact on the outcome of
surgical treatment.
From a total of 98 children, treated during the period
1994-2006, we studied 20 cases (classifi ed as Catterall
III and IV), treated surgically. The average age was 7.4
years (4-13 years). We studied in comparison the most
common procedures performed: these were the varus
femoral osteotomy (12) and the lateral shelf acetabuloplasty
(7). The subtrochanteric osteotomy yielded superior
radiological results Stuhlberg I-II (I:6, II:6), than the
lateral shelf procedure Stuhlberg II-IV (II:3,III:3,IV:1).
The clinical results were similar between the two groups
according to the Barrett scale, excellent or good.
Regarding the subtrochanteric osteotomy the most
important factor was the precise varisation of the femoral
neck and secondly the timing of surgical treatment
early during the fragmentation stage of the disease,
before the femoral head is signifi cantly distorted. The
most important positive factor regarding the lateral
shelf procedure appears to be the accuracy of the surgical
technique, in order that the graft coverage of the
femoral head is accurately placed on the hip capsule.
Negative factor for the lateral shelf procedure in one
case was early weightbearing, which resulted in collapsing
of the femoral head. It appears that with extensive
necrosis (Caterall IV) the femoral head isn’t biomechanically
enough resistant with this procedure to resist loads
that result from early ambulation.
001 COMPUTER-ASSISTED THREE-
DIMENSIONAL CORRELATION BETWEEN
THE FEMORAL NECK-SHAFT ANGLE
AND THE OPTIMAL ENTRY POINT FOR
ANTEGRADE NAILING
G. Anastopoulos, D. Chissas, J. Dourountakis,
P.G. Ntagiopoulos,G. Stamatopoulos, N.
Zacharakis, A. Asimakopoulos,Th.A. Xenakis
2nd Dpt. of Orthopaedic & Trauma Surgery,
“G. Gennimata” Hospital of Athens, Greece;
Dpt. of Orthopaedic Surgery, University Hospital
of Ioannina, University of Ioannina School of
Medicine, Ioannina, Greece.
Optimal entry point for antegrade femoral intramedullary
nailing (IMN) remains controversial in the current
medical literature. The defi nition of an ideal entry point
for femoral IMN would implicate a tenseless introduction
of the implant into the canal with anatomical alignment
of the bone fragments. This study was undertaken
in order to investigate possible existing relationships
between the true 3D geometric parameters of the femur
and the location of the optimum entry point.
A sample population of 22 cadaveric femurs was used.
Computed-tomography sections every 0.5 mm for the
entire length of femurs were produced. These sections
were subsequently reconstructed to generate solid computer
models of the external anatomy and medullary
canal of each femur. Solid models of all femurs were subjected
to a series of geometrical manipulations and computations
using standard computer-aided-design tools.
In the sagittal plane, the optimum entry point always
lied a few millimeters behind the femoral neck axis
(mean=3.5±1.5 mm). In the coronal plane the optimum
entry point lied at a location dependent on the femoral
neck-shaft angle. Linear regression on the data showed
that the optimal entry point is clearly correlated to the
true 3D femoral neck-shaft angle (R2=0.7310) and the
projected femoral neck-shaft angle (R2=0.6289). Anatomical
parameters of the proximal femur, such as the
varus-valgus angulation, are key factors in the determination
of optimal entry point for nailing.
The clinical relevance of the results is that in varus
hips (neck-shaft angle ≤ 120o) the correct entry point
should be positioned over the trochanter tip and the
use stiff nails is advised. In cases of hips with neck-shaft
angle between 120o and 130o, the optimal entry point
lies just medially to the trochanter tip (at the piriformis
fossa) and the use of stiff implants is safe. In hips with
neck-shaft angle over 130o the anatomical axis of the
canal is medially to the base of the neck, in a “restricted
area”. In these cases the entry point should be located
at the insertion of the piriformis muscle and the application
of more malleable implants that could easily follow
the medullary canal should be considered.
002 FLOW CYTOMETRY LEUKOCYTE
IMMUNOPHENOTYPE INVESTIGATION IN
TOTAL HIP ARTHROPLASTY LOOSENING
M. Ovrenovits, E.E. Pakos, G. Vartholomatos,
G.I. Mitsionis
Haematology Laboratory – Unit of Molecular
Biology, University Hospital of Ioannina;
Department of Orthopaedic Surgery, University
Hospital of Ioannina; University of Ioannina,
School of Medicine, Ioannina, Greece
The aim of the study to analyze the circulating white
blood cells including the intensity expression of surface
receptors and cytoplasmic molecules in patients underwent
total hip replacement, with either aseptic or septic
loosening of hip prostheses in order to identify cell-surface
and cytoplasmic markers that could be indicative
of early loosening. Flow cytometry was performed in
whole peripheral blood samples of 20 patients with
loosening (10 septic and 10 aseptic). Ten healthy individuals
served a control group. The CD62L, CD18,
CD11a, CD11b and CD11c expressions were evaluated.
The mean fl uorescence intensity (MFI) of CD 18
was decreased on all leukocytes subsets compared to
control group. For patients with aseptic loosening we
demonstrated an increase of MFI for CD11b in granulocytes
and for CD11c in monocytes and granulocytes
compared to control group. In patients with septic loosening
an increase of MFI for CD 11c was observed in
monocytes compared to control group. The comparison
between aseptic and septic loosening showed a statistically
signifi cant lower CD18 MFI value in granulocytes
for aseptic loosening. A trend towards lower MFI
values of CD 62L in lymphocytes and granulocytes were
observed in aseptic but not in septic loosening patients
compared to control group. The present study is the fi rst
study in published literature to demonstrate cell surface
and cytoplasmic markers in peripheral blood indicative
of loosening of THAs by means of fl ow cytometry.
003 THE INFLUENCE OF PRP ON TENDON
HEALING. AN EXPERIMENTAL STUDY IN
RABBITS
K. Kazakos, D. Lyras, D. Verettas, A.
Polychronidis, S. Botaitis, G. Agrogiannis
Democritus University of Thrace, Orthopaedic
Clinic
We investigated the effect of Platelet Rich Plasma (PRP)
in tendon healing. The aim was to assess the effect of an
application of PRP on angiogenesis and immunohistochemical
expression of TGF-b1 and IGF-I during tendon
healing.We used a patellar tendon defect model after
resecting its central portion. 48 skeletally mature New
Zealand White rabbits were divided into the respective
group and each group they were randomised into controls
and PRP treated cases. The rabbits were sacrifi ced at
weekly intevals and histological and immunohistological
assessments were performed. The results showed a faster
healing rate, increased vascularity, and higher expression
of the growth factors in the PRP group. We conclude
that the mixture of growth factors present in PRP gel
improved the rate and quality of tendon healing.
004 IS TUMOR RESPONSE TO
PREOPERATIVE CHEMOTHERAPY A SOLE
PROGNOSTIC FACTOR OF SURVIVAL IN
OSTEOSARCOMA PATIENTS?
M. Ioannou, I. Papanastassiou, S. Kottakis, N.
Demertzis
Department of Orthopaedics, METAXA
Anticancer Hospital
In the treatment of osteosarcoma, many reports in the
literature outline that tumor response to chemotherapy
directly correlates with disease-free survival and/or mortality.
The aim of this study is to evaluate if the percentage
of tumor necrosis is a sole prognostic indicator of
overall survival in osteosarcoma patients.
We retrospectively studied 33 osteosarcoma cases
treated in our institution from 1997 to 2006. All
patients were treated preoperatively with HDMTX chemotherapy.The
percent necrosis of the excised specimen
were compared with survival rates of the patients.
Sixteen patients were good responders (Huvos
III,IV- >90% necrosis), 16 patients were poor responders
(Huvos I,II- < 90% necrosis), and one patient died
during preop. chemotherapy.With a mean follow-up of
5,48 years (3-12 years) 22 patients are NOD (not evident
disease), in 8 patient disease progressed, 8 patients died.
Statistical analysis could not establish a signifi cant correlation
between percent necrosis and patient survival.
Outcome of osteosarcoma may be dependent on a
variety of factors s.a. tumor size, location, metastasis,
surgical therapy, pathologic fracture. Tumor necrosis
itself may be dependent on the histological subtype of
the tumor and P-glycoprotein expression. In this series
we could not establish tumor necrosis as a sole prognostic
factor of patient survival.
00 LOW-DENSITY LIPOPROTEIN RECEPTOR-
RELATED PROTEIN 5 (LRP5) GENE
EXPRESSION IN HUMAN OSTEOARTHRITIC
CHONDROCYTES
A. Tsezou, I. Papathanasiou, T. Orfanidou, K.N.
Malizos
University of Thessaly, Medical School,
Laboratory of Cytogenetics and Molecular
Genetics, Larissa, Greece; University of Thessaly,
Medical School, Department of Orthopaedics,
Larissa, Greece; Institute for Biomedical Research
and Technology, Larissa, Greece; University of
Thessaly, Medical School, Department of Biology,
Larissa, Greece
The Wnt/b-catenin signaling pathway participates in
normal adult bone and cartilage biology and seems to be
involved in cartilage degeneration and subsequent OA
progression. The aim of this study was to investigate
the activation of Wnt/b-catenin pathway in osteoarthritis
and the role of LRP5, a coreceptor of Wnt/b-catenin
pathway, in human osteoarhritic chondrocytes.
Human cartilage was obtained from 11 patients with
primary osteoarthritis (OA) undergoing total knee and
hip replacement surgery. Normal cartilage was obtained
from 5 healthy individuals. b-catenin and LRP5 mRNA
and protein levels were investigated using real time
PCR and western blot analysis, respectively. Blocking
LRP5 expression was performed using small interfering
(siRNA) against LRP5 and subsequent MMP-13 mRNA
and protein levels were evaluated by real time RCR and
western blot analysis, respectively.
We confi rmed the activation of Wnt/b-catenin pathway
in osteoarthritis, as we observed signifi cant upregulation of
b-catenin mRNA and protein expression in osteoarthritic
chondrocytes. We also observed that LRP5 mRNA and
protein expression was signifi cantly up-regulated in osteoarthritic
cartilage compared to normal. Also, blocking LRP5
expression using siRNA against LRP5 resulted in a signifi -
cant decrease in MMP-13 mRNA and protein expressions.
Our fi ndings suggest that the upregulation of LRP5
mRNA and protein expression in osteoarthritic chondrocytes
results in an increased activation of Wnt/b-catenin
pathway in osteoarthritis. The observed reduction of MMP-
13 expression after blocking LRP5 expression in osteoarthritic
chondrocytes, suggests the involvement of LRP5 in
the progression and pathogenesis of osteoarthritis.
J BONE JOINT SURG [BR] 2011; 93-B:SUPP III