Biomechanical behaviour of a French femoral component with thin cement mantle: The 'French paradox' may not be a paradox after all.

OBJECTIVE: Cement thickness of at least 2 mm is generally associated with more favorable results for the femoral component in cemented hip arthroplasty. However, French-designed stems have shown favorable outcomes even with thin cement mantle. The biomechanical behaviors of a French stem, Charnley-Marcel-Kerboull (CMK) and cement were researched in this study. METHODS: Six polished CMK stems were implanted into a composite femur, and one million times dynamic loading tests were performed. Stem subsidence and the compressive force at the bone-cement interface were measured. Tantalum ball (ball) migration in the cement was analyzed by micro CT. RESULTS: The cement thickness of 95 % of the proximal and middle region was less than 2.5 mm. A small amount of stem subsidence was observed even with collar contact. The greatest compressive force was observed at the proximal medial region and significant positive correlation was observed between stem subsidence and compressive force. 9 of 11 balls in the medial region moved to the horizontal direction more than that of the perpendicular direction. The amount of ball movement distance in the perpendicular direction was 59 to 83% of the stem subsidence, which was thought to be slip in the cement of the stem. No cement defect and no cement breakage were seen. CONCLUSION: Thin cement in CMK stems produced effective hoop stress without excessive stem and cement subsidence. Polished CMK stem may work like force-closed fixation in short-term experiment.Cite this article: Y. Numata, A. Kaneuji, L. Kerboull, E. Takahashi, T. Ichiseki, K. Fukui, J. Tsujioka, N. Kawahara. Biomechanical behaviour of a French femoral component with thin cement mantle: The 'French paradox' may not be a paradox after all. Bone Joint Res 2018;7:485-493. DOI: 10.1302/2046-3758.77.BJR-2017-0288.R2.

Selecting the surgical approach for revision total hip arthroplasty.

Selecting the approach for revision total hip arthroplasty is a crucial step in pre-operative planning. Whether the surgical objectives can be reached via a conventional approach or require a specific approach must be determined. The best approach depends on multiple factors including the reason for revision, patient's characteristics, implants requiring removal, previous approach, soft tissue and bone lesions, and surgeon's level of experience. These factors are discussed herein, as well as the potential and limitations of conventional approaches and the indications for specific approaches.

Comparison of the inter- and intra-observer reproducibility of the Crowe, Hartofilakidis and modified Cochin classification systems for the diagnosis of developmental dysplasia of the hip.

INTRODUCTION: Developmental dysplasia of the hip (DDH) leads to multiple treatment challenges during adulthood. Surgical treatment is mainly based on radiographic evaluation of the anatomical alterations. Several classification systems have been described in the published English scientific literature, but the French Cochin classification has not been used very much. Its primary advantage lies in its ability to intricately describe the DDH alterations with a large number of grades. We hypothesized that the inter- and intra-observer reproducibility of the SOFCOT-modified Cochin classification system was equal to that of the Crowe and Hartofilakidis classifications. MATERIAL AND METHODS: Five French orthopaedic surgeons who were DDH experts classified 94 A/P pelvis radiographs (179 hips) using the Crowe (Cr), Hartofilikadis (Ha) and modified Cochin (Co) systems. This evaluation was repeated a second time one month later. The intra-observer reproducibility was determined with weighted Kappa and concordance coefficients. The inter-observer reproducibility was performed by calculating the multirater Kappa coefficient on each of the two data series. RESULTS: For the intra-observer reliability, the average weighed concordance coefficients (95% CI) were 88.62-94.52 for Cr, 89.43-93.80 for Ha and 92.14-95.71 for Co. The average weighed Kappa coefficients (95% CI) were 0.70-0.85 for Cr, 0.67-0.82 for Ha and 0.75-0.83 for Co. For the inter-observer reliability, the Kappa for each assessment round was 0.57 and 0.48 for Cr, 0.43 and 0.44 for Ha, and 0.43 and 0.37 for Co. DISCUSSION: The intra- and inter-observer reliability for the modified Cochin classification system is the same as the one for the Crowe and Hartofilakidis classifications. The theoretical advantage of this classification system should be confirmed by comparing the findings with intra-operative anatomical observations. LEVEL OF PROOF, TYPE OF STUDY: IV.

Is the so-called 'French paradox' a reality?: long-term survival and migration of the Charnley-Kerboull stem cemented line-to-line.

We have evaluated the in vivo migration patterns of 164 primary consecutive Charnley-Kerboull total hip replacements which were undertaken in 155 patients. The femoral preparation included removal of diaphyseal cancellous bone to obtain primary rotational stability of the stem before line-to-line cementing. We used the Ein Bild Roentgen Analyse femoral component method to assess the subsidence of the femoral component. At a mean of 17.3 years (15.1 to 18.3) 73 patients were still alive and had not been revised, eight had been revised, 66 had died and eight had been lost to follow-up. The mean subsidence of the entire series was 0.63 mm (0.0 to 1.94). When using a 1.5 mm threshold, only four stems were considered to have subsided. Our study showed that, in most cases, a highly polished double-tapered stem cemented line-to-line does not subside at least up to 18 years after implantation.

Impaction grafting in association with the Charnley-Kerboull cemented femoral component: operative technique and two- to 16-year follow-up results.

We describe 129 consecutive revision total hip replacements using a Charnley-Kerboull femoral component of standard length with impaction allografting. The mean follow-up was 8.2 years (2 to 16). Additionally, extramedullary reinforcement was performed using struts of cortical allograft in 49 hips and cerclage wires in 30. There was one intra-operative fracture of the femur but none later. Two femoral components subsided by 5 mm and 8 mm respectively, and were considered to be radiological failures. No further revision of a femoral component was required. The rate of survival of the femoral component at nine years, using radiological failure as the endpoint, was 98%. Our study showed that impaction grafting in association with a Charnley-Kerboull femoral component has a low rate of subsidence. Reconstruction of deficiencies of distal bone with struts of cortical allograft appeared to be an efficient way of preventing postoperative femoral fracture for up to 16 years.

[Early femoral osteolysis following Charnley-Kerboull total hip arthroplasty combining a 22-mm zirconia head on polyethylene]. / Ostéolyse fémorale précoce après arthroplastie totale de hanche Charnley-Kerboull a tête zircone 22 sur polyéthylène.

PURPOSE OF THE STUDY: New bearings have been developed to reduce polyethylene wear. Zirconia ceramic is one proposal with attractive tribologic properties. The purpose of this prospective study was to evaluate the clinical and radiological results at least two years after implantation in a continuous series of total hip arthroplasties combining a zirconia head with polyethylene socket. MATERIAL AND METHODS: The series included 56total hip arthroplasties performed in 51 patients (30 females and 21 males), mean age 52.2 +/- 12 years (25-76 years). Prostheses were implanted for primary degenerative disease (43%) and dysplasia (27%). The femoral component was a stainless steel stem with a Morse cone measuring 11degrees 25' for 27 hips and 5 degrees 40' for 28 hips. A 22-mm stabilized yttrium tetragonal polycrystalline zirconia head (Y-TZP) was used. The transtrochanteric approach was used for all arthroplaties with implantation of a cemented Charnley-Kerboull prosthesis. Clinical outcome was assessed with the Postel-Merle-d'Aubligné (PMA) score. Acetabular cup wear and periprosthetic osteolysis were measured on successive AP x-rays of the pelvis. RESULTS: Mean follow-up was 32 months (24-48). None of the patients were lost to follow-up. Mean function score at last follow-up was 17.8 +/- 0.2 (16-18) versus 12.2 +/- 2.6 preoperatively (Wilcoxon, p < 0.0001). There were no cases of implant migration (femoral or acetabular). An endosteal defect by femoral osteolysis in the calcar femoral was observed in 19 of 55 cases. It appeared early between first and second post-operative year and did not progress later. Its surface remained less than 1 cm2 in all cases. We were unable to identify any factor predictive of these osteolytic lesions. DISCUSSION: The short-term clinical results with this type of arthroplasty was comparable with earlier results described with classical Charnely-Kerboull implants using a metal-polyethylene bearing. The Merkel osteolysis observed in this series occurred early for one-third of the hips with no measurable polyethylene wear. We suggest surgeons should be cautious about using the zirconia head. We are continuing our surveillance of these patients.

Total hip arthroplasty for Crowe type IV developmental hip dysplasia: a long-term follow-up study.

A consecutive series of 118 total hip arthroplasties was performed for Crowe type IV developmental hip dysplasia in 89 patients. The mean age of the patients was 52 years. All procedures were carried out through a transtrochanteric approach by the same surgeon. In all cases, the acetabular component was placed at the level of the true acetabulum. The mean lengthening of the operated limb was 3.8 cm. The average follow-up of the whole series was 12.8 years. At the last follow-up evaluation, 29 patients (35 hips) had died or were lost to follow-up at a mean of 11 years. Sixty patients (83 hips) were still alive at a mean follow-up of 16 years. At the time of last follow-up, the mean Merle d'Aubigné hip score was 17.4 compared with 10.6 preoperatively. The survival rate, with revision for any reason as the endpoint, was 78% at 20-year follow-up.

Total hip arthroplasty for the treatment of ankylosed hips : a five to twenty-one-year follow-up study.

BACKGROUND: The purpose of the present retrospective study was to report the long-term results of total hip arthroplasty following a hip fusion. Special attention was paid to the resulting function of both the involved joint and the neighboring joints, as pain in the lower back or knee was the usual indication for conversion. The factors that were likely to influence the functional outcome were analyzed. METHODS: Forty-five consecutive total hip arthroplasties were performed in forty-five patients from 1969 through 1993. The mean age of the patients at the time of the operation was 55.8 years (range, twenty-eight to eighty years). Ankylosis of the hip had been spontaneous in twenty patients and postoperative in twenty-five patients. The mean duration of the ankylosis had been thirty-six years (range, three to sixty-five years). The mean duration of follow-up was 8.5 years (range, five to twenty-one years). No patient was lost to follow-up. RESULTS: The mean hip score, according to the scale of Merle d'Aubigné, was 16.5 1.5 points at the latest follow-up evaluation. Hip function was considered to be satisfactory for forty-one (91%) of the forty-five patients. The definitive score for walking ability was not achieved by the one-year evaluation; it improved notably for two to three years and then it remained stable. At the time of the latest follow-up, the mean arc of flexion was 88 degrees (range, 30 degrees to 130 degrees ). Forty-three (96%) of the forty-five patients had no pain in the involved joint. The only factor that was predictive of the final functional result with regard to walking ability was the intraoperative status of the gluteal muscles. Most patients had effective pain relief in the neighboring joints. The cumulative survival rate at eight years, with revision as the end point, was 96.7% (95% confidence interval, 90.2% to 100%). CONCLUSIONS: The long-term effectiveness of total hip arthroplasty for the treatment of an ankylosed hip was clearly demonstrated in both the involved and the neighboring joints in the present study. However, the preoperative and intraoperative status of the gluteal muscles should be carefully evaluated when this procedure is being considered, as this was the only factor that was predictive of the final walking ability.

Immunohistological study of entheses in spondyloarthropathies: comparison in rheumatoid arthritis and osteoarthritis.

OBJECTIVE: To determine which inflammatory cell types are present in entheses from patients with spondyloarthropathy (SpA) compared with patients with rheumatoid arthritis (RA) or osteoarthritis (OA). METHODS: Enthesis specimens were obtained during orthopaedic procedures in eight patients with SpA, four with RA, and three with OA. After decalcification, the lymphocyte subsets (CD3, CD4, CD8, CD20) in the bone marrow component of each enthesis were measured by an immunohistochemical technique. RESULTS: Oedema and an inflammatory infiltrate were present in all the SpA specimens, being clearly predominant in the bone marrow component of the entheses. The density of all cell types in the bone marrow was significantly higher in the SpA group than in the two other groups. The cell type CD3+ showed the greatest difference between the SpA and RA groups, being increased fivefold in the SpA group. Within the SpA group, CD3+ cells were considerably more numerous than CD20+ cells-a difference from the RA group-and the predominant T cells were CD8+. CONCLUSION: Persistent oedema with an inflammatory infiltrate composed predominantly of CD8+ cells was noted in the entheses of patients with SpA, being predominant in the bone marrow. These results suggest that CD8+ cells may have a key role in local inflammation in SpAs.

The Kerboull acetabular reinforcement device in major acetabular reconstructions.

Sixty consecutive revision total hip arthroplasties were performed with bulk allograft bone supported by the Kerboull reinforcement acetabular device in 53 patients from 1980 to 1987. The average age of the patients at the time of hip revision was 57.7 years. Acetabular bone loss according to the American Academy of Orthopaedic Surgeons grading system was Type III for 48 hips in 41 patients and Type IV for 12 hips in 12 patients. Three failures, defined as radiologic loosening of the socket, revised or not, were reported in this series at a mean 8-year followup. Eight patients died of unrelated causes at a mean of 5 years. No patient was lost to followup. The mean followup of the series was 10 years +/- 3 years. The mean preoperative Merle d'Aubigné hip functional score was 11.7 +/- 2.4 versus 17.4 +/- 0.6 at the latest followup. Consolidation of the graft was considered completed in all 60 hips and occurred by 12 months. Remodeling of the graft proceeded for 3 to 4 years. The survival rate at 13 years was 92.1% +/- 5% using loosening of the acetabular component as the end point. This study indicated that acetabular allograft reconstructions reinforced by the Kerboull acetabular device were able to provide satisfactory long-term clinical and radiologic results.

[Radiographic assessment of polyethylene wear in machined versus molded polyethylene in total hip prosthesis]. / Pénétration radiographique de la tête dans une cupule prothétique en polyéthylène moulé versus polyéthylène usiné.

PURPOSE OF THE STUDY: Wear of polyethylene acetabular components is an important issue in total hip arthroplasty. This study was designed to evaluate differences in polyethylene wear rates between machined and direct compression molded acetabular cups. METHODS: Two hundred thirty-nine prostheses underwent radiographic evaluation using the technique of Chevrot-Kerboull. One hundred thirty-one were all-polyethylene cups machined from extruded bar stock, and one hundred eight were all-polyethylene cups direct compression molded. Both groups, all operated on in 1988, were similar in the acetabular and femoral components, were all cemented, and the acetabular components were all-polyethylene, non metal backed. The femoral components were all Charnley-Kerboull MK III type. Patient weight, average weight, the post-operative PMA score and the duration of the follow-up were similar for the two groups (mean 7.4 years). RESULTS: Results showed a mean linear wear rate of 0.06 mm per year for compression-molded polyethylene and 0.08 mm per year for machined polyethylene. Results were not significantly different. The number of acetabular radiolucencies in zone I (5.5 versus 5.3 p. 100) and the amount of lysis of the proximal part of the femur did not differ between the two groups. The number of excessive wears did not differ either. DISCUSSION AND CONCLUSION: Although polyethylene wear was lower with compression molded acetabular cups than with ram-extruded acetabular cups, results of this study suggest a non significant difference between the two types of components. A more controlled experiment would have to be performed to attribute a difference between two different types of UHMPE processing.

[Femoral reconstruction with massive allograft implanted in a split femur. Mid-term results of 18 reconstructions]. / Reconstruction fémorale par une allogreffe massive implantée dans un fémur ouvert. Résultats à moyen terme de 18 reconstructions.

PURPOSE OF THE STUDY: Extensive loss of femoral bone subsequent to implant loosening raises an unsolved problem. The purpose of this work was to examine mid-term results of 18 iterative total hip arthroplasties with femoral reconstruction using massive allografts performed between 1986 and 1997. MATERIALS AND METHODS: Using the Vives classification, the femoral bone lesions were grade 3 (n =2) and grade 4 (n =16). The reconstruction was achieved with radiated massive allografts measuring 11 to 35 cm implanted in a split host femur. Charnley-Kerboull implants with a long stem were cemented in the reconstructed femurs. RESULTS: Mean follow-up was 4 years 10 months (range 2 to 9 years). Nine complications in 7 hips were observed: 6 trochanter nonunions, two recurrent prosthesis dislocations and 1 femoral fracture. At last follow-up, the functional result was excellent or very good in 12 hips (Merle d'Aubigné classification). A stable fixation persisted for 15 implants and 3 had loosened. Graft-host femur consolidation was achieved in all cases except 1. There were 3 cases with extensive resorption of the graft including 2 associated with loosening of the femoral component. DISCUSSION: Reconstruction of the femur after extensive bone loss using a massive allograft appears to be a useful method for restoring bone tissue and providing immediate mechanical support for the femur.

Prevention of heterotopic ossification in hip arthroplasty. The influence of the duration of treatment.

A retrospective study has been carried out to assess the effectiveness of indomethacin in preventing heterotopic ossification after total hip arthroplasty, and the effect of using it for different periods of time. One hundred and sixty-eight hips operated on in 1983 were not given indomethacin and acted as a control. One hundred and fifty hips operated on in 1988 were given indomethacin and divided into 3 groups: 42 received indomethacin for 5 days, 49 for 11 days and 59 for 45 days. The results indicate that ossification is significantly reduced in those patients receiving indomethacin for 5 and 11 days, but there was no additional reduction when it was given for 45 days. Treatment should begin on the night of operation and continued for 11 days while the patient remains in hospital.

[Functioning of a bone tissue bank in 1998]. / Fonctionnement d'une banque de tissus osseux en 1998.

Last few years, the french legislation and reglementation concerning donated human tissues, safety precautions, and human tissues' uses have been deeply modified. Therefore, tissue banks' organisation, processing of allograft tissue, and the way surgeons use frozen bone graft have changed. Accordingly, authors describe different obligations these activities implicate and practical consequences for tissue banks and surgeons. First, they recall 94' laws and the doctrinal and ethical principles essential to understand current laws and official standards. Then, they specify sanitary rules all tissue banks have to conform to. They detail the different approaches to recovery, processing, preservation and distribution of transplantable bone tissue and expose modalities of the financing by social organisms. It follows practical consequences in bank functioning: supplying, importation, internal organization. In conclusion, authors synthesize surgeon's responsibilities in that specific activity.

Validation of the Ottawa ankle rules in France: a study in the surgical emergency department of a teaching hospital.

STUDY OBJECTIVE: To validate the Ottawa ankle rules to predict fractures in a French clinical setting when they are used by physicians not involved in their development. METHODS: We used a prospective patient survey by emergency physicians in a surgical emergency department of a university teaching hospital of the Assistance Publique-Hôpitaux de Paris. The study group consisted of 416 consecutive patients aged 18 years and older who presented with acute ankle or midfoot injuries in the surgical ED during a 4-month period. Radiography was performed in each patient after clinical evaluation findings were recorded. RESULTS: Forty-nine ankle and 22 midfoot fractures were diagnosed. The decision rules had a sensitivity of .98, a specificity of .45, and a negative predictive value of .99 in detecting ankle fractures, a sensitivity of 1.0, a specificity of .29, and a negative predictive value of 1.0 in detecting midfoot fractures. The rules failed to predict one avulsion fracture in the ankle group. Application of these rules by emergency physicians would have reduced ankle or midfoot radiography requests by 33%. CONCLUSION: Use of the Ottawa ankle rules by French emergency physicians not involved in the rules' development resulted in 99% sensitivity and had a potential of reducing radiography requests by 33%.

Heterotopic ossification after total hip arthroplasty: risk factors and prevention.

A retrospective review of 168 consecutive total hip arthroplasty procedures done in 1983 at the Cochin Teaching Hospital, Paris, France, was conducted to determine the rate of occurrence of heterotopic paraarticular ossification and to look for risk factors for this complication. None of the patients received preventive therapy for heterotopic ossification. Mean age was 66.2 years. The reason for arthroplasty was hip osteoarthritis in every case. The index operation was the first arthroplasty procedure. Heterotopic ossification was noted in 61.3% of patients and was high-grade in 8.3%. The rate of occurrence of heterotopic ossification was not influenced by age, gender, joint destruction, preoperative osteophytosis, duration of the arthroplasty or the occurrence of complications during or after the arthroplasty. However, severe ossification was more common in men that in women (12.7% men versus 5.7% women had grade III ossification) and in patients operated on by relatively inexperienced surgeons (28/8% grade II and III ossifications, versus 14.7% in patients operated on by experienced surgeons). The rate of occurrence of heterotopic ossification in the patients who had no risk factors (60.9%) was not significantly different from that in the overall study population. These data suggest that preventive strategies targeted to specific patient subgroups would probably be ineffective, and that routine preventive therapy of all total hip arthroplasty patients is warranted.

Implementation of the Ottawa ankle rules in France. A multicenter randomized controlled trial.

OBJECTIVES: To assess the impact of the implementation of the Ottawa ankle rules on radiography requests in French hospitals during a 5-month intervention period and the impact of using posters alone to sustain the effect of the rules during a 5-month postintervention period. DESIGN: Multicenter randomized controlled trial preceded and followed by observational studies of radiological practices. SETTING: The emergency departments of 5 Paris university teaching hospitals of the Assistance Publique-Hôpitaux de Paris. PATIENTS: A total of 2218, 1911, and 851 patients-all aged 18 years and older-who were seen for acute ankle or midfoot injuries in emergency departments during preintervention, intervention, and postintervention periods, respectively. INTERVENTION: Implementation of the Ottawa ankle rules by emergency department physicians in the intervention hospitals (using meetings, posters, pocket cards, and data forms). During the postintervention period, posters alone were used to sustain the intervention effect. MAIN OUTCOME MEASURE: Percentage of patients for whom radiography was requested. RESULTS: During the preintervention period, 98% and 98.5% of patients were referred for radiography in the intervention and control groups, respectively. During the intervention period, the mean proportions of patients referred for radiography by physicians was 78.9% in the intervention group and 99% in the control group (P=.03). Between preintervention and intervention periods, a relative reduction of 22.4% (95% confidence interval [CI], 19.8%-24.9%) in radiography requests was observed in the intervention group, while requests increased by 0.5% (95% CI, 0%-1.4%) in the control group. During the postintervention period, the proportion of radiography requests in the intervention hospitals was lower than the proportion observed in the preintervention period (83.1% vs 98%). CONCLUSIONS: Implementation of the Ottawa ankle rules significantly reduced radiography requests in French hospitals. Using a minimal postintervention implementation strategy, the effect of this intervention decreased but persisted after it was discontinued.

Education for outpatients with rheumatic diseases. Evaluation of short-term and medium-term results.

This prospective study was conducted to evaluate the short- and medium-term impact of the outpatient education sessions that have been available at the Cochin Teaching Hospital since 1992. Each patient was asked to complete a ten-item anonymous questionnaire at the beginning of the education session (evaluation 0), immediately after the session (evaluation 1), after six months (evaluation 2) and after 12 months (evaluation 3). Mean numbers of correct answers per patient were calculated. Eight education sessions were evaluated (osteoarthritis, osteoporosis, rheumatoid arthritis, back pain, conservative treatments, surgical treatments, low-calorie diets and high-calcium diets). One hundred twenty-four patients completed the first two questionnaires, 94 (75.80%) completed the six-month questionnaire and 75 (60.5%) completed the 12-month questionnaire. Mean numbers of correct answers were as follows: 5.7 before the session, 7.3 after the session (p = 0.0001), 7.2 after six months (p = 0.0001), and 7.9 after 12 months (p = 0.0001). These results demonstrate that the education sessions significantly improved patient knowledge in the short and medium term. Their impact on quality of life is being evaluated.

Stabilized resection arthroplasty by an anterior approach in trapeziometacarpal arthritis: results and surgical technique.

Resection arthroplasties were performed through a carpal tunnel incision in 72 hands of 57 patients with trapeziometacarpal joint arthritis and coexistent pathology of the anterior hand or wrist. Sixty-nine hands were followed for an average of 44 (range, 12-74 months). Pain relief was excellent in 60 hands, good in 7, and fair in 2, and thumb motion was satisfactory in 64 hands. Mean strength increase was 30%. Scaphometacarpal space loss was 0.5 mm each year, and residual space averaged 3.1 mm at 60 months. There were two failures. The study corroborated the frequent coexistence of other pathology of the anterior area of the hand and wrist, specifically, carpal tunnel syndrome and flexor carpi radialis tenosynovitis. Furthermore it demonstrated the possibility of an anterior approach to treat these conditions via the same incision. After 5 years, functional results remained good despite progressive collapse of the scaphometacarpal space.

Long-term results of Charnley low friction arthroplasty in patients younger than 40.

We reviewed a consecutive series of 145 total hip arthroplasties that were performed between 1969 and 1983 in 113 patients under 40 years (mean age 33 years). Preoperative diagnosis was secondary osteoarthrosis in 49 hips, rheumatoid arthritis or ankylosing spondylos in 40, avascular osteonecrosis in 38, sequelae of septic arthritis in 6 and others in 12.All operations were performed in a standard operating room. A lateral approach was always used. Cemented implants were Charnley prosthesis (20) before 1973 and Charnley-Kerboull prosthesis (125) from 1973 to 1983.There were 2 delayed unions of the trochanter, 3 deep infections, 1 acute and 2 chronics. Recurrent dislocations due to excessive wear of the acetabular component were observed in 3 hips.At the most recent examination in 1994, 90 hips were reviewed, 48 hips had been lost to follow-up between 6 months and 15 years after surgery, 5 patients (7 hips) had died. The clinical and radiological results of the 137 hips followed up at least 2 years were available for the present study with a median follow-up period of 12 years (range 2 to 24 years). Of these 137 hips, 96 had been followed-up more than 10 years (mean 17 years, range 10 to 24 years).At the latest follow-up, the mean functional score in the d'Aubigné scoring system was 16,5 (range 8 to 18). There were 9 definite and 4 probable loosenings of the socket and 6 definite loosenings of the femoral component (5 subsidences and 1 fracture of the stem). The mean amount of the linear socket wear was 1,62 mm for the 137 hips and 2,22 mm for the 96 hips followed up more than 10 years. Cystic granulomatous lysis was observed in the acetabular area (14 hips), in the calcar (64 hips) and in other zones of the femoral cortex (16 hips). Heterotopic ossification was present in 43 hips.Of the initial 145 hips, 19 had been revised: 3 for septic loosening, 1 for fracture of the stem, 6 for excessive wear of the socket with periacetabular osteolysis and 9 for aseptic loosening (8 acetabular and 1 femoral component). Of these 19 revisions, 11 were performed after 10 years.According to these results the overall probability of retention of the prosthesis was 93,7 at 10 years, 81,5 % at 15 years and 77% at 20 years. When excluding the 3 revisions that were performed for septic loosening, the survival rate was 95,4% at 10 years, 84% at 15 years and 80% at 20 years.These results confirm that the long term reliability of total hip arthroplasty in young patients is less good than in older patients. The main cause of failure was aseptic loosening of the socket which was significantly correlated in this study with an excessive amount of wear. Nevertheless these results performed with a classical friction combination metal on polyethylene are similar or better than other reports with use of new friction combination as alumina-alumina. Further reseach will probably allow us to increase the wear resistance of total hip arthroplasty especially in young patients.Currently, the choices adopted in this series remain a good compromise for us that allow to expect good clinical and radiological results in more than 80% of the cases over 15 years.