CHARNLEY-KERBOULL TOTAL HIP ARTHROPLASTY IN PATIENTS AGED LESS THAN 50 YEARS: LONG-TERM RESULTS

Abstract

Purpose: The purpose of this retrospective study was to evaluate the clinical and radiological results of Charnley-Keroboull total hip arthroplasty performed in patients aged less than 50 years. We searched for factors which might affect wear and sustained fixation.

Material and methods: Among the 2,804 arthroplasties performed in patients aged less than 50 years between 1975 and 1995, we selected randomly 287 (10% of the annual operations). These prostheses were implanted in 222 patients (144 women and 78 men), mean age 40.1±8 years (15–50). All of the arthroplasties were inserted via a transtrochanteric approach. Charnley-Kerboull implants were cemented in all patients using a metal polyethylene bearing. Functional outcome was assessed with the Postel-Merle-d’Aubigné score. Cup wear was measured with the Chevrot technique. The actuarial method was used to calculate prosthesis survival.

Results: At last follow-up, 155 patients (210 hips) were living and had not had a revision procedure at mean 16.1±4.6 years, 23 patients (25 hips) required revision of the acetabular or femoral element, ten patients (10 hips) had died, and 34 patients (42 hips) were lost to follow-up. The mean preoperative functional score was 9.6±2.5 (9–15) versus 17.2±0.8 (9–18) at last follow-up (Wilcoxon rank test p< 0.001). For the acetabular element, there was certain loosening in 15 hips and possible loosening in 24. For the femoral element, loosening was certain for 12 implants and possible for four. Twentyfive hips required revision, including 17 for aseptic loosening. Mean wear was 0.12±0.21 mm (0–2.23). Among the 287 hips, 196 had wear measured at less than 0.1 mm/yr (mean 0.02 mm/yr). Mean overall implant survival, defining revision as failure, was 85.4±5.0% at twenty years (95%CI 78.4–92.4). Among the factors tested, only abnormally rapid wear (> 0.1 mm/yr) was predictive of failure.

Discussion: The results of this series allow us to conclude that total hip arthroplasty using a Charnley-Kerboull implant remains the best solution for young patients in terms of implant survival.