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Background: The Charnley stem provides good outcome for 10 years, but several studies find deteriorating results thereafter. However, study populations, techniques and data analysis vary widely. We have studied 240 Charnley stems in a homogeneous group of patients providing clinical, radiological and survival data after 11-14 years., Hypothesis: The clinical and radiological outcome of the Charnley stem is not as good than previously thought., Patients and Methods: Five surgeons implanted 240 femoral stems in a community hospital in Norway using antibiotic impregnated cement and third generation cementing techniques. The Charnley stems were implanted with a Charnley cup in 120 cases and an uncemented hemispherical cup (Duraloc) in 120 cases. The mean age of the patients was 65.5 years and the mean Body Mass Index (BMI) was 26.8. All patients received low molecular weight heparin and antibiotic prophylaxis. Patients were assessed after 10 years by means of Harris Hip Score (HHS)and radiographic evaluation. Implant survival studies were performed after 11-14 years., Results: One hundred and fifty-eight patients were available for clinical and radiographic evaluation after 10 years. HHS improved from 48.4 (95% CI: 46.6-50,2) preoperatively to 87.9 (95%CI: 86.6-89.3) after 6 months and 87.6 (95% CI: 85.3-89.8) at 10 years. Thirty-one stems had been revised, the reasons for revision were loosening (21), infection (five), instability (four) and late perisprosthetic fracture (one). Forty-one stems had one or more signs of loosening.Stem survival was 83.6% using any revisions as end point, and mean estimated stem survival was 12.7 years (12.2-13.3 years)., Discussion: Other studies report survival at mid-term from 83-96%. Our results are in the low-end. Even though our rate of infection was high (2%), the main cause of the poor results is aseptic loosening. We do not know the reason for this high-rate of loosening. As we believe that our technique is adequate and patient population average, we suspect that this rate of loosening is a characteristic of the implant. Results from this prospective cohort study add to the evidence that the Charnley stem should not be used hip arthroplasty unless patient life expectancy is less than 10 years., (Copyright 2010. Published by Elsevier Masson SAS.)

Background: Even though there are multiple studies documenting the outcome of the Charnley low-friction arthroplasty as well as abundant studies on uncemented arthroplasties, there is a dearth of comparative studies of the uncemented acetabular component and a cemented component. In this study we aimed to document the long-term clinical and radiographic outcome as well as component survival in a randomized controlled trial., Materials and Methods: Two hundred fifteen patients (240 hips) were randomly allocated to receive a cemented Charnley cup or uncemented Duraloc 1200 cup. All patients received cemented Charnley stems and were evaluated clinically and radiographically after 6 months, and 2, 5, and 10 years., Results: Harris Hip Scores improved from 48.3 [95% confidence interval (CI) 45.0-51.6] to 90.2 [95% CI 87.9-92.6] in the Charnley group and from 49.3 [95% CI 86.9-91.3] in the Duraloc group at 6 months. After 10 years, the Charnley group's Harris Hip Score was 89.8 [95% confidence interval (CI) 87.0-92.6], and the Duraloc group's score was 87.3 (95% CI 84.1-90.6). In the radiographic analysis after 10 years, there was no statistical difference in the prevalence of radiographic signs of loosening. Nine cups were revised in the Charnley group, and five cups were removed in the Duraloc group. The difference was not statistically significant. There was no statistical difference between the cups when aseptic loosening was the end-point, nor in survival analyses., Conclusions: There is no statistically significant difference in clinical or radiological outcome between the Charnley cup and the Duraloc after 10 years, and no difference in implant survival after 12-14 years. The uncemented Duraloc cup is as good as the cemented Charnley cup after 10 years.