EARLY REVISION AMONG 12,179 HIP PROSTHESES - A COMPARISON OF 10 DIFFERENT BRANDS REPORTED TO THE NORWEGIAN-ARTHROPLASTY-REGISTER, 1987-1993

On the basis of data from the Norwegian Arthroplasty Register during t he period 1987-1993, we have compared times to revision for 10 differe nt cemented total hip prostheses. A total of 11,169 patients, with 12, 179 primary total hip replacements (THRs), performed with high viscosi ty cement for primary arthrosis and followed for a maximum of 6.4 year s, were included in this study. The Kaplan-Meier estimate of the overa ll percentage revised after 5 years was 2.5 (95% Confidence Interval: 2.1-3.0). For the Charnley prosthesis (n 6,694), 2.9% were revised aft er 5 years (95% CI: 2.3-3.4). Using Cox regression to adjust for gende r, age, type of cement and use of systemic antibiotic prophylaxis, the Charnley prosthesis was compared with the 9 other brands. The revisio n rate for the Spectron/ITH combination (Spectron acetabulum, ITH femu r) (n 1,034) was only 0.35 (p 0.04) times that of the Charnley prosthe ses. The Elite/Charnley combination (Elite acetabulum, Charnley femur) (n 507) and the Muller Type prosthesis (n 116) showed poorer results with failure rates 2.3 (p 0.01) and 2.7 times (p 0.04) that of Charnle y, respectively. Although the overall results for cemented THRs in gen eral were good, clinically important differences in revision rates wer e demonstrated among the cemented prosthesis brands. Our findings unde rline the need for careful evaluation of different total hip replaceme nts.