Mechanical loosening after hip replacement. Incidence after 10 years in 125 patients.

From our first 186 Charnley hip replacements 125, retained for more than 10 years, were examined clinically and radiographically. There were radiographic signs of definite or probable loosening of one or both prosthetic components in 29 per cent of the hips. However, there was a poor correlation between the clinical and the radiographic results, as 86 per cent of the hips were free from significant pain. The loosening rate for males under 60 years of age at the time of the operation was four times higher than for females in the same age group. We suggest that this high-risk group should be followed radiographically, so that a revision, if necessary, can be considered while the bone stock is still sufficient.