Alpine and cross-country skiing after total hip replacement: 2 cohorts of 50 patients each, one active, the other inactive in skiing, followed for 5-10 years.

2 groups of 50 patients each, matched for age, weight, height, gender and type of implant, were clinically and radiographically examined after THR. Group A regularly carried out alpine skiing and/or cross-country skiing, while group B did no winter sports. At 5 years, no signs of loosening were found in group A, whereas 5/60 implants in group B had signs of loosening, mostly of the femoral component (p < 0.05). At 10 years, 30 patients remained in group A and 27 in group B. No new cases of loosening were found in group B, but 2/30 cases in group A. There was a higher (p < 0.05) average wear rate in group A (2.1 mm) than in group B (1.5 mm). The wear rate was particularly high (3-4 mm) in physically very active patients in group A with localized osteolysis at the interface. It seems likely that in an even longer follow-up, the number of cases of aseptic loosening would be greater in group A than group B. Our findings, combined with the results of previously-published biomechanical studies, do not provide any evidence that controlled alpine and/ or cross-country skiing has a negative effect on the acetabular or femoral component of hip replacements. The results of the biomechanical studies indicate, however, that it is advantageous to avoid short-radius turns on steep slopes or moguls.