Arthroplasty in the ankylotic hip.

: A total of 30 cases submitted to arthroplasty for the treatment of ankylotic hip are reported. The clinical results show that movement improved in 63% of the cases, with recovery of normal joint excursion in 37%. Severe limping consequent to hypotrophy of the gluteal musculature persisted in 62% of the cases, requiring the use of two canes in 17% of the patients. There was pain < or = 3 based on the Merle D'Aubigne and Postel evaluation scale in 13% of the patients, while 87% remained totally asymptomatic. Radiographic results were favorable: the incidence of aseptic loosening 86 months after surgery in 25 cemented prostheses was 20% for the acetabulum and 12% for the stem, while the 5 cementless prostheses were stable an average of 27 months after surgery. The incidence of aseptic loosening was greater in patients < or = 45 years of age (30% vs 10%). Early complications included dislocation (6.6%), caused by hypotrophy of the gluteal musculature secondary to the ankylosis. Leg length discrepancy, which was present preoperatively in 10 cases with an interval ranging from -5 to 6 cm (mean 3 cm), was corrected in 6 cases and reduced by half in the remaining 4 patients.