Total hip arthroplasty.

A review of 333 consecutive Charnley total hip arthroplasties four to seven years after operation showed that twenty-eight patients had died, and three deaths were directly related to the surgery. The survivors had an average improvement of 46.6 points in their evaluation scores to a level of 91.3 points. Four deep infections occurred for which removal of the prosthesis was required. Thirteen hips dislocated postoperatively, and five of them required additional surgery. Three were four sciatic-nerve injuries and all but one resolved. Wear of the acetabular component was evident in seventeen hips, measuring two millimeters in six and one millimeter in eleven. With the marking system used, accurate measurement of wear was not possible. Roentgenographic evidence of loosening of the femoral component was found in 24 per cent of the hips, atributable more often to the quality of cement fixation than to the position of the components (varus-valgus). Varus loosening of two millimeters or more was associated with lower evaluation scores.