UNCEMENTED TOTAL HIP-ARTHROPLASTY IN OSTEONECROSIS - A 2 TO 10-YEAR EVALUATION

All patients undergoing uncemented total hip arthroplasty for end stag e hip disease related to osteonecrosis of the femoral head were assess ed prospectively between November 1983 and October 1992, The results o f clinical evaluation using the Harris Hip score and radiographic asse ssment of fixation were analyzed to identify features of success or fa ilure that may be unique to this population, Four different stem types and 4 different acetabular components were used, Sixty-four patients had 98 hips implanted during the time of the study, The 42 male and 22 female patients averaged 41 years of age (range, 21-69 years), Averag e followup was 87.3 months (7.3 years; range, 31-134 months), The caus e of osteonecrosis was corticosteroids (42 hips), alcohol (27 hips), t rauma (5 hips), and other (24 hips). Three patients (5 hips) have died and 4 patients (6 hips) are lost to followup, At last followup 65 of 87 hips (75%) remained radiographically stable and clinically function al, 18 of 87 (21%) have been revised, and 4 were failing (osteolysis). Of the 22 hips with revision or impending failure, 4 were for technic al reasons on the femoral side and 18 were for acetabular n ear, Patie nt factors such as weight or underlying disease state did not seem to influence the ability to achieve stable fixation or contribute to acce lerated failure. Failures related primarily to problems of first gener ation devices including accelerated wear of acetabular components, tec hnical issues of femoral component placement (undersizing of component s or femoral fracture), and the use of noncircumferentially coated fem oral components. Age may be a factor in early failure, This 10-year ex perience with total hip arthroplasty for the patient with end stage hi p disease due to osteonecrosis suggests that uncemented total hip arth roplasty cast be applied predictably to this younger, potentially more active patient population.