Bipolar hemiarthroplasty for osteonecrosis of the femoral head. A 7- to 18-year followup.

This study evaluated clinical and radiographic results of bipolar hemiarthroplasties for the treatment of osteonecrosis of the femoral head. Forty-eight hips in 35 patients with a mean age of 37 years who underwent primary bipolar hemiarthroplasties were observed for an average of 11.4 years. Osteonecrosis was associated with corticosteroid use (21 patients), alcohol (six patients), idiopathic (four patients), and other conditions (four patients). The average Harris hip score was 46 before surgery and 86 at the time of the final followup. Twenty (42%) hips were radiographic failures, and 12 (25%) hips were revised. Groin symptoms were present in 20 (42%) hips. Radiographic proximal migration greater than 4 mm and osteoarthritic signs of the acetabulum indicated a high risk of groin symptoms. The results were inferior to those previously reported for total hip arthroplasty. Thus, for the treatment of osteonecrosis of the femoral head in which necrotic lesions are wide, the authors no longer use this system and currently use total hip arthroplasty.