Bipolar versus total hip arthroplasty for hip osteonecrosis in the same patient.

The authors studied 28 patients with bilateral avascular necrosis of the femoral head who were treated with a cementless bipolar endoprosthesis in one hip and cementless total hip arthroplasty in the other. All the hips selected for bipolar endoprostheses were classified as having avascular necrosis of the femoral head Ficat Stage III, and all the hips selected for total hip arthroplasty were classified as having Ficat Stage IV avascular necrosis. After a midterm followup of an average of 6.4 years (range, 4-12 years), 24 of 28 hips that received bipolar endoprostheses were considered satisfactory, whereas 23 of 28 hips in which an arthroplasty was done were considered satisfactory. After a followup of more than 6 years, the cartilaginous space of the acetabulum could be preserved in 25 hips (89.3%) that received a bipolar endoprosthesis. There were no statistical differences in both groups in terms of clinical result, thigh pain, groin pain, osteolysis, dislocation, and revision rate. Total hip arthroplasty is not the preferred treatment for all patients with hip osteonecrosis. In young patients with Ficat Stage III osteonecrosis with Grade 0 or Grade I cartilage, the use of a cementless bipolar endoprosthesis with a bone ingrowth stem may be considered as an alternative to total hip arthroplasty.