Fractures of the femoral neck treated with a bipolar endoprosthesis

Seventy-five patients with 77 bipolar hip endoprostheses were reexamined and had roentgenograms taken at an average of 51 months postoperatively. The average age of the patients was 77 years. All prostheses had been inserted due to intracapsular fractures of the femoral neck. Three prostheses had been revised to a total hip arthroplasty at the time of follow-up examination. Radiologically, three cases of protrusion and ten cases with a radiolucent zone greater than 2 mm around the femoral stem were found. Functionally, the result was excellent or good in about 75% of the active ambulators. As acetabular erosion and protrusion appears to have been reduced to some extent, a bipolar hip prosthesis is found to be a good alternative to conventional hemiarthroplasty in elderly patients with a fracture of the femoral neck.