Ten-year follow-up of a proximal circumferential porous-coated femoral prosthesis: radiographic evaluation and stability.

We studied the radiographic findings on 48 hips in 48 patients to determine the stability of a proximal circumferential porous-coated femoral prosthesis in cementless total hip replacement. The patients had coxarthrosis related to acetabular dysplasia. The follow-up interval in the study was 10 to 13 years. In 36 patients, migration of the femoral component was equal to or less than 2 mm. No patient showed progressive migration. Revision surgery was performed in 37 patients because of migration of the acetabular components. Intraoperatively, no femoral components demonstrated visible motion under stress of the implant-bone interface, and none had been revised. During the follow-up period, two patients had mild thigh pain. Two others sustained fracture of the femur 11 years after surgery due to a fall. Pedestal formation was observed in 39 patients and calcar rounding in 21. The mean diameter of the medullary cavity around the distal part of the prosthesis increased from 13.6 to 16.3 mm average. We conclude that the proximal circumferential porous-coated femoral prosthesis is stable for more than ten years after surgery. The risk of subsequent periprosthetic fractures in elderly patients, however, is a matter of concern.

Nonself-centering Bateman bipolar endoprosthesis for nontraumatic osteonecrosis of the femoral head: a 12- to 18-year follow-up study.

We studied the long-term results of bipolar endoprosthetic replacement in 12 patients (12 hips) 12 to 18 years after surgery. These patients had Ficat stage III nontraumatic osteonecrosis of the femoral head. The original Bateman universal proximal femoral endoprosthesis, which did not have a self-centering mechanism, was inserted without cement as a primary surgical intervention. Three patients underwent revision surgery, 3, 17, and 17 years after surgery, respectively. The reasons for revision surgery were migration of the stem in 2 patients and migration of both the stem and the outer cup in 1. In the remaining 9 patients, the total Merle d'Aubigné and Postel score was 16.1 +/-1.3 at the time of follow-up. Radiographs showed migration of the endoprosthesis in 1 of these 9 patients. Thus, 11 of the 12 patients retained the endoprosthesis 12 years or more after implantation. We concluded that the original Bateman endoprosthesis was effective in delaying the need for total hip replacement for more than 10 years in patients with Ficat stage III nontraumatic osteonecrosis of the femoral head.