Clinical and radiographic evaluation of long-stem femoral components following revision total hip arthroplasty.

Abstract

Fifty-four consecutive, long-stem revision hip arthroplasties were performed in 53 patients. In order to evaluate periprosthetic femoral changes, all cases utilizing cement, requiring bone-grafts for prosthetic stability, or with a follow-up period of less than 2 years were omitted. Thus, 32 long-stem revision hip arthroplasties in 32 patients were reviewed. Twenty-three Porous Coated Anatomic (Howmedica, Rutherford, NJ) and nine Bi-Metric (Biomet, Warsaw, IN) stems were implanted, with an average follow-up period of 3.6 years (range, 2-6 years). Prosthetic canal fill averaged 94% proximally and 80% distally. Intraoperative complications included three femoral shaft fractures. Harris hip scores averaged 47.8 points, before surgery and 87.6 points at the final follow-up evaluation, with 81% of patients the pain-free. Only three cases of subsidence and one case of osteolysis were noted. By 1 year, proximal osteopenia (off-load) (P = .005), bony condensation about the porous surface (spot weld) (P = .01), and pedestal formation (P = .004) were observed. The presence of distal cortical hypertrophy, (P = .02) spot weld (P = .001), and pedestal formation (P = .05) correlated significantly with off-load. Pedestal formation and distal cortical hypertrophy were commonly found together (P = .001). Despite significant periprosthetic remodeling, adequate fixation and satisfactory early clinical scores were achieved in this setting. Contrary to similar reviews using extensive bone-grafts, acceptable pain-free clinical results were obtained with these components.