Treatment of Steroid-Induced Osteonecrosis of the Distal Femoral Condyle Using Structural Bone Grafting.

Abstract

Steroid-induced osteonecrosis of the distal femoral condyle is an uncommon condition that predominantly affects young patients receiving high-dose corticosteroid therapy. Joint-preserving treatment options for precollapse lesions remain limited, particularly in cases with extensive subchondral involvement. The purpose of this study was to evaluate the clinical and radiological outcomes of structural bone grafting (SBG) using a bicortical iliac bone graft (autograft or allograft) for precollapse osteonecrosis of the distal femoral condyle. This retrospective case series included 11 knees in 8 patients with steroid-induced osteonecrosis of the distal femoral condyle who underwent SBG. All treated knees were classified as Association Research Circulation Osseous stage II. Clinical outcomes were assessed using the Japanese Orthopaedic Association (JOA) knee score, and radiological evaluation focused on graft incorporation and the presence of subchondral collapse or degenerative changes. The mean follow-up duration was 150.5 months (48-288 months). No procedure-related complications were observed. Radiological graft incorporation was confirmed in all treated knees, and no progression to subchondral collapse or degenerative changes was identified during the observation period. The mean JOA knee score improved, and no deterioration was observed; 2 knees showed no change, 3 demonstrated modest improvement, and 6 showed greater improvement (15-40 points). SBG using a bicortical iliac bone graft provided favorable long-term clinical and radiological outcomes in this series of patients with precollapse steroid-induced osteonecrosis of the distal femoral condyle. This technique may be useful for carefully selected patients with early-stage disease and extensive subchondral involvement. Level III, Therapeutic. See Instructions for Authors for a complete description of levels of evidence.