Acetabular Medial Wall Displacement Osteotomy in Total Hip Arthroplasty for Dysplastic Hips

Purpose: This study evaluated the results of acetabular medial wall osteotomy to reconstruct the acetabulum in dysplastic hip during total hip arthroplasty. Materials and Methods: We clinically and radiologically evaluated 30 hips of 30 patients with secondary hip osteoarthritis caused by congenital hip dislocation or acetabular dysplasia who underwent total hip arthroplasty (THA) between March 1999 and October 2002. The average age of subjects was 46.5 years(17 to 73 years), and the mean follow-up period was 5 years(5.3 to 8.7 years). In 26 cases, a cementless hemispherical acetabular cup was inserted in the true acetabulum; in 4 cases a reinforced ring was inserted. Only 2 hips needed structural bone grafting. Results: The average Harris hip score improved from 56.3 points preoperatively to 93.2 points at the last follow up. Radiographic analysis revealed no aseptic loosening or radiolucent line, and showed stable bony fixation at the true acetabulum. The mean thickness of the medial acetabular wall postoperative was 20.5 mm(10 to 36 mm). Bone union of the medial wall was observed at a mean of four months postoperatively. Conclusion: Acetabular medial wall osteotomy can maintain the integrity of the acetabular medial wall while achieving enhanced acetabular coverage and more normal hip biomechanics.