Total hip arthroplasty through a direct anterior approach for fused hips.

Introduction: Conversion to total hip arthroplasty (THA) from a fused hip is a challenging procedure because of the technical difficulties involved. Here we report the surgical procedure and the early clinical outcome of conversion THA from a fused hip through a direct anterior approach.

Methods: 9 consecutive THAs following hip fusion were performed in 9 patients. Of these, 6 patients had undergone surgical hip fusion and 3 patients had nonsurgical fusion.

Results: The mean time interval between fusion and THA was 29.7 years. The mean follow-up period was 5.2 years. All THAs were performed using a direct anterior approach on a standard surgical table. The mean operative time was 68.7 minutes. The mean intraoperative blood loss was 377 g. All acetabular components were placed within Lewinnek's safe zone. The mean Japanese Orthopaedic Hip Score significantly improved from 54.0 to 73.2. One early anterior dislocation occurred and was treated conservatively. No revision surgery was required.

Conclusions: The direct anterior approach allows for an accurate and less invasive implantation of the total hip components.