Three-years comparative outcomes of S-ROM versus Wagner cone prostheses in total hip arthroplasty with subtrochanteric osteotomy for Crowe IV hip dysplasia.

BACKGROUND: Total hip arthroplasty (THA) with subtrochanteric osteotomy is a common approach for managing Crowe IV developmental dysplasia of the hip (DDH). This study compares the efficacy and safety of S-ROM and Wagner cone prostheses in this procedure. METHODS: A retrospective study analyzed 68 patients (75 hips) with Crowe IV DDH who underwent THA with subtrochanteric osteotomy between 2013 and 2021, with a minimum 3-year follow-up. Patients were divided into two groups: 36 patients (38 hips) received S-ROM prostheses, and 32 patients (37 hips) received Wagner cone prostheses. Outcomes including surgical duration, intraoperative blood loss, postoperative complications, Harris Hip Score (HHS), Visual Analog Scale (VAS) scores, osteotomy healing time, and factors associating healing were compared. RESULTS: The Wagner cone group had significantly shorter surgical duration and less intraoperative blood loss compared to the S-ROM group. At 3 years, the S-ROM group showed higher HHS and slightly lower VAS scores. Osteotomy healing rates were comparable, but the S-ROM group had shorter healing times. Complication rates were 10.5% (4/38 hips) for S-ROM and 18.9% (7/37 hips) for Wagner cone. Preoperative HHS was an independent predictor of osteotomy healing (OR: 0.611, 95% CI: 0.448–0.832, P = 0.002). CONCLUSION: The Wagner cone prosthesis reduces surgical duration and blood loss, while the S-ROM prosthesis offers superior functional outcomes and faster osteotomy healing. Both prostheses demonstrate comparable safety and healing rates, making them suitable for Crowe IV DDH.