Modified trochanteric flip osteotomy in varus intertrochanteric osteotomy for treatment of Legg-Calvé-Perthes disease

Abstract

Background Legg-Calvé-Perthes disease (LCPD) presents challenges in treatment due to its varied course and unclear etiology. This study aimed to evaluate the efficacy of combining proximal femoral varus osteotomy (PFVO) with a modified trochanteric flip osteotomy to address biomechanical consequences and improve hip abductor muscle strength. Methods We present a modified approach combining PFVO with a trochanteric flip osteotomy. In this technique the greater trochanter in compound with its muscular insertions is separated from the femur and attached distally using a varization blade plate. Eight patients (nine hips) with LCPD were treated using this technique. Clinical examination findings and radiographic evaluations were retrospectively analyzed. The median follow-up was 28 months. Results At the last follow-up, two patients exhibited Trendelenburg gait, but hip abduction was improved in all patients. Radiographically, consolidation at the osteotomy site was observed in all cases, with no delayed union or non-union. The mean CE angle improved by 7.6°, while the mean CCD decreased by 19.5°. The mean MPFA decreased by 17.5° resulting in a mean of 81°. Conclusion Combining PFVO with a modified trochanteric flip osteotomy addresses biomechanical issues associated with PFVO, potentially improving hip containment and abductor muscle strength. This approach may offer advantages over traditional osteotomy techniques in treating LCPD. Despite satisfactory radiological outcomes in most cases, further research is needed to assess long-term effectiveness and address challenges such as femoral head enlargement and persistent gait abnormalities.