Simultaneous femoral head reduction osteotomy (FHRO) combined with periacetabular osteotomy (PAO) for the treatment of severe femoral head asphericity in Perthes disease

BACKGROUND: The purpose of this study is to describe the midterm clinical and radiologic outcomes of concurrent femoral head reduction osteotomy (FHRO) and periacetabular osteotomy (PAO) in Legg–Calvé–Perthes disease (LCPD) patients with major aspherical femoral head deformities. METHODS: The study included four Perthes patients in Stage IV of Waldenstrom’s classification with a mean age of 10.5 and severe femoral head asphericity. They were treated with a combination of FHRO + PAO and followed for at least 2 years. An evaluation of the radiological outcome of the surgery was carried out based on the lateral center to edge angle (LCEA), the anterior center to edge angle (ACEA), the Tönnis angle, the head sphericity index, the Stulberg classification, the extrusion index, and Shenton’s line integrity. An evaluation of the clinical outcome was made by evaluating hip range of motion (ROM), Harris hip score (HHS), and Merle d’Aubigne´-Postel score. RESULTS: All radiographic measures improved; three patients were classified as Stulberg class II and one as class III. The LCEA, ACEA, and Tönnis angle improved by 29° (from 3° to 32°), 16° (from 14° to 30°), and − 10° (from 18° to 8°), respectively. The mean femoral head sphericity index and extrusion index improved by 12% (from 83 to 95%) and − 33% (from 40 to 7%). No disruption was observed in the postoperative Shenton’s line. According to HHS, all patients have shown excellent hip function, which improved by 27 points (from 69 to 96). Moreover, the hip ROM was increased from 222° to 267°. The follow-up period did not reveal any serious postoperative complications, such as osteonecrosis or conversion to arthroplasty. CONCLUSIONS: Combined FHRO with PAO may improve the hip joint’s morphology and function in patients with residual femoral head deformity and acetabular dysplasia due to LCPD. Despite being considered a complex and demanding hip surgery, these results suggest a more widespread implication of the salvage procedure.