The Long Term Outcome of Varus Derotational Osteotomy for Legg-Calvé-Perthes' Disease

Background: Varus derotation osteotomy (VDRO) is one of the most popular surgical treatments for Legg-Calvé-Perthes disease yet its long term results have not been assessed. Our purpose was to determine the long term clinical and radiographic outcomes of these patients.

Methods: Forty patients (43 hips) who had undergone VDRO for LCPD who participated in a long term follow-up study a decade ago were approached for the present study.

All patients were treated in our institution during 1959 to 1983 with proximal VDRO.

The patients were invited to for a medical interview and a physical examination. They were also asked to fill out questionnaires and to provide or undergo a standing anteroposterior (AP) pelvic and a lateral hip radiographs during the visit.

Patients were asked to self-grade their hip pain as none, mild, moderate or severe and to grade their back pain using the Visual Analogue Scale (VAS) between 0-10. Details regarding daily function, physical activity, work status and family history were obtained. All participants completed the Harris Hip Score (HHS) with a maximum score of 100 and the Short Form-36 which is composed of 8 sections and has a maximum score of 100.

The physical examination included an assessment of the hip range of motion, leg length discrepancy and the presence of a Trendelenburg sign.

Radiographic parameters evaluated were the Tonnis grade (with a score between 0-3), head size ratio, and the center-edge (CE) angle.