Acetabular dysplasia with hip subluxation in Trevor's disease of the hip.

Dysplasia epiphysealis hemimelica (Trevor's disease) is a rare developmental bone disorder characterized by single or multiple epiphyseal intraarticular lesions that are usually unilateral and restricted to one side of the limb. Although the process often is limited to the lower extremity, hip involvement is not common. When it occurs it is more commonly limited to the femoral side. We report a 14-year-old boy with Trevor's disease involving the hip, femoral and acetabular sides, and with progressive dysplasia. We describe a new surgical approach to this rare condition using a two-stage procedure consisting of intraarticular resection of the lesion followed by a modified shelf acetabuloplasty in a second stage to prevent compromise of the proximal femur vasculature, and to allow preservation and improvement of range of motion of the hip. At 36 months followup the patient is pain-free, has full range of motion, improved gait, and no signs of recurrence. Although technically challenging, the two-stage approach to Trevor's disease seems a reasonable and safe method.