Dysplasia epiphysealis hemimelica: clinical features and management.

Dysplasia epiphysealis hemimelica is a rare developmental bone dysplasia characterized by an osteocartilaginous tumor arising from an epiphysis. We reviewed the clinical and radiographic findings, including magnetic resonance imaging (MRI), of nine new patients with dysplasia epiphysealis hemimelica. The lower limb was involved in all cases with the ankle (talus) and knee (distal femur) being the most common sites. MRI was helpful in defining the site and extent of the osteocartilaginous mass and provided detailed images of associated joint deformity. Often there was a clear plane of separation between the lesion and the normal epiphysis. All cases were observed initially and showed progressive increase in size of the lesion with skeletal growth. Surgical excision was performed in five cases and proved to be difficult. We recommend excision of symptomatic localized, juxtaarticular lesions but do not recommend excision of articular lesions. Postoperative degenerative joint changes occurred in two patients.