Abstract
Dysplasia epiphyscalis hemimelica (DEH), also known as Trevor's disease, is a rare developmental disorder affecting the epiphyses; in young children, it usually involves the knee and ankle joints. DEH was first reported by Mouchet and Belot in 1926,1 who named it tarso megalia. In 1950, Trevor2 used the term tarso-epiphyseal aclasis. Fairbank3 in 1956 coined the term dysplasia epiphyseal hemimelica, the term that remains the common usage name for this unusual condition. All had symptoms of pain in the ankle associated with running or long walks. Upon initial examination, all had restriction of dorsi-flexion and plantar flexion of the ankle of 10° or more compared with the contralateral side. Both ankle pain and loss of motion increased with time, correlating with increasing joint incongruity as the lesion grew. At the initial surgery, all children were noted to have "misshapen ankles" (Fig. 1). Surgical excision of the DEH lesion resulted in improved plantar and dorsiflexion in all children at each surgical intervention (Fig. 2) to a normal range of passive motion comparable to the contralateral normal ankle. All children returned to full unrestricted activity after surgery. The 3 boys who required a second procedure to restore joint congruity began experiencing a recurrence of pain and limitation of ankle motion 3-4 years after the initial surgery. Surgical removal of the lesions provided considerable subjective and functional improvement in ankle function. Based on this review of 4 children, early removal of DEH lesions is recommended even though complete extirpation of the lesion is usually impossible without excising a segment of the talus or epiphysis large enough to result in permanent compromise of the ankle joint. The objective of the surgery should be to remove the joint incongruity caused by DEH to facilitate smooth function of the articulation, with the realization that the procedure may have to be repeated once or twice before skeletal maturity, when the continued growth of DEH appears to cease. Although 3 of these cases predated the availability of magnetic resonance imaging, imaging the ankle annually to ascertain the extent of cartilage growth and asymmetry secondary to DEH is recommended, so that the developing incongruity can be surgical corrected before secondary adaptive changes occur in the joint.