EPIPHYSEAL-METAPHYSEAL ENCHONDROMATOSIS - A NEW CLINICAL ENTITY

We reviewed the cases of eight unrelated children who had an unusual f orm of enchondromatosis characterized by unilateral enchondromas arisi ng within the epiphyseal and metaphyseal regions of the long tubular b ones of the lower extremity. Unlike previously described enchondromas, the lesions developed extensively within the epiphysis before closure of the growth plate and there was direct extension across the epiphys eal growth plate into the metaphysis. The lesions resulted in severe l imb-length discrepancy and angular deformity (which increased in every patient after the time of presentation), asymmetrical premature physe al arrest, and joint incongruity, all of which necessitated numerous o perative procedures. Seven patients had limb-lengthening and one had a Boyd amputation without lengthening. Five patients had a second lengt hening procedure. Twenty-seven osteotomies (range, one to five procedu res per patient) were done; six patients had a repeat osteotomy, Four patients had an epiphyseodesis. We believe that these lesions represen t a previously undescribed clinical entity, which we termed epiphyseal -metaphyseal enchondromatosis.