Spondylo-megaepiphyseal-metaphyseal dysplasia: a new bone dysplasia resembling cleidocranial dysplasia.

Eight patients are presented who have a generalized bone dysplasia that resembles severe cleidocranial dysplasia but lacks the cranial and clavicular features of that well-defined condition. Vertebral-body ossification is markedly defective, and ossification centers of the tubular bones are grossly enlarged. These patients also differ from those with variant forms of cleidocranial dysplasia described in the literature. It is suggested that they constitute a separate entity sharing some features of cleidocranial dysplasia, and the descriptive term spondylo-megaepiphyseal-metaphyseal dysplasia is offered as a provisional term until it can be more specifically categorized. The condition appears to be transmitted as an autosomal recessive trait.