HEREDITARY MULTIPLE EXOSTOSES - ANTHROPOMETRIC, ROENTGENOGRAPHIC, AND CLINICAL ASPECTS

In a retrospective review of thirty-two patients with hereditary multiple exosteses, anthropometric data were plotted and the nature and extent of the associated deformities were noted. Although such patients tend to be short, true dwarfism is rare. Mild skeletal disproportion occurs since limb involvement is greater than spinal involvement. The position and relative frequency of exostoses at the metaphyseal regions of the long bones were documented. In the upper extremity, 60 percent of the patients had moderate to severe involvement of the forearm. The distal end of the ulna always was more seriously affected than the radius. Dislocation of the radial head occurred in 22 percent of the elbows that were assessed. Moderate to severe rotational limitation was found in 33 percent of the forearms. In the lower extremity, coxa valga (25 percent) and occasionally femora vara were seen, but these deformities were rarely of clinical signficance. When genu valgum occurred, the valgus deformity was within the tibia itself. Valgus deviation of 5 degrees or greater (mean deviation, 10 degrees) was found in 33 percent of the tibiae assessed, and 20 percent of the patients required an osteotomy at the proximal end of the tibia to correct the deformity. Obliquity of the distal tibial epiphyseal surface was seen frequently, and 54 percent of the ankles assessed were markedly abnormal. The relative shortness of the fibula in relation to the tibia and the abnormally proximal position of the lateral malleous in relation to the medial malleous were documented. Limb-length discrepancies were common. In 50 percent of the patients, the discrepancy was great enough to warrant operative epiphyseal arrest, although this was done in only 23 percent. Operations were performed frequently, with an average of 2.7 procedures per patient. The procedure involved removal of the exostoses, epiphyseal arrest, excision of the radial head, and corrective osteotomy.