1. Fourteen previously unreported cases of melorheostosis are presented. The disease progressed rapidly in the children and slowly in the adults. Contracture and deformity were the earliest findings in childhood and pain and stiffness in affected joints was the most common complaint in adult life. Soft-tissue contractures and deformities, especially in the hands and feet, were usually found and treated before roentgenograms were made which showed the characteristic hyperostosis.

2. Roentgenograms made in infancy or early childhood usually showed a faint linear hyperostosis which was difficult to diagnose. This rapidly increased in the immature skeleton and more slowly in the adult skeleton, eventually producing the appearance of bone flowing along the cortex.

3. Abnormality of the soft tissues of mesodermal origin, as manifested by contractures, was usually discovered earlier than the underlying hyperostosis, often leading to incorrect diagnoses. They usually caused greater deformity and disability than the disease in bone.

4. The pattern of involvement suggests that this disorder is a congenital abnormality akin to paraxial hemimelia and that it is initiated early in embryonic life prior to the formation of the limb buds.