Antley-Bixler Syndrome: A Disorder Characterized by Congenital Synostosis of the Elbow Joint and the Cranial Suture

The Antley-Bixler syndrome is a rare disorder characterized by craniosynostosis, midface hypoplasia, radiohumeral synostosis, joint contractures, arachnodactyly, and femoral bowing and fractures. We report four cases with this disorder, all of which had craniosynostosis, midface hypoplasia with characteristic facial appearance, and contractures of bilateral elbow joints. However, femoral bowing, fractures, and arachnodactyly were not seen in our patients. In addition, proximal phalanges of the thumb and the great toe showed deformity of the delta phalanx in two cases. Characteristic features in these cases were the synostotic deformity of the elbow joint; three had radioulnahumeral synostosis, and one had radioulnar synostosis. Therefore, our cases indicated that various synostotic patterns of the elbow joints may exist in this syndrome. It is reasonable to propose that characteristic craniofacial appearance associated with the synostosis of the elbow joints of various forms should be considered minimal diagnostic criteria of the Antley-Bixler syndrome.