Part I. Amyoplasia: A common, sporadic condition with congenital contractures
Article first published online: 2 JUN 2005
Copyright © 1983 Wiley-Liss, Inc., A Wiley Company
American Journal of Medical Genetics
Volume 15, Issue 4, pages 571–590, August 1983
How to Cite
Hall, J. G., Reed, S. D., Driscoll, E. P. and Opitz, J. M. (1983), Part I. Amyoplasia: A common, sporadic condition with congenital contractures. Am. J. Med. Genet., 15: 571–590. doi: 10.1002/ajmg.1320150407
- Issue published online: 2 JUN 2005
- Article first published online: 2 JUN 2005
- Manuscript Revised: 2 MAR 1983
- Manuscript Received: 8 OCT 1981
A specific congenital contracture (arthrogryposis) syndrome has been recognized in 135 out of 350 patients with various kinds of congenital contractures. This sporadic syndrome, designated amyoplasia is characterized by absence of limb muscles that are replaced by fibrous and fatty tissue. At birth there is characteristic positioning of the limbs with internal rotation at shoulders, extension at elbows, and flexion of the hands at the wrists. Severe equinovarus deformities of the feet are usually present. Contractures at knees and hips occur in a variety of positions. Typically, the face is round with a frontal midline capillary hemangioma and slightly small jaw. Intelligence is normal.
Approximately 63% of our patients had involvement of four limbs (almost always symmetrically), 24% mainly of lower limbs, and 13% mainly upper limbs. Typically, no other malformations are present. However, minor anomalies are seen often, and include hypoplastic digits and hypoplasia of scrotum or labia, the umbilical cord may be wrapped about a limb at birth. In utero fetal activity is decreased and breech delivery is increased in amyoplasia. All cases were sporadic; identical twins are discordantly affected.