dystonia musculorum deformans

[mŭs′kyə-lôrəm dē-fôrmənz]
n.
  1. A disease, especially of children, characterized by muscular contractions that produce distortions of the spine and hips with the muscles being spastic when in action and without tension when at rest.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.