Dystonia musculorum deformans
a genetic, environmental, or idiopathic disorder, usually beginning in childhood or adolescence, marked by muscular contractions that distort the spine, limbs, hips, and sometimes the cranial-innervated muscles. The abnormal movements are increased by excitement and, at least initially, abolished by sleep. The musculature is hypertonic when in action, hypotonic when at rest. Hereditary forms usually begin with involuntary posturing of the foot or hand (autosomal recessive form ) or of the neck or trunk (autosomal dominant form ); both forms may progress to produce contortions of the entire body.