ABSTRACT
Dystonia is a syndrome of sustained, repetitive, patterned muscle contractions producing twisting (e.g., torticollis) or squeezing (e.g., blepharospasm) movements or abnormal postures that may be present at rest, with changing posture, or when performing a specific motor activity. Severity and extent of involvement, however, can vary considerably from task-specific contractions of a single limb to continuous and generalized contraction of limb and axial muscles.
