The Pathophysiology of Focal Hand Dystonia

Narrative Review: Focal hand dystonia is a disabling movement disorder, often task specific, that leads to impaired hand use. In addition to a genetic predisposition, environmental risk factors including repetitive use and musculoskeletal constraints are contributory. Although the underlying cause is unknown, recent studies have identified several key mechanisms that may play a part in its genesis. Failure of inhibition, abnormal sensorimotor integration, and maladaptive plasticity seen to be important. Understanding the underlying physiology may lead to the design of novel therapies. Level of Evidence: 5. I HAND THER. 2009;22:109-14.