Carpal tunnel syndrome: a complication of idiopathic torsion dystonia.

Carpal tunnel syndrome (CTS) is usually an idiopathic disorder. Certain occupations that require frequent flexion movements of the hand at the wrist are recognized as precipitating the development of CTS. Dystonia can cause similar excessive movements at the wrists. We report the clinical and electromyographic findings of two patients with idiopathic torsion dystonia (ITD), with frequent flexion postures of the wrists, in both of whom typical CTS developed in the more involved hand. It is concluded that nerve entrapment such as CTS has to be considered a possible complication in patients with ITD and other motor control disorders.