Dystonia is a condition where the muscles in one body part contract or twist in an uncontrollable manner, leading to repetitive contractions and contortions of the affected part, pain and discomfort. Dystonia can affect various body parts including the neck, eyelids, mouth and face, shoulder, arm, leg and foot. The affect body part may twist uncontrollably, become tremulous, cramp or be subject to functional difficulties such as altered speech, dragging of feet, inability to use the affected hand etc.