Chorea and ballism.

Chorea and ballism are hyperkinetic movement disorders which can be caused by a variety of conditions including metabolic abnormalities, neurodegenerative and immunologic disorders, as well as structural lesions. In addition, paroxysmal dyskinesias may be associated with chorea. Chorea is increasingly recognized as a symptom of a variety of different conditions. The pathophysiologic mechanisms underlying choreic disorders, however, need further elucidation.