Primary care guide to myoclonus and chorea. Characteristics, causes, and clinical options.

Myoclonus and chorea are hyperkinetic movement disorders that confer a jerky appearance. Myoclonus involves a quick and simple jerk, whereas the jerking in chorea combines with other, slower movements in a continuous, flowing fashion. Both disorders have many different causes, and diagnosis requires knowledge of common clinical characteristics and directed ancillary testing. Symptomatic treatment is available, but reversal of the underlying cause should be considered first if possible. The potential benefits of treatment must be weighed against the risk of drug side effects.