Chorea

Chorea, rarely spelled choreia, is an abnormal involuntary movement disorder marked by quick movements of the hands or feet. It belongs to a group of neurological disorders called dyskinesias. The name comes from the Ancient Greek word choreia, meaning dance, because the movements of the body resemble dancing. When the chorea affects only one side of the body, for example one arm but not the other, it is called hemichorea, a term that is analogous to hemiballismus, the one-sided flinging movement disorder. The word is therefore a description of a kind of movement, grouped by neurologists with the other dyskinesias, which are disorders of involuntary movement; the entry covers the movement disorder itself, including its rare spelling choreia and the one-sided form hemichorea.