Saint Vitus' dance

"Saint Vitus' dance" is a kind of chorea, the medical term for a neurological disorder causing involuntary, quick, spasmodic movements of the body's muscles. (Chorea comes from the ancient Greek choreia = dance.) In recent medical practice Saint Vitus' Dance, which affects the feet, hands, and face, has come to be known as Sydenham's chorea. It often afflicts children who have had rheumatic fever or other streptococcal infections.

JH 2014

Portrait of St. Vitus in the Nuremberg Chronicle, 1493. Source: Wikimedia Commons.