IN 1901, Gowers1 described two patients with paroxysmal involuntary movements precipitated by initiation of voluntary movement. Since then, few similar cases have been reported. In 1940, Mount and Reback2 described a family in which several members suffered from episodic choreoathetosis and called the disorder "familial paroxysmal choreoathetosis." Subsequently, the same or similar conditions were described with various other titles such as reflex epilepsy,3 periodic dystonia,4 epilepsie bravais-jacksonienne réflex,5 conditionally responsive extrapyramidal syndrome,6 seizures induced by movement,7 hereditary kinesthetic reflex epilepsy,8 and paroxysmal kinesigenic choreoathetosis.9
These paroxysms are characterized by choreoathetotic and tonic movements. They are precipitated by sudden voluntary movement, begin in childhood, and are occasionally familial. The cause is not known, although one patient had a birth injury10 and another a scar of the cerebral cortex.11 The mechanism of the involuntary movements has not been clarified.
Since the disorder