UNUSUAL FOCAL DYSKINESIAS - THE EARS, THE SHOULDERS, THE BACK, AND THE ABDOMEN

Fourteen patients with focal or segmental involuntary movements affect ing the ears, back, shoulder girdle, and upper extremity, as well as t he abdomen and pelvic girdle, are presented. The unusual locations and appearance of these dyskinesias distinguishes them from recognized mo vement disorder syndromes. It is argued that the slow, sinuous, and se mirhythmic character of the movements and the variable long-duration b ursts of motor unit activity responsible for them most closely fit int o the spectrum of dystonia. A history of pain in the affected region a nd/or peripheral trauma in some cases also suggests that peripheral fa ctors may play a role in their pathogenesis.