Myoclonus of the scapula after acute long thoracic nerve lesion: a case report.

We describe a patient who presented myoclonus in the left scapula 3 months after a traumatic lesion of the left long thoracic nerve. Myoclonic activity was recorded as pseudorhythmic electromyographic bursts repeated at a frequency of 2 to 4 Hz, each lasting between 100 and 200 msec, in the left serratus-dorsalis muscle region, trapezius, and deltoid muscles. A combination of peripheral and central mechanisms may have induced the myoclonus in this case.