PROPRIOSPINAL MYOCLONUS - EVIDENCE FOR SPINAL PATTERN GENERATORS IN HUMANS

The clinical and electrophysiological characteristics of eight patient s with propriospinal myoclonus are described. Myoclonus developed with in days or weeks of cervical trauma in half the patients. Seven cases had axial flexion jerks, and one axial extension jerks. Myoclonic EMG activity consisted of repetitive bursts with a frequency of 1-7 Hz. Th e jerks in three of the cases were comprised of alternating and rhythm ic bursts of EMG activity in rectus abdominis and the paraspinal muscl es. From these new observations, it is proposed that cervical trauma c an lead to the partial release of a spinal pattern generator. The latt er is capable of recruiting muscles through long propriospinal pathway s into complex rhythmic activity.