title: Propriospinal myoclonus in tetraplegic patients: clinical, electrophysiological and therapeutic aspects.
abstract: Propriospinal myoclonus is a rare and relatively little studied complication of spinal cord injury. We report two patients with an extension-producing myoclonus presenting with tetraplegia caused by cervical trauma. Rhythmic extension jerks of the trunk and lower limbs appeared several weeks after their injury in a context of severe spasticity. The characteristics of these jerks were determined by polymyography of 12 muscles. They lasted between 306 and 1127 ms with a frequency of 0.3 to 0.5 Hz. By comparing latencies their origin was found to be in the lumbar cord from which there was a slow (2 m s-1) upward and downward spread. Oral treatment with baclofen and sodium valproate was partially successful in one patient, but ineffective in the other. Intrathecal 75 or 100 micrograms baclofen produced a striking, complete disappearance of myoclonus prompting the implantation and successful use of a baclofen pump in one patient. These two new cases suggest the existence of a lumbar generator in which myoclonic extension jerks originate, and demonstrate a new therapeutic alternative in intrathecal baclofen for patients resistant to oral medication.
authors.affiliation: Service de Neurologie, Centre Hospitalier de la Côte Basque, Bayonne, France.
authors.forename: N
authors.initials: N
authors.lastname: Fouillet
authors.forename: L
authors.initials: L
authors.lastname: Wiart
authors.forename: P
authors.initials: P
authors.lastname: Arné
authors.forename: P
authors.initials: P
authors.lastname: Alaoui
authors.forename: H
authors.initials: H
authors.lastname: Petit
authors.forename: M
authors.initials: M
authors.lastname: Barat
mesh_terms: D000328:Adult; D001418:Baclofen / Q000008:administration & dosage / Q000627:therapeutic use; D004576:Electromyography; D006801:Humans; D007278:Injections, Spinal; D008297:Male; D009125:Muscle Relaxants, Central / Q000008:administration & dosage / Q000627:therapeutic use; D009207:Myoclonus / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D011782:Quadriplegia / Q000150:complications* / Q000534:rehabilitation
chemical_list: D009125:Muscle Relaxants, Central; D001418:Baclofen