title: Focal myoclonus and propriospinal propagation.
abstract: OBJECTIVE
  To investigate the relationship between axial segmental myoclonus and propriospinal myoclonus.
  
  
  METHODS
  A patient with a 3-year history of axial jerks evoked by physical effort and unexpected somesthetic and auditory stimulations was investigated. Polygraphy with multiple-channel axial and limb EMG recording was performed with off-line analysis.
  
  
  RESULTS
  Spontaneous, somesthetic and acoustic evoked jerks always began in the left rectus abdominis muscle with a single or repetitive EMG burst that could spread to other rostral and caudal muscles without engagement of cranial nerve innervated muscles, consistent with propriospinal propagation. Spontaneous and evoked jerks could however also appear focally in abdominal muscles and remain localized without any diffusion to other muscle segments.
  
  
  CONCLUSIONS
  Focal axial myoclonus and propriospinal myoclonus may coexist. Conceivably the same spinal generator responsible for a monomeric segmental myoclonus may, under conditions of heightened excitability, cause a multimeric propriospinally propagated muscular activation.
authors.affiliation: Institute of Clinical Neurology, University of Bologna, Via Ugo Foscolo 7, 40123, Bologna, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Vetrugno
authors.forename: F
authors.initials: F
authors.lastname: Provini
authors.forename: G
authors.initials: G
authors.lastname: Plazzi
authors.forename: M L
authors.initials: ML
authors.lastname: Valentino
authors.forename: R
authors.initials: R
authors.lastname: Liguori
authors.forename: E
authors.initials: E
authors.lastname: Lugaresi
authors.forename: P
authors.initials: P
authors.lastname: Montagna
mesh_terms: D000328:Adult; D004576:Electromyography; D006801:Humans; D008297:Male; D009207:Myoclonus / Q000503:physiopathology*; D017286:Polysomnography; D013116:Spinal Cord / Q000503:physiopathology*