title: Neurophysiological correlates of sleep leg movements in acute spinal cord injury.
abstract: OBJECTIVE
  The objective of this study was to analyze the periodicity of leg movement activity emerging during sleep in a group of patients with spinal cord injury and to evaluate their pathophysiological features.
  
  
  METHODS
  Twenty patients (16 males, mean age 34.0 years) with traumatic spinal cord lesions were recruited (5 cervical, 15 thoracic; 16 level A and 4 level B at the American Spinal Injury Association impairment scale). Periodicity of sleep leg movements was analyzed; electroencephalographic spectral analysis and heart rate were evaluated for 20s preceding and 30s following the onset of leg movements.
  
  
  RESULTS
  Periodic leg movements during sleep (PLMS) index >5/h was found in only 4 patients and only 2 of these had PLMS index >15/h. Eleven patients (group I) did not show any increase in heart rate related to the occurrence of leg movements while the remaining 9 did (group II). Two patients in each group had American Spinal Injury Association impairment level B; 5 patients of group I and none of group II had cervical lesions while 6 patients of group I and all 9 of group II had thoracic lesions. Only 2 patients in group I presented clearly periodic leg movements during sleep and PLMS index >15/h. Electroencephalographic delta, alpha and beta bands around leg movements increased clearly in group II while the changes in group I were very limited or absent.
  
  
  CONCLUSIONS
  Leg movements during sleep are recorded in spinal cord injury patients with completely absent volitional activity in their lower limb but they show clear periodicity only in a small subgroup of them.
  
  
  CONCLUSIONS
  The disconnection from higher nervous structures, in patients with spinal cord injury might favor the appearance of leg movements due to the activity of spinal generators not inhibited by higher influences; correlated autonomic and electroencephalographic changes can be absent. This motor activity might assume the periodic character when a genetic predisposition is present.
authors.affiliation: Sleep Research Centre, Department of Neurology I.C., Oasi Institute (IRCCS), Troina, Italy. Electronic address: rferri@oasi.en.it.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Ferri
authors.affiliation: Centre of Epilepsy Surgery "C. Munari", Centre of Sleep Medicine, Niguarda Hospital, Milan, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Proserpio
authors.affiliation: Sleep Research Centre, Department of Neurology I.C., Oasi Institute (IRCCS), Troina, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Rundo
authors.affiliation: Centre of Epilepsy Surgery "C. Munari", Centre of Sleep Medicine, Niguarda Hospital, Milan, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lanza
authors.affiliation: Centre of Epilepsy Surgery "C. Munari", Centre of Sleep Medicine, Niguarda Hospital, Milan, Italy.
authors.forename: Katrina
authors.initials: K
authors.lastname: Sambusida
authors.affiliation: Centre of Epilepsy Surgery "C. Munari", Centre of Sleep Medicine, Niguarda Hospital, Milan, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Redaelli
authors.affiliation: Institute of Molecular Bioimaging and Physiology, Consiglio Nazionale delle Ricerche, Genoa, Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: De Carli
authors.affiliation: Centre of Epilepsy Surgery "C. Munari", Centre of Sleep Medicine, Niguarda Hospital, Milan, Italy.
authors.forename: Lino
authors.initials: L
authors.lastname: Nobili
mesh_terms: D000208:Acute Disease; D000328:Adult; D002574:Cervical Vertebrae; D004569:Electroencephalography / Q000379:methods; D005260:Female; D006801:Humans; D007866:Leg / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D010507:Periodicity; D017286:Polysomnography / Q000379:methods; D012890:Sleep / Q000502:physiology; D013119:Spinal Cord Injuries / Q000175:diagnosis / Q000503:physiopathology*; D013904:Thoracic Vertebrae
keywords: Heart rate; Leg movements; Periodicity index; Sleep; Spectral EEG analysis; Spinal cord injury