title: Spinal reflex activity: a marker for neuronal functionality after spinal cord injury.
abstract: BACKGROUND
  Alterations in the function of spinal neuronal circuits underlying locomotion after a spinal cord injury (SCI) are associated with changes in the behavior of spinal reflexes (SRs) in both rats and humans. In healthy subjects, the SR consists of a dominant early reflex component, whereas in chronic, severely affected SCI subjects, a later component dominates.
  
  
  OBJECTIVE
  The aim of this study was to investigate the relationship between SR behavior and walking ability in para-/tetraplegic subjects.
  
  
  METHODS
  The SR was evoked by nonnoxious tibial nerve stimulation. Walking ability was assessed by functional tests and questionnaires.
  
  
  RESULTS
  There was a correlation between walking ability and SR behavior in chronic SCI: Severely affected SCI subjects unable to walk showed dominant late SR components, whereas in ambulatory SCI subjects an early SR component dominated. A functional training with an improvement of locomotor ability was accompanied by both a shift from a dominant to a smaller late and the appearance of an early SR component.
  
  
  CONCLUSIONS
  Our findings indicate that SR can serve as a marker for the locomotor ability of SCI subjects. Neuronal plasticity exploited by a functional training is reflected in both an improvement of locomotor ability and a change in balance of SR components toward the early SR component.
authors.affiliation: Balgrist University Hospital, University of Zurich, Zurich, Switzerland. mhubli@paralab.balgrist.ch
authors.forename: Michèle
authors.initials: M
authors.lastname: Hubli
authors.forename: Volker
authors.initials: V
authors.lastname: Dietz
authors.forename: Marc
authors.initials: M
authors.lastname: Bolliger
mesh_terms: D000328:Adult; D000368:Aged; D004558:Electric Stimulation; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012018:Reflex / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000473:pathology* / Q000503:physiopathology* / Q000534:rehabilitation*; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires; D013979:Tibial Nerve / Q000503:physiopathology; D016138:Walking / Q000502:physiology; D055815:Young Adult