title: Daily Electrical Muscle Stimulation Enhances Functional Recovery Following Nerve Transection and Repair in Rats.
abstract: BACKGROUND
  Incomplete recovery following surgical reconstruction of damaged peripheral nerves is common. Electrical muscle stimulation (EMS) to improve functional outcomes has not been effective in previous studies.
  
  
  OBJECTIVE
  To evaluate the efficacy of a new, clinically translatable EMS paradigm over a 3-month period following nerve transection and immediate repair.
  
  
  METHODS
  Rats were divided into 6 groups based on treatment (EMS or no treatment) and duration (1, 2, or 3 months). A tibial nerve transection injury was immediately repaired with 2 epineurial sutures. The right gastrocnemius muscle in all rats was implanted with intramuscular electrodes. In the EMS group, the muscle was electrically stimulated with 600 contractions per day, 5 days a week. Terminal measurements were made after 1, 2, or 3 months. Rats in the 3-month group were assessed weekly using skilled and overground locomotion tests. Neuromuscular junction reinnervation patterns were also examined.
  
  
  RESULTS
  Muscles that received daily EMS had significantly greater numbers of reinnervated motor units with smaller average motor unit sizes. The majority of muscle endplates were reinnervated by a single axon arising from a nerve trunk with significantly fewer numbers of terminal sprouts in the EMS group, the numbers being small. Muscle mass and force were unchanged but EMS improved behavioral outcomes.
  
  
  CONCLUSIONS
  Our results demonstrated that EMS using a moderate stimulation paradigm immediately following nerve transection and repair enhances electrophysiological and behavioral recovery.
authors.affiliation: The Hospital for Sick Children, Toronto, Ontario, Canada mike.willand@gmail.com.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Willand
authors.affiliation: The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Cameron D
authors.initials: CD
authors.lastname: Chiang
authors.affiliation: The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Zhang
authors.affiliation: The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Stephen W P
authors.initials: SW
authors.lastname: Kemp
authors.affiliation: The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Gregory H
authors.initials: GH
authors.lastname: Borschel
authors.affiliation: The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Tessa
authors.initials: T
authors.lastname: Gordon
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004599:Electric Stimulation Therapy / Q000379:methods*; D004576:Electromyography; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008124:Locomotion / Q000502:physiology; D008297:Male; D009046:Motor Neurons / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology* / Q000628:therapy*; D011597:Psychomotor Performance; D051381:Rats; D055647:Rats, Transgenic; D020127:Recovery of Function / Q000502:physiology*; D013997:Time Factors
chemical_list: D049452:Green Fluorescent Proteins
keywords: electrical muscle stimulation; electromyography; muscle denervation; muscular atrophy; peripheral nerve injuries; tibial nerve