title: The effect of age on peripheral motor nerve function after crush injury in the rat.
abstract: OBJECTIVE
  To determine the ontogeny of functional recovery after peripheral nerve crush injury.
  
  
  METHODS
  Comparative study in rats of varying ages.
  
  
  METHODS
  Sixty-second crush injury was performed on the left posterior tibial nerve. Control animals underwent either nerve transection or sham procedure. Nerve function was evaluated 2, 4, and 8 weeks following injury by walking track analysis. Print length ratio (PLR), (ratio of normal right-sided print length to experimental left-sided print length), was used to evaluate functional recovery.
  
  
  RESULTS
  Two weeks after crush injury, adult rats experienced significantly greater functional impairment than both 4-day-old and 3-week-old animals (p < 0.05). Four weeks after injury, the difference in function between 4-day-old and adult rats and between 3-week-old and adult rats became insignificant. Complete recovery had been achieved by 8 weeks in all groups.
  
  
  CONCLUSIONS
  These results demonstrate faster functional recovery after nerve injury in immature rats than in adults.
authors.affiliation: Division of Pediatric Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: B M
authors.initials: BM
authors.lastname: Belin
authors.forename: D J
authors.initials: DJ
authors.lastname: Ball
authors.forename: J C
authors.initials: JC
authors.lastname: Langer
authors.forename: P M
authors.initials: PM
authors.lastname: Bridge
authors.forename: P K
authors.initials: PK
authors.lastname: Hagberg
authors.forename: S E
authors.initials: SE
authors.lastname: Mackinnon
mesh_terms: D000344:Afferent Pathways / Q000293:injuries* / Q000503:physiopathology; D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D003289:Convalescence; D004195:Disease Models, Animal; D009409:Nerve Crush / Q000009:adverse effects*; D009416:Nerve Regeneration; D059348:Peripheral Nerve Injuries; D010525:Peripheral Nerves / Q000503:physiopathology; D011897:Random Allocation; D051381:Rats; D011917:Rats, Inbred Lew; D016138:Walking / Q000502:physiology