title: Tendon injury produces changes in SSCT and nerve physiology similar to carpal tunnel syndrome in an in vivo rabbit model.
abstract: BACKGROUND
  The etiology of carpal tunnel syndrome (CTS) remains idiopathic in many cases. Noninflammatory fibrosis of the subsynovial connective tissue (SSCT) within the carpal tunnel is common in CTS, and some clinicians have hypothesized that this fibrosis might be a cause rather than an effect of CTS. An animal model in which to test this hypothesis would be useful. The principal objective of this study was to investigate the effect of a surgical injury on SSCT fibrosis and median nerve function within the carpal tunnel in an in vivo rabbit model.
  
  
  METHODS
  Rabbits were sacrificed 12 weeks after surgery and were evaluated by mechanical testing, histology, transmission and scanning electron microscopy, and electrophysiology.
  
  
  RESULTS
  SSCT fibroblast density (p < 0.0001) and collagen fiber size (p = 0.0004) were significantly higher, and the median nerve distal motor amplitude was significantly lower (p = 0.0018), in the tendon injury group SSCT than in either the sham or control groups.
  
  
  CONCLUSIONS
  Our findings are similar to those seen in patients with carpal tunnel syndrome and suggest that the tendon injury procedure may be the basis of a new animal model of SSCT injury and, possibly, CTS.
authors.affiliation: Orthopedic Biomechanics Laboratory, Department of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA.
authors.forename: Tamami
authors.initials: T
authors.lastname: Moriya
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Zhao
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Cha
authors.forename: James D
authors.initials: JD
authors.lastname: Schmelzer
authors.forename: Phillip A
authors.initials: PA
authors.lastname: Low
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
authors.forename: Peter C
authors.initials: PC
authors.lastname: Amadio