title: Effects of multiple injections of hypertonic dextrose in the rabbit carpal tunnel: a potential model of carpal tunnel syndrome development.
abstract: BACKGROUND
  This study investigated the effects of a series of four hypertonic dextrose injections on the subsynovial connective tissue (SSCT) and median nerve within the carpal tunnel of a rabbit model.
  
  
  METHODS
  Twenty New Zealand white rabbits were used. One forepaw carpal tunnel was randomly injected with 0.1 ml of 10 % dextrose solution. The contralateral forepaw was injected with a similar amount of saline. This injection was made once per week for 4 weeks. The animals were killed at 16 weeks after the initial injection and were evaluated by electrophysiology (EP), SSCT mechanical testing, and histology.
  
  
  RESULTS
  Mechanical testing revealed significantly greater ultimate load and energy absorption in the dextrose injection group compared to the saline injection group (P < 0.05). Histological evaluation revealed SSCT fibrosis and thickening and edema in the median nerve bundles in the dextrose injection group. There was a prolongation in the latency of the EP test in the dextrose injection group (P = 0.08).
  
  
  CONCLUSIONS
  Previous studies had shown that one or two injections of 10 % dextrose could induce moderate SSCT fibrosis and mild EP changes without nerve histology changes. In this study, we have shown that higher doses create more severe fibrosis and, most importantly, more severe neuropathy, suggesting a dose-response effect, and confirming this as a potentially useful animal model for researching the etiology and treatment of carpal tunnel syndrome.
authors.affiliation: Tendon and Soft Tissue Biology Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA ; Orthopedic Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Yoshii
authors.affiliation: Tendon and Soft Tissue Biology Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA ; Orthopedic Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA.
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, MN 55905 USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Schmelzer
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, MN 55905 USA.
authors.forename: Phillip A
authors.initials: PA
authors.lastname: Low
authors.affiliation: Tendon and Soft Tissue Biology Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA ; Orthopedic Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA.
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
authors.affiliation: Tendon and Soft Tissue Biology Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA ; Orthopedic Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Amadio
keywords: Carpal tunnel syndrome; Hypertonic dextrose; Rabbit; Subsynovial connective tissue