title: Biochemical, histologic, and biomechanical characterization of native and decellularized flexor tendon specimens harvested from the pelvic limbs of orthopedically normal dogs.
abstract: OBJECTIVE
  To evaluate the biochemical and biomechanical properties of native and decellularized superficial digital flexor tendons (SDFTs) and deep digital flexor tendons (DDFTs) harvested from the pelvic limbs of orthopedically normal dogs.
  
  
  METHODS
  22 commercially supplied tendon specimens (10 SDFT and 12 DDFT) harvested from the pelvic limbs of 13 canine cadavers.
  
  
  METHODS
  DNA, glycosaminoglycan, collagen, and protein content were measured to biochemically compare native and decellularized SDFT and DDFT specimens. Mechanical testing was performed on 4 groups consisting of native tendons (5 SDFTs and 6 DDFTs) and decellularized tendons (5 SDFTs and 6 DDFTs). All tendons were preconditioned, and tension was applied to failure at 0.5 mm/s. Failure mode was video recorded for each tendon. Load-deformation and stress-strain curves were generated; calculations were performed to determine the Young modulus and stiffness. Biochemical and biomechanical data were statistically compared by use of the Wilcoxon rank sum test.
  
  
  RESULTS
  Decellularized SDFT and DDFT specimens had significantly less DNA content than did native tendons. No significant differences were identified between native and decellularized specimens with respect to glycosaminoglycan, collagen, or protein content. Biomechanical comparison yielded no significant intra- or intergroup differences. All DDFT constructs failed at the tendon-clamp interface, whereas nearly half (4/10) of the SDFT constructs failed at midsubstance.
  
  
  CONCLUSIONS
  Decellularized commercial canine SDFT and DDFT specimens had similar biomechanical properties, compared with each other and with native tendons. The decellularization process significantly decreased DNA content while minimizing loss of extracellular matrix components. Decellularized canine flexor tendons may provide suitable, biocompatible graft scaffolds for bioengineering applications such as tendon or ligament repair.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Balogh
authors.forename: Jeffery J
authors.initials: JJ
authors.lastname: Biskup
authors.forename: M Gerard
authors.initials: MG
authors.lastname: O'Sullivan
authors.forename: Ruth M
authors.initials: RM
authors.lastname: Scott
authors.forename: Donna
authors.initials: D
authors.lastname: Groschen
authors.forename: Richard B
authors.initials: RB
authors.lastname: Evans
authors.forename: Michael G
authors.initials: MG
authors.lastname: Conzemius
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002102:Cadaver; D003094:Collagen / Q000032:analysis; D004285:Dogs / Q000033:anatomy & histology*; D055119:Elastic Modulus; D005109:Extracellular Matrix; D006025:Glycosaminoglycans / Q000032:analysis; D006614:Hindlimb / Q000033:anatomy & histology*; D016059:Range of Motion, Articular; D012016:Reference Values; D013710:Tendons / Q000033:anatomy & histology*
chemical_list: D006025:Glycosaminoglycans; D003094:Collagen