title: Comparison of a novel bone-tendon allograft with a human dermis-derived patch for repair of chronic large rotator cuff tears using a canine model.
abstract: OBJECTIVE
  This study tested a bone-tendon allograft versus human dermis patch for reconstructing chronic rotator cuff repair by use of a canine model.
  
  
  METHODS
  Mature research dogs (N = 15) were used. Radiopaque wire was placed in the infraspinatus tendon (IST) before its transection. Three weeks later, radiographs showed IST retraction. Each dog then underwent 1 IST treatment: debridement (D), direct repair of IST to bone with a suture bridge and human dermis patch augmentation (GJ), or bone-tendon allograft (BT) reconstruction. Outcome measures included lameness grading, radiographs, and ultrasonographic assessment. Dogs were killed 6 months after surgery and both shoulders assessed biomechanically and histologically.
  
  
  RESULTS
  BT dogs were significantly (P = .01) less lame than the other groups. BT dogs had superior bone-tendon, tendon, and tendon-muscle integrity compared with D and GJ dogs. Biomechanical testing showed that the D group had significantly (P = .05) more elongation than the other groups whereas BT had stiffness and elongation characteristics that most closely matched normal controls. Radiographically, D and GJ dogs showed significantly more retraction than BT dogs (P = .003 and P = .045, respectively) Histologically, GJ dogs had lymphoplasmacytic infiltrates, tendon degeneration and hypocellularity, and poor tendon-bone integration. BT dogs showed complete incorporation of allograft bone into host bone, normal bone-tendon junctions, and well-integrated allograft tendon.
  
  
  CONCLUSIONS
  The bone-tendon allograft technique re-establishes a functional IST bone-tendon-muscle unit and maintains integrity of repair in this model.
  
  
  CONCLUSIONS
  Clinical trials using this bone-tendon allograft technique are warranted.
authors.affiliation: Department of Orthopaedic Surgery, University of Missouri, Columbia, Missouri 65212, USA. smithmj@health.missouri.edu
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Smith
authors.forename: James L
authors.initials: JL
authors.lastname: Cook
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kuroki
authors.forename: Prakash S
authors.initials: PS
authors.lastname: Jayabalan
authors.forename: Cristi R
authors.initials: CR
authors.lastname: Cook
authors.forename: Ferris M
authors.initials: FM
authors.lastname: Pfeiffer
authors.forename: Nicole P
authors.initials: NP
authors.lastname: Waters
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D001696:Biomechanical Phenomena; D016025:Bone Transplantation; D020405:Dermis / Q000637:transplantation*; D004285:Dogs; D006801:Humans; D019637:Orthopedic Procedures / Q000379:methods; D011859:Radiography; D017006:Rotator Cuff / Q000000981:diagnostic imaging / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D053441:Suture Anchors; D013710:Tendons / Q000637:transplantation*; D014184:Transplantation, Homologous
chemical_list: D001672:Biocompatible Materials