title: Rotator cuff repair with a tendon-fibrocartilage-bone composite bridging patch.
abstract: BACKGROUND
  To compare the mechanical performance of a rotator cuff repaired with a novel tendon-fibrocartilage-bone composite bridging patch vs the traditional Mason-Allen repair in an in vitro canine model.
  
  
  METHODS
  Twenty shoulders and 10 bridging patches from patellar tendon were harvested. The patches were trimmed and sliced into 2 layers. An infraspinatus tendon tear was created in each shoulder. Modified Mason-Allen sutures were used to repair the infraspinatus tendon to the greater tuberosity, with or without the bridging patch (bridging patch group and controls, respectively). Shoulders were loaded to failure under displacement control at a rate of 0.5mm/s.
  
  
  RESULTS
  The ultimate tensile load was significantly higher in the bridging patch group than control (mean [SD], 365.46 [36.45] vs 272.79 [48.88] N; P<.001). Stiffness at the greater tuberosity repair site and the patch-infraspinatus tendon repair site was significantly higher than the control repair site (93.96 [27.72] vs 42.62 [17.48] N/mm P<.001; 65.94 [24.51] vs 42.62 [17.48] N/mm P=.02, respectively).
  
  
  CONCLUSIONS
  The tendon-fibrocartilage-bone composite bridging patch achieved higher ultimate tensile load and stiffness at the patch-greater tuberosity repair site compared with traditional repair in a canine model. This composite tissue transforms the traditional tendon-to-bone healing interface (with dissimilar tissues) into a pair of bone-to-bone and tendon-to-tendon interfaces, which may improve healing quality and reduce retear rate.
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA; Trauma Center, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200080, China.
authors.forename: Xiaoxi
authors.initials: X
authors.lastname: Ji
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Qingshan
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Thoreson
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Jin
authors.initials: J
authors.lastname: Qu
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Amadio
authors.affiliation: Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Scott P
authors.initials: SP
authors.lastname: Steinmann
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA. Electronic address: zhaoc@mayo.edu.
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Zhao
mesh_terms: D064591:Allografts; D000818:Animals; D001696:Biomechanical Phenomena; D004285:Dogs; D051445:Fibrocartilage / Q000637:transplantation*; D066298:In Vitro Techniques; D023421:Models, Animal; D019637:Orthopedic Procedures / Q000379:methods*; D010329:Patella / Q000637:transplantation*; D017847:Patellar Ligament / Q000637:transplantation*; D017006:Rotator Cuff / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D013537:Sutures; D013718:Tensile Strength
keywords: Bridging patch; Rotator cuff repair; Tendon-to-bone healing