title: Development of an Arthroscopic Joint Capsule Injury Model in the Canine Shoulder.
abstract: BACKGROUND
  The natural history of rotator cuff tears can be unfavorable as patients develop fatty infiltration and muscle atrophy that is often associated with a loss of muscle strength and shoulder function. To facilitate study of possible biologic mechanisms involved in early degenerative changes to rotator cuff muscle and tendon tissues, the objective of this study was to develop a joint capsule injury model in the canine shoulder using arthroscopy.
  
  
  METHODS
  Arthroscopic surgical methods for performing a posterior joint capsulectomy in the canine shoulder were first defined in cadavers. Subsequently, one canine subject underwent bilateral shoulder joint capsulectomy using arthroscopy, arthroscopic surveillance at 2, 4 and 8 weeks, and gross and histologic examination of the joint at 10 weeks.
  
  
  RESULTS
  The canine subject was weight-bearing within eight hours after index and follow-up surgeries and had no significant soft tissue swelling of the shoulder girdle or gross lameness. Chronic synovitis and macroscopic and microscopic evidence of pathologic changes to the rotator cuff bony insertions, tendons, myotendinous junctions and muscles were observed.
  
  
  CONCLUSIONS
  This study demonstrates feasibility and proof-of-concept for a joint capsule injury model in the canine shoulder. Future work is needed to define the observed pathologic changes and their role in the progression of rotator cuff disease. Ultimately, better understanding of the biologic mechanisms of early progression of rotator cuff disease may lead to clinical interventions to halt or slow this process and avoid the more advanced and often irreversible conditions of large tendon tears with muscle fatty atrophy.
authors.affiliation: Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: David
authors.initials: D
authors.lastname: Kovacevic
authors.affiliation: Department of Biomedical Engineering and the Orthopaedic Research Center, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Baker
authors.affiliation: Department of Pathology, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Staugaitis
authors.affiliation: Department of Orthopaedic Surgery, Chonnam National University College of Medicine, Gwangju, Republic of Korea.
authors.forename: Myung-Sun
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Eric T
authors.initials: ET
authors.lastname: Ricchetti
authors.affiliation: Department of Biomedical Engineering and the Orthopaedic Research Center, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Derwin
mesh_terms: D000818:Animals; D001182:Arthroscopy; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D017746:Joint Capsule / Q000293:injuries*; D007592:Joint Diseases / Q000473:pathology*; D012785:Shoulder Joint / Q000473:pathology*