title: Biceps detachment decreases joint damage in a rotator cuff tear rat model.
abstract: BACKGROUND
  Pathology in the long head of the biceps tendon often occurs in patients with rotator cuff tears. Arthroscopic tenotomy is the most common treatment. However, the role of the long head of the biceps at the shoulder and the consequences of surgical detachment on the remaining shoulder structures remain unknown.
  
  
  OBJECTIVE
  We hypothesized that detachment of the long head of the biceps, in the presence of supraspinatus and infraspinatus tears, would decrease shoulder function and decrease mechanical and histologic properties of both the subscapularis tendon and the glenoid articular cartilage.
  
  
  METHODS
  We detached the supraspinatus and infraspinatus or the supraspinatus, infraspinatus, and long head of the biceps after 4 weeks of overuse in a rat model. Animals were gradually returned to overuse activity after detachment. At 8 weeks, the subscapularis and glenoid cartilage biomechanical and histologic properties were evaluated and compared.
  
  
  RESULTS
  The supraspinatus, infraspinatus, and long head of the biceps group had a decreased change in braking and vertical force. [corrected]. This group also had an increased upper and lower subscapularis modulus but without any differences in glenoid cartilage modulus. Finally, this group had a significantly lower cell density in both the upper and lower subscapularis tendons, although cartilage histology was not different.
  
  
  CONCLUSIONS
  Detachment of the long head of the biceps tendon in the presence of a posterior-superior cuff tear resulted in improved shoulder function and less joint damage in this animal model.
  
  
  CONCLUSIONS
  This study provides evidence in an animal model that supports the use of tenotomy for the management of long head of the biceps pathology in the presence of a two-tendon cuff tear. However, long-term clinical trials are required.
authors: McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 36th Street and Hamilton Walk, Philadelphia, PA, 19104-6081, USA.
authors: Stephen J
authors: SJ
authors: Thomas
authors: Katherine E
authors: KE
authors: Reuther
authors: Jennica J
authors: JJ
authors: Tucker
authors: Joseph J
authors: JJ
authors: Sarver
authors: Sarah M
authors: SM
authors: Yannascoli
authors: Adam C
authors: AC
authors: Caro
authors: Pramod B
authors: PB
authors: Voleti
authors: Sarah I
authors: SI
authors: Rooney
authors: David L
authors: DL
authors: Glaser
authors: Louis J
authors: LJ
authors: Soslowsky
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002358:Cartilage, Articular / Q000293:injuries / Q000503:physiopathology / Q000601:surgery; D004195:Disease Models, Animal; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D017006:Rotator Cuff / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D000070599:Shoulder Injuries; D012785:Shoulder Joint / Q000503:physiopathology / Q000601:surgery*; D013708:Tendon Injuries / Q000503:physiopathology / Q000601:surgery*; D058971:Tenotomy / Q000379:methods*; D013997:Time Factors