title: Arthroscopic suture anchor capsulorrhaphy versus labral-based suture capsulorrhaphy in a cadaveric model.
abstract: OBJECTIVE
  The purpose of this study was to establish whether suture anchor capsulorrhaphy (SAC) is biomechanically superior to suture capsulorrhaphy (SC) in the management of recurrent anterior shoulder instability without a labral avulsion.
  
  
  METHODS
  Twelve matched pairs of shoulders were randomized to either SC or SAC. Specimens were mounted in 60° of abduction and 90° of external rotation. Testing was conducted on an MTS servohydraulic load testing device (MTS, Eden Prairie, MN). A compressive load of 22 N was applied, followed by a 2-N anterior and posterior force to establish a 0 point. Translation with 10-N anterior and posterior loads was recorded for baseline laxity measurement. Arthroscopic capsulorrhaphy was performed with either 3 solitary sutures or 3 suture anchors. Specimens were remounted and returned to the 0 point. Translation was measured with 10-N anterior and posterior loads to determine reduction in translation. Specimens were then loaded to failure to the 0 point at a rate of 0.1 mm/s.
  
  
  RESULTS
  Load to failure was significantly greater (P = .02) in the SC group (13.6 ± 1.0 N) versus the SAC group (20.5 ± 2.8 N). No differences were found between SC (2.7 ± 0.7 mm) and SAC (2.3 ± 0.6 mm) when we compared reduction of anterior translation with a 10-N load. The percent reduction of anterior displacement with a 10-N load was similar for the SC (49.9%) and SAC (49.6%) groups. The dominant mode of failure in the study was suture pull-through of the capsular tissue.
  
  
  CONCLUSIONS
  Our study indicates that labral-based SC and SAC similarly reduce anterior glenohumeral translation at low loading conditions. Load-to-failure studies indicate that SAC exhibits significantly greater resistance to translation at higher loading conditions. Our study suggests that the use of a suture anchor when one is performing a capsulorrhaphy may provide biomechanical advantage at high loading conditions.
  
  
  CONCLUSIONS
  Our study suggests that when one is performing capsulorrhaphy, the use of a suture anchor may provide biomechanical advantages at high loading conditions.
authors.affiliation: Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Gillis
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Donaldson
authors.forename: Hyunchul
authors.initials: H
authors.lastname: Kim
authors.forename: James M
authors.initials: JM
authors.lastname: Love
authors.forename: James C
authors.initials: JC
authors.lastname: Dreese
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001182:Arthroscopy / Q000379:methods*; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000601:surgery; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012785:Shoulder Joint / Q000503:physiopathology / Q000601:surgery*; D053441:Suture Anchors; D013536:Suture Techniques; D016474:Weight-Bearing