title: Biomechanical analysis of a double-loaded glenoid anchor configuration: can fewer anchors provide equivalent fixation?
abstract: BACKGROUND
  Bankart repair with multiple anchor holes concentrated in the anterior-inferior glenoid may contribute to glenoid weakening and potentially may induce glenoid failure.
  
  
  OBJECTIVE
  To compare the biomechanical strength of a Bankart repair construct that used 3 single-loaded suture anchors versus a repair construct that used 2 double-loaded suture anchors.
  
  
  METHODS
  Comparative laboratory study.
  
  
  METHODS
  A standard Bankart lesion was created in 18 human cadaveric shoulders (9 matched pairs). Within each matched pair, 1 repair construct used 3 single-loaded anchors, whereas the other used 2 double-loaded suture anchors. Measured outcomes (load, stiffness, and energy absorbed) were recorded at failure and at 2 mm of labral displacement. Constructs were loaded to failure with a materials testing device that had differential variable reluctance transducers for displacement measurements.
  
  
  RESULTS
  The double-loaded anchor construct had a significantly higher ultimate tensile load (944 ± 231 vs 784 ± 287 N; P = .03). For the other measures (load at 2 mm of displacement, energy absorbed at failure and at 2 mm of displacement and stiffness), there were no significant differences between tested constructs.
  
  
  CONCLUSIONS
  A Bankart repair construct that used 2 double-loaded anchors was either superior to or equal to a repair construct that used 3 single-loaded anchors in all measured outcomes.
  
  
  CONCLUSIONS
  Using 2 double-loaded suture anchors for a Bankart repair may limit anchor holes in the glenoid and reduce the risk of postsurgical glenoid fracture while providing a stable repair construct.
authors.affiliation: Department of Orthopaedic Surgery, University of North Carolina-Chapel Hill, 27599, USA. ganesh_kamath@med.unc.edu
authors.forename: Ganesh V
authors.initials: GV
authors.lastname: Kamath
authors.forename: Stephen
authors.initials: S
authors.lastname: Hoover
authors.forename: R Alexander
authors.initials: RA
authors.lastname: Creighton
authors.forename: Paul
authors.initials: P
authors.lastname: Weinhold
authors.forename: Aaron
authors.initials: A
authors.lastname: Barrow
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Spang
mesh_terms: D001696:Biomechanical Phenomena; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D008875:Middle Aged; D012785:Shoulder Joint / Q000601:surgery*; D013536:Suture Techniques