title: Interference screw versus suture anchor fixation for subpectoral tenodesis of the proximal biceps tendon: a cadaveric study.
abstract: OBJECTIVE
  The purpose of this study was to compare the biomechanical properties of 2 fixation methods for subpectoral proximal biceps tenodesis.
  
  
  METHODS
  In 9 matched pairs of cadaveric shoulders, an open subpectoral tenodesis was performed 1 cm proximal to the inferior border of the pectoralis major tendon by use of either an 8 x 12-mm Bio-Tenodesis screw (Arthrex, Naples, FL) with No. 2 FiberWire sutures (Arthrex) or a 5.5-mm Bio-Corkscrew double-loaded suture anchor (Arthrex) with No. 2 FiberWire sutures. The specimens were dissected and mounted in a material testing machine. Cyclic loading (20 to 60 N, 100 cycles, 0.5 mm/s, 5-N preload) was performed, followed by an unloaded 30-minute rest, a 5-N preload, and a load-to-failure protocol (1.25 mm/s) with a 100-lb load cell. Ultimate load (in Newtons), stiffness (in Newtons per millimeter), and modes of failure were recorded. Data were analyzed by use of paired t tests and Wilcoxon signed rank tests.
  
  
  RESULTS
  Proximal biceps tenodeses with Bio-Tenodesis screws had a significantly higher mean load to failure (169.6 +/- 50.5 N; range, 99.6 to 244.7 N) than those with Bio-Corkscrew suture anchors (68.5 +/- 33.0 N; range, 24.2 to 119.4 N) (P = .002). Bio-Tenodesis screws also had a significantly higher stiffness (34.1 +/- 9.0 N/mm; range, 20.6 to 48.9 N/mm) than Bio-Corkscrews (19.3 +/- 10.5; range, 5.9 to 32.9 N/mm) (P = .038).
  
  
  CONCLUSIONS
  In this cadaveric study the Bio-Tenodesis screw showed a statistically significantly higher load to failure and significantly higher stiffness than the Bio-Corkscrew anchor when used for tenodesis of the proximal biceps tendon in a subpectoral location.
  
  
  CONCLUSIONS
  Biomechanical comparison of these 2 fixation techniques provides information on stiffness and load to failure of alternate fixation methods.
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia, Charlottesville, Virginia,USA.
authors.forename: S Raymond
authors.initials: SR
authors.lastname: Golish
authors.forename: Paul E
authors.initials: PE
authors.lastname: Caldwell
authors.forename: Mark D
authors.initials: MD
authors.lastname: Miller
authors.forename: Naveen
authors.initials: N
authors.lastname: Singanamala
authors.forename: Anil S
authors.initials: AS
authors.lastname: Ranawat
authors.forename: Gehron
authors.initials: G
authors.lastname: Treme
authors.forename: Sara E
authors.initials: SE
authors.lastname: Pearson
authors.forename: Ryan
authors.initials: R
authors.lastname: Costic
authors.forename: Jon K
authors.initials: JK
authors.lastname: Sekiya
mesh_terms: D020341:Absorbable Implants; D001696:Biomechanical Phenomena; D001863:Bone Screws; D002102:Cadaver; D006801:Humans; D006811:Humerus / Q000601:surgery; D018482:Muscle, Skeletal / Q000502:physiology*; D009984:Orthopedic Fixation Devices; D017006:Rotator Cuff / Q000601:surgery; D013537:Sutures; D013708:Tendon Injuries / Q000601:surgery*; D013718:Tensile Strength