title: Ulnar collateral ligament reconstruction using bisuspensory fixation: a biomechanical comparison with the docking technique.
abstract: BACKGROUND
  Many ulnar collateral ligament (UCL) reconstruction techniques have been created and biomechanically tested. Single-bundle reconstructions aim to re-create the important anterior bundle of the UCL. To date, no technique has utilized suspensory fixation on the ulnar and humeral sides to create a single-bundle reconstruction.
  
  
  OBJECTIVE
  The bisuspensory technique will restore valgus laxity to its native state, with comparable load-to-failure characteristics to the docking technique.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Six matched pairs of fresh-frozen cadaveric elbows were randomized to undergo UCL reconstruction using either the docking technique or a novel single-bundle bisuspensory technique. Valgus laxity and rotation measurements were quantified using a MicroScribe 3DLX digitizer at various flexion angles for the native ligament, transected ligament, and 1 of the 2 tested reconstructed ligaments. Laxity testing was performed from maximum extension to 120° of flexion. Each reconstruction was then tested to failure, and the method of failure was recorded.
  
  
  RESULTS
  Valgus laxity was restored to the intact state at all degrees of elbow flexion for both the docking and bisuspensory techniques. In load-to-failure testing, there was no significant difference with regard to stiffness, ultimate torque, ultimate torque angle, energy absorbed, and applied moment to reach 10° of valgus. Yield torques for the bisuspensory and docking reconstructions were 18.7 ± 7.8 N·m and 18.6 ± 4.4 N·m, respectively (P = .95). The ultimate torque for the bisuspensory technique measured 26.5 ± 9.2 N·m and for the docking technique measured 25.1 ± 7.1 N·m (P = .78).
  
  
  CONCLUSIONS
  The bisuspensory fixation technique, a reproducible single-bundle reconstruction, was able to restore valgus laxity to the native state, with similar load-to-failure characteristics as the docking technique.
  
  
  CONCLUSIONS
  This reconstruction technique could be considered in a clinical setting as a primary method of UCL reconstruction or as a backup fixation method should intraoperative complications occur.
authors.affiliation: Congress Medical Associates Inc, 800 South Raymond Avenue, Pasadena, CA 91105, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Jackson
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Adamson
authors.forename: Alexander
authors.initials: A
authors.lastname: Peterson
authors.forename: John
authors.initials: J
authors.lastname: Patton
authors.forename: Michelle H
authors.initials: MH
authors.lastname: McGarry
authors.forename: Thay Q
authors.initials: TQ
authors.lastname: Lee
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D002102:Cadaver; D017885:Collateral Ligaments / Q000293:injuries / Q000601:surgery*; D004551:Elbow Joint / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D011897:Random Allocation; D012399:Rotation; D013710:Tendons / Q000637:transplantation; D019415:Torque; D000092464:Elbow Injuries
keywords: Tommy John surgery; biomechanics; docking; elbow; ulnar collateral ligament