title: Biomechanical evaluation of transosseous rotator cuff repair: do anchors really matter?
abstract: BACKGROUND
  Suture anchor fixation has become the preferred method for arthroscopic repairs of rotator cuff tears. Recently, newer arthroscopic repair techniques including transosseous-equivalent repairs with anchors or arthroscopic transosseous suture passage have been developed.
  
  
  OBJECTIVE
  To compare the initial biomechanical performance including ultimate load to failure and localized cyclic elongation between transosseous-equivalent repair with anchors (TOE), traditional transosseous repair with a curved bone tunnel (TO), and an arthroscopic transosseous repair technique utilizing a simple (AT) or X-box suture configuration (ATX).
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Twenty-eight human cadaveric shoulders were dissected to create an isolated supraspinatus tear and randomized into 1 of 4 repair groups (TOE, TO, AT, ATX). Tensile testing was conducted to simulate the anatomic position of the supraspinatus with the arm in 60° of abduction and involved an initial preload, cyclic loading, and pull to failure. Localized elongation during testing was measured using optical tracking. Data were statistically assessed using analysis of variance with a Tukey post hoc test for multiple comparisons.
  
  
  RESULTS
  The TOE repair demonstrated a significantly higher mean ± SD failure load (558.4 ± 122.9 N) compared with the TO (325.3 ± 79.9 N), AT (291.7 ± 57.9 N), and ATX (388.5 ± 92.6 N) repairs (P < .05). There was also a significantly larger amount of first-cycle excursion in the AT group (8.19 ± 1.85 mm) compared with the TOE group (5.10 ± 0.89 mm). There was no significant difference between repair groups in stiffness during maximum load to failure or in normalized cyclic elongation. Failure modes were as follows: TOE, tendon (n = 4) and bone (n = 3); TO, suture (n = 6) and bone (n = 1); AT, tendon (n = 2) and bone (n = 3) and suture (n = 1); ATX, tendon (n = 7).
  
  
  CONCLUSIONS
  This study demonstrates that anchorless repair techniques using transosseous sutures result in significantly lower failure loads than a repair model utilizing anchors in a TOE construct.
  
  
  CONCLUSIONS
  Suture anchor repair appears to offer superior biomechanical properties to transosseous repairs regardless of tunnel or suture configuration.
authors.affiliation: Rush University Medical Center, 1725 West Harrison Street, Suite 1063, Chicago, IL 60612, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Salata
authors.forename: Seth L
authors.initials: SL
authors.lastname: Sherman
authors.forename: Emery C
authors.initials: EC
authors.lastname: Lin
authors.forename: Robert A
authors.initials: RA
authors.lastname: Sershon
authors.forename: Aman
authors.initials: A
authors.lastname: Gupta
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Shewman
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Wang
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Cole
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Romeo
authors.forename: Nikhil N
authors.initials: NN
authors.lastname: Verma
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001182:Arthroscopy; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017006:Rotator Cuff / Q000503:physiopathology / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D012782:Shoulder / Q000503:physiopathology; D053441:Suture Anchors; D013536:Suture Techniques; D013708:Tendon Injuries / Q000503:physiopathology / Q000601:surgery*