title: Loop securities of arthroscopic sliding-knot techniques when the suture loop is not evenly tensioned.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the loop security of arthroscopic sliding knots when tension is only applied to the post strand and not the loop strand.
  
  
  METHODS
  Six different locking sliding knots (Weston, Nicky, Roeder, SMC, San Diego, and Dines) were included. Loop securities were evaluated in 2 ways: with a conventional method (equal tension applied to the suture loop) and with a worst-case scenario (WCS) method (only the post strand of the suture loop was tensioned). Differences between test methods were evaluated for significance. To help assess the applicability of each test method, loop-security testing in a cadaveric shoulder was performed with 1 type of knot (SMC).
  
  
  RESULTS
  Loop securities with the conventional method versus the WCS method were as follows: 10.74 ± 4.20 N versus 6.90 ± 3.90 N for Weston, 21.25 ± 14.74 N versus 8.73 ± 3.35 N for Nicky, 26.14 ± 15.57 N versus 7.95 ± 4.23 N for Roeder, 42.67 ± 22.96 N versus 8.67 ± 4.33 N for SMC, 52.99 ± 21.36 N versus 18.25 ± 10.58 N for San Diego, and 89.27 ± 27.96 N versus 12.48 ± 3.40 N for Dines (P < .05 for each knot). All knots failed at significantly lower loads when the suture loop was not evenly tensioned. Cadaveric testing (SMC) resulted in a loop security of 5.53 ± 6.06 N, which was similar to the WCS setting.
  
  
  CONCLUSIONS
  The locking mechanism of the sliding knots is maintained when the suture loop is evenly tensioned at both post and non-post strands. When tension is not applied to the non-post strand side, the knots slide more easily and fail at lower loads than previously reported.
  
  
  CONCLUSIONS
  When surgeons tie locking sliding knots in single-row rotator cuff repair, they should be aware that the knots could fail at much lower loads than previously reported.
authors.affiliation: Department of Orthopaedic Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Sae Hoon
authors.initials: SH
authors.lastname: Kim
authors.forename: Diana
authors.initials: D
authors.lastname: Glaser
authors.forename: Josh
authors.initials: J
authors.lastname: Doan
authors.forename: Seok Won
authors.initials: SW
authors.lastname: Chung
authors.forename: Hye Yeon
authors.initials: HY
authors.lastname: Choi
authors.forename: Joo Han
authors.initials: JH
authors.lastname: Oh
authors.forename: Alan R
authors.initials: AR
authors.lastname: Hargens
mesh_terms: D000368:Aged; D001182:Arthroscopy / Q000379:methods*; D002102:Cadaver; D005260:Female; D006801:Humans; D008422:Materials Testing; D017006:Rotator Cuff / Q000601:surgery*; D013536:Suture Techniques; D013537:Sutures; D013710:Tendons / Q000601:surgery; D016474:Weight-Bearing