title: Knot security in simple sliding knots and its relationship to rotator cuff repair: how secure must the knot be?
abstract: We sought to determine which simple sliding knot configurations would have adequate strength for rotator cuff repair. Four knot configurations were tied with both No. 1 polydioxanone suture and No. 2 Ethibond suture (Ethicon, Somerville, NJ) using 3 different tying techniques: hand-tie, standard knot pusher, and cannulated double-diameter knot pusher. The knots were then tested to failure on a materials testing system. The weakest standard knot configuration was S=S=S=S. The other 3 knot configurations (S//S//S//S, SxSxSxS, and S//xS//xS//xS) generally failed in the 35 to 50 N range. Ultimate strength in this range can be shown to be adequate to withstand, without suture failure, a maximal contraction of a repaired rotator cuff tear within the rotator crescent, assuming certain conditions are met (suture anchors placed 1 cm apart, 2 sutures per anchor). More complex knots are not necessary for adequate knot security. However, the same configuration with only 1 suture per anchor will not be strong enough because the suture will fail under maximum physiological load. This study shows that we can predict the adequacy of a given knot configuration under maximum physiological loading conditions.
authors.affiliation: San Antonio Orthopaedic Group, The University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: S S
authors.initials: SS
authors.lastname: Burkhart
authors.forename: M A
authors.initials: MA
authors.lastname: Wirth
authors.forename: M
authors.initials: M
authors.lastname: Simonich
authors.forename: D
authors.initials: D
authors.lastname: Salem
authors.forename: D
authors.initials: D
authors.lastname: Lanctot
authors.forename: K
authors.initials: K
authors.lastname: Athanasiou
mesh_terms: D001182:Arthroscopy; D006801:Humans; D016687:Polydioxanone; D011093:Polyethylene Terephthalates; D017006:Rotator Cuff / Q000601:surgery*; D013314:Stress, Mechanical; D013536:Suture Techniques; D013537:Sutures; D013718:Tensile Strength
chemical_list: C014534:Ethibond; D011093:Polyethylene Terephthalates; D016687:Polydioxanone