Ss. Burkhart et al., Knot security in simple sliding knots and its relationship to rotator cuffrepair: How secure must the knot be?, ARTHROSCOPY, 16(2), 2000, pp. 202-207
We sought to determine which simple sliding knot configurations would have
adequate strength for rotator cuff repair. Four knot configurations were ti
ed with both No. 1 polydioxanone suture and No. 2 Ethibond suture (Ethicon,
Somerville, NJ) using 3 different tying techniques: hand-tie, standard kno
t pusher, and cannulated double-diameter knot pusher. The knots were then t
ested to failure on a materials testing system. The weakest standard knot c
onfiguration was S=S=S=S. The other 3 knot configurations (S//S//S//S, SxSx
SxS, 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 su
ture failure, a maximal contraction of a repaired rotator cuff tear within
the rotator crescent, assuming certain conditions are met (suture anchors p
laced 1 cm apart, 2 sutures per anchor). More complex knots are not necessa
ry for adequate knot security. However, the same configuration with only 1
suture per anchor will not be strong enough because the suture will fail un
der maximum physiological load. This study shows that we can predict the ad
equacy of a given knot configuration under maximum physiological loading co
nditions.