The effect of number of throws on knot security with nonidentical sliding knots

Objective The study was undertaken to test the integrity of nonidentical sliding knots made with 3 throws compared with those made with 6 throws with monofilament and braided absorbable suture. Study design The 3 throw nonidentical sliding knot was compared with the 6 throw nonidentical sliding knot in 4 different suture groups. The groups were 0-0 polydioxanone, 2-0 polydioxanone, 0-0 polyglactin 910, and 2-0 polyglactin 910. Knots were tested to failure with a tensiometer. The proportion of 3 throw knots becoming untied was compared with the 6 throw knot within each group. Ultimate load required to break tied knots within each suture group was also evaluated. Results The 3 throw knots had very high rates of knot failure and untied significantly more often than the 6 throw knots. Conclusion The 6 throw nonidentical sliding knot demonstrates superior knot integrity compared with the 3 throw knot with both monofilament and braided absorbable suture.