Mechanical performance of knots using braided and monofilament absorbable sutures.

Abstract

The study was undertaken to test the integrity of various flat and sliding knots with the use of braided and monofilament absorbable sutures. There were four study groups, each of which consisted of a single suture type and size, with five different knots. Each combination was tested 10 times for a total of 200 experiments. The suture types used were 0-0 and 2-0 Glycomer 631 (Biosyn) and 0-0 and 2-0 coated Lactomer (Polysorb). Knots tested were the square knots, surgeon's knots, modified granny flat knots, and modified identical and nonidentical sliding knots. Knots were tested to failure with a tensiometer. We compared the proportion of knots becoming untied within each group and the ultimate load required to break tied knots. In the 0-0 and 2-0 Lactomer groups, 90% and 60% of modified identical sliding knots, respectively, became untied, significantly more than all other knots. When 0-0 and 2-0 Lactomer sutures were used, modified identical sliding knots should be avoided.