Knot tying is often executed with technical errors resulting in slip knots with less than optimal security and high incidence of dangerous knots. The participants' surgical experience did not have any correlation with their knot security (r = -0.044, p = 0.833). Three out of 12 participants who thought they had created square knots actually created square knots and the rest produced slip knots. Some 12.6% of Vicryl knots and 5.6% of Prolene knots were dangerous and all of these were slip knots with up to 6 throws. For Prolene, 3-throw square knots were superior to 6-throw slip knots (p = 0.035). For Vicryl, 4-throw square knots were superior to 6-throw slip knots (p < 0.001). Square knots had significantly higher tensile strength than slip knots (p < 0.001). The incidence of knot slipping under tension was significantly lower with square knots (p < 0.001). Square knots accounted for only 12.8% of all the knots. Of the 25 participants, 2 created square knots consistently, 2 created a mixture of square and slip knots, and 21 created only slip knots. Knots with tensile strength of less than 5 N were considered dangerous. All knots were tested for tensile strength using a tensiometer. With each suture material, the participants tied: in series 1, 4 knots as they would normally do during surgery in series 2, 4 knots with 3 throws, 4 knots with 4 throws, 4 knots with 5 throws, and 4 knots with 6 throws.

Twenty-five participants were requested to tie 40 knots each, using Vicryl 2-0 and Prolene 2-0 sutures.

This study aimed to assess surgical trainees' knot tying technique and determine the type and security of knots created.

Surgery knot tying