Mechanical performance of surgical knots in a vaginal surgery model

Objective: To evaluate the integrity of 3 different types of sliding knots in a vaginal surgery model. Study Design: Nonidentical sliding (NS), loop-to-strand sliding (LTS), and parallel sliding (PS) knots with 4 throws each were tied on a vaginal surgery model with 0 polyglactin-910 and tested until failure. The main outcomes studied were the maximum load reached at failure and the proportion of each type of sliding knot that either unraveled or broke during standardized laboratory testing. Results: PS knots were significantly stronger than either NS or LTS knots, with no difference in strength between NS and LTS knots. Most of the NS and LTS knots failed by slippage, where as most of the PS knots failed by rupture at the knot site. Conclusions: PS knots using 0-vicryl are significantly stronger than NS and LTS knots and should be preferentially considered when performing vaginal surgery.