Tensile strengths of extracorporeal slip knots tied with poliglecaprone and polydioxanone

To compare the tensile strengths of commonly used extracorporeal slipknots when tied with poliglecaprone and polydioxanone.

The tensile strength of seven extracorporeal slip knots and the flat square knot were tested using a tensiometer. Knots were tied in random order with 2/0 poliglecaprone and polydioxanone. The study was designed to demonstrate a 5-newton difference in knot strength with 95% confidence at 80% power. Five knots were studied in each arm of the experiment.

A laboratory experiment.

Force required to break or cause slippage of knots.

Knots tied with polydioxanone had a marginal yet significantly stronger tensile strength of 2.3 N (95% CI 0.1–0.75 N, P = 0.0332). The Tayside, Blood, Hutchon and Western knots had lower tensile strengths than the flat square knot in both poliglecaprone and polydioxanone. The modified Roeder knot was also stronger than the other ligatures when tied in poliglecaprone and more secure than the Western and Tayside knots when tied in polydioxanone.

Slip knots tied in poliglecaprone are marginally less strong than those tied in polydioxanone. No extracorporeally tied slip knot is stronger than the modified Roeder knot.