A New Twist on the Surgeon's Knot: Quantifying Suture Security

The reliability and security of surgical knots play a critical role in wound closure and healing. A surgeon's knot, created by a modification of the square knot in which an extra 'twist' is added to the initial throw, is often used to increase friction and provide stability of the tissue as the knot is completed.

The purpose of this study was to quantify the security of sutures, as influenced by varying numbers of initial twists in a surgeon's knot.

Using pig's feet for simulation, the study compared the security of knots tied with 2 types of sutures in 3 different sizes, examining the impact of 1 to 6 initial twists. Univariable linear regression was performed to evaluate the association between increased twists and the force required to loosen each knot.

These data showed that suture security generally improves with an increasing number of twists, up to 5, beyond which benefits diminish in certain suture sizes.

Increasing the number of twists in a surgeon's knot significantly enhances suture integrity, with optimal results in knot security observed between 3 to 5 twists, suggesting that a balance is necessary between knot security and ease of application.