Biomechanics of surgical knot security: a systematic review

This review aims to identify publications on quantitative biomechanical testing of surgical knot security and the physical factors that determine knot security and failure.

An electronic literature search was performed in accordance with PRISMA guidelines in January 2022 utilizing the PubMed and Google Scholar databases to look for objective biomechanical studies on knot security in surgery using the primary terms 'knot security' and 'biomechanical testing'.

Thirty-six articles were included. Twenty-four configurations of surface, laparoscopic, and arthroscopic knots were studied. Biomechanical tensile testing was used to evaluate knot security in vitro . Load to failure (N) and elongation at knot failure (mm) were quantified by static and cyclic testing to evaluate the knot holding capacity and failure mechanism of slippage or rupture.

This review reassures that the knot configuration, suture materials, suture sizes, and number of throws are key factors in determining the knot's security. Knot configuration has to be simple for laparoscopic and arthroscopic knots due to the confined space of the operating site. With the advent of stronger suture materials for high-tension surgical reconstructive procedures, there is an unmet need to understand the physical behavior of the knot and the factors that determine its resistance to slippage or rupture.Level of Evidence: Level IV.