A new technique for small and secure knots using slippery polyethylene sutures

Abstract

Background Suture knots used in tendon surgery must be strong but small enough so that they do not hinder gliding. For this purpose, we devised a unique “antislip” knot. Methods Three suture materials were used: Ethibond, Fiberwire, and Nespron. They were tied with either the antislip knot using a pair of United States Pharmacopeia (USP) 2 sutures or with a conventional reef knot using USP2 single sutures. The volume and tensile strength of the knots were measured ( n = 25 for each combination of suture and method). Findings The maximum tensile strength was observed with Fiberwire antislip knots with five throws (mean 587 N) and six throws (mean 590 N), and Nespron antislip knots with five throws (mean 554 N) and six throws (mean 552 N); no significant differences were found among the four knots. Tensile strength per volume showed maximum values with Fiberwire antislip knots with four throws (mean 17.4 N/μl) and five throws (mean 16.8 N/μl), and Nespron antislip knots with four throws (mean 17.6 N/μl) and five throws (mean 16.8 N/μl), which were not significantly different and were over 1.25-fold greater than the value for a reef knot. Ethibond had less tensile strength than Fiberwire and Nespron. Interpretation The antislip knot is smaller for the same or greater strength than a conventional reef knot. The 4- or 5-throw antislip knot was most effective for slippery polyethylene sutures such as Fiberwire and Nespron. The antislip knot should improve biological healing of repaired tendons through accelerated rehabilitation.