A comparison of knot security and loop security in arthroscopic knots tied with newer high-strength suture materials.

PURPOSE The purpose of this study was to compare the knot security and loop security of 2 sliding and 1 static arthroscopic knot tied with different types of suture material. METHODS We evaluated 3 commonly used arthroscopic knots (surgeon's knot, Roeder knot, and Weston knot) tied with 6 different braided No. 2 sutures (FiberWire [Arthrex, Naples, FL]; Ethibond [Ethicon, Somerville, NJ]; Orthocord [DePuy Mitek, Raynham, MA]; Herculine [now called HiFi; ConMed Linvatec, Largo, FL]; MaxBraid [Arthrotek, Warsaw, IN]; and UltraBraid [Smith & Nephew, Andover, MA]). Each suture loop was then mounted on a materials testing system, and its circumference was measured at a 5-N preload to assess each knot's ability to maintain a tight suture loop without slippage (loop security). Knot security was measured as the maximum force to failure at 3 mm of crosshead displacement or suture breakage during single-pull load testing. RESULTS We found that tying knots with different types of suture material can affect both the knot security and loop security of various types of arthroscopic knots. When a Roeder knot or surgeon's knot was tied, No. 2 FiberWire had the highest force to failure when compared with similar knots tied with other suture material (P < .001). The loop security for many of the knot and suture configurations was not significantly different. However, No. 2 FiberWire consistently showed the smallest loop circumference when compared with other suture materials. CONCLUSIONS Arthroscopic knots tied with No. 2 FiberWire provide superior knot security and similar loop security compared with other commonly used high-strength polyethylene suture materials. CLINICAL RELEVANCE High-strength sutures exhibit unique mechanical characteristics that may vary significantly between suture types. In addition, knot configuration plays an important role in altering these characteristics as they relate to knot security.