Effect of fluid media on the mechanical properties of continuous pattern‐ending surgeon's, square, and Aberdeen knots in vitro*

Objective To investigate the knot holding capacity (KHC) of pattern-ending square, surgeon's and Aberdeen knots each tied in 4 throw combinations using large gauge suture after exposure to media commonly found in equine abdominal surgery. Study design In vitro mechanical study. Sample population: Knotted suture strands (n = 10/group). Methods Strands of 2 polydioxanone or 3 polyglactin 910 were exposed to 1 of 4 media for 15 minutes. Control suture strands remained dry. Media used included balanced electrolyte solution, 1% sodium carboxymethylcellulose, equine serum, or equine fat. Pattern-ending knots for the 3 knot configurations were loaded to failure in a linear fashion on a materials testing machine to determine KHC. Results Surgeon's knots tied using media-exposed 3 polyglactin 910 had a significantly higher KHC than the same dry knots with 5 and 6 throws. Square knots tied using media-exposed to 3 polyglactin 910 had a significantly higher KHC than the same dry knots at 5 throws. Aberdeen knots tied with either media-exposed 2 polydioxanone or 3 polyglactin 910 had a significantly higher KHC than their equivalent dry knots. Aberdeen knots had a superior KHC, while requiring less suture than both surgeon's and square knots. Conclusion Media exposure either had no effect on KHC or significantly improved the KHC of all knots investigated. Based on KHC and knot volume, Aberdeen knots tied using media-exposed 3 polyglactin 910 with 3 throws and 1 turn are recommended to end a continuous suture pattern.