Laparoscopic knot substitutes. An assessment of techniques of securing sutures through the laparoscope

Advanced interventional laparoscopy has required the development of new methods of securing sutures as alternatives to the three-throw reef knot. A tensiometer was designed to measure the forces required for distraction of various knots or securing devices with different sutures. A three-throw reef knot was used as a control. Each device was tested 15 times, and the tension at which the "knot" slipped was recorded. Titanium clips (Ligaclip, Ethicon), locking polydioxanone clips (Absolok and Lapra-ty, Ethicon), malleable collars, Roeder knots and biocompatible glue (Histoacryl, B Braun Melsungen AG) were all assessed. Sutures secured with Ligaclips, Absolok clips and glue were significantly weaker than the three-throw reef knot. Sutures secured with malleable collars and Lapra-ty clips were as strong as the three-throw reef knot and have potential for use as knot substitutes.