The effect of six knotting methods on the biomechanical properties of three large diameter absorbable suture materials.
OBJECTIVE
To evaluate the effect of 6 different knotting methods on the mechanical properties of 3 large absorbable suture materials used in large animal surgery.


METHODS
In vitro mechanical study. Sample Population- Knotted suture loops (n=15 per group).


METHODS
Suture loops were created between two low-friction pulleys with either 2 polydioxanone, 2 polyglactin 910 or 3 polyglactin 910. Strands were tied using 1 of 6 knotting technique: square knot, surgeon knot, clamped surgeon's knot, sliding half-hitch knot (HH), Delimar knot and self-locking knot (SLK). A single cycle to failure test was performed on each suture loop with a distraction rate of 100 mm/min. Failure modes were evaluated and breaking strength, elongation to failure and stiffness were compared.


RESULTS
All loops except two HH failed at the knot by acute breaking. The double-stranded SLK was both stronger and stiffer than all other knots for each suture material. Clamping the first throw of the surgeon knot decreased load to failure significantly (143.11 +/- 8.64 N) compared with not clamping (159.21 +/- 6.14 N) for polydioxanone. Stiffness and elongation to failure were respectively lower and increased for 2 polydioxanone compared with both polyglactin 910 materials for all knotting techniques.


CONCLUSIONS
Knotting techniques do influence structural properties of suture loops. The double strand loop conferred stiffer and stronger properties to the SLK CLINICAL RELEVANCE: Clamping the first throw of polydioxanone should be avoided when tying a suture under tension even using large diameter suture materials. Using a SLK might be considered as a useful alternative when excessive tension is present.
Clinical Sciences, Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Université de Montréal, and the Biomedical Engineering Département, Ecole Polytechnique de Montréal, QC, Canada. pymulon@cvm.tamu.edu
Pierre-Yves
PY
Mulon
Fouad
F
Zhim
L'Hocine
L
Yahia
André
A
Desrochers
D000818:Animals; D066298:In Vitro Techniques; D016687:Polydioxanone; D011098:Polyglactin 910; D013525:Surgical Instruments / Q000662:veterinary; D013536:Suture Techniques / Q000662:veterinary*; D013537:Sutures / Q000662:veterinary*; D013718:Tensile Strength
D016687:Polydioxanone; D011098:Polyglactin 910