Biomechanical evaluation of a non-locking pre-manufactured loop suture technique compared to a three-loop pulley suture in a canine calcaneus tendon avulsion model

Objective: The purpose of this cadaveric study was to compare the strength of a non-locking pre-manufactured loop (Speed Whip (TM) [SW]) suture pattern using Fiberwire (R) with the three-loop pulley (TLP) suture pattern using polypropylene for the surgical repair of canine calcaneal tendon avulsion injuries. Methods: In vitro biomechanical study using 22 paired tendons collected from 11 canine cadavers. Paired tendons were repaired with either a SW suture pattern using Fiberloop (R) suture or a TLP suture pattern using polypropylene suture. Tensile loads required to create a 1 mm gap, 3 mm gap, and construct failure were measured. Results: The mean loads to achieve a 1 mm gap in the TLP and SW constructs were not significantly different. Gap formation at 3 mm occurred at significantly lower loads for the SW (106.4 +/- 21.5N) than for the TLP (127.2 +/- 27.5N) (p = 0.05). The mean loads to construct failure for the TLP (172.8 +/- 39.4N) and SW (131.3 +/- 34.3N) were significantly different (p = 0.001). Clinical significance: The TLP with polypropylene suture is superior to the SW using Fiberloop (R) at resistance to 3 mm gap formation.