Numerous extraarticular suture methods have been described for cranial cruciate ligament (CCL) repair in dogs, including a lateral fabellotibial suture, lateral and medial fabellopatellar sutures, and the more recent tight rope procedure. This paper compared the mechanical properties of load to failure and cyclic elongation for 5 commercial orthopedic suture materials. Ideally, the mechanical properties of suture material include high tensile strength without elongation, stiffness under cyclic fatigue, and good knot security without being bulky. The authors showed that polyblend orthopedic materials performed significantly better than a monofilament nylon leader. All polyblend sutures exceeded the lowest calculated minimum physiologic loads about the canine stifle, but none did well enough to suggest that it would tolerate the mechanical loads a medium-sized dog may generate during daily activity. The authors also found that many sutures had reasonably high ultimate tensile strength, but this may be after excessive elongation if a single strand of suture was used.
In this study, the tension of 5 suture materials was compared by mechanical testing until ultimate failure occurred, specifically evaluating the force required for failure, length difference at failure, and force at 3- and 5-mm elongation. The sutures were also tested to assess suture performance over 1000 cycles of stretching. One polyblend suture, LigaFiba (jorvet.com), needed almost twice as much force before failure than did the other braided sutures and 3 times as much as the nylon suture. It also withstood the most force to achieve 3- and 5-mm elongation. Data provided at the clinically important 3-mm elongation may be more important to clinicians than the ultimate failure points.—Jonathan Miller, DVM, MS, DACVS
Mechanical testing of orthopedic suture material used for extraarticular stabilization of canine cruciate ligament-deficient stifles. Rose ND, Goerke D, Evans RB, Conzemius MG. VET SURG 41:266-272, 2012.