Biomechanical testing of a novel tendon implant device for the repair of equine flexor tendon lacerations.

The research investigates the strength and failure features of a novel tendon implant compared to the 3 loop pulley suture pattern for repairing lacerations in the superficial digital flexor tendon (SDFT) of horses. The results show that the 3 loop pulley suture endured significantly greater load than the novel implant, however, both resisted similar tension until a 2 mm gap.

Study Design and Methods

• The study was experimental and utilized cadaveric equine forelimbs’ SDFTs.
• 16 of these tendons were divided into two groups of 8; one group employed the traditional 3 loop pulley (3LP) suture pattern technique and the other group used the new stainless steel suture and anchor implants (SA).
• Factors like ultimate load before failure, mode of failure, gap at failure, and load required for a 2mm gap were measured using a materials testing system paired with a high-speed camera.
• Overall comparison of the two techniques was made using Student’s t-test with a significance level set at P ≤ .05.

Results

• The 3LP was found to withstand a significantly greater load (363.5 ± 83.7 N) before failure compared to the SA implant (132.4 ± 26.8 N).
• However, the difference in load before a 2 mm gap occurred was not significant for the two methods (3LP = 164.9 ± 67.7 N, SA = 114.5 ± 21.5 N with P = .09).
• Failure modes for each method were different; the 3LP failed due to suture pull out while the SA implant failed due to anchor pull out.
• Lastly, the gap at failure was significantly larger in the 3LP method than in SA repair technique.

Conclusions

• A key finding of this study is that both the SA repair and the 3LP resisted similar tension until a 2 mm gap.
• However, the ultimate load before failure of the SA repair was only 36% that of the 3LP repair, implying that the 3LP suture method was significantly stronger.