A biomechanical comparison of a tendon repair device and 4 stranded, cruciate repair sutures for flexor tendon ruptured.

OBJECTIVE

To compare the biomechanical properties of the single strand monofilament Nylon 2-0 Khon Kaen tendon repair device for flexor tendon repair and standard 4-stranded cruciate repair sutures.

MATERIAL AND METHOD

80 flexor digitorum longus tendons from fresh cadavers, were cut and sutured by Khon Kaen tendon repair device (core nylon) or 4-stranded, cruciate repair (3-0 monofilament nylon) and both groups were divided into two groups; the first group combined with 5-0 monofilament nylon circumferential epitendinous suture and the second group without epitendinous suture. The sutured tendons were tested by using biomechanical testing machine (LLOYD instruments, LR30K), in rate 5 mm/s. Force, stiffness and energy absorbed at peak force (calculated from the force-displacement curves) and mode of failure were compared

RESULTS

The Khon Kaen tendon repair device (core nylon) without epitendinous sutured group has 2 mm gap force, peak force and stiffness significantly lower than standard 4-stranded, cruciate repair; but with no statistical difference in the epitendinous sutured group; 90% of Khon Kaen tendon repair device failed by suture breakage and 10% failed by ankle pullout.

CONCLUSION

Although the strength of Khon Kaen tendon repair device (core nylon) alone is lower than the strength of 4-stranded, cruciate repair, and 90% mode of failure was core suture breakage, the authors recommended to change core suture from nylon to a stiffer material and re-inforced with epitendinous suture.