Biomechanical characteristics of suture configurations of channel assisted minimally invasive repair versus routine methods in Achilles tendon rupture

Objective To study the biomechanical characteristics of suture configurations using channel assisted minimally invasive repair (CAMIR) versus two regular methods in Achilles tendon rupture. Methods A total of 18 porcine Achilles tendon samples were randomly divided into 3 groups (6 per group), and underwent CAMIR, Ma-Griffith (as control) and Achillon (as control) respectively. Each sample was preloaded with 50 N for 2 min, and then were cycled 1 000 times at 1 Hz between magnitudes of 20 to 100 N, 20 to 191 N, and 20 to 369 until failure. Failure was defined as suture breakage, or suture pullout. Results There was no significant difference in elongation between all groups after 10 cycles. After the first 1 000 cycles, CAMIR group had a elongations of 7.32±1.67 mm and Ma-Griffith group had a elongation of 7.62±1.81 mm with no significant difference (P=0.078), but both of them were longer than that of Achillon group (3.19±0.61 mm) (P=0.000, respectively). Meanwhile, the number of cycles to failure in CAMIR group was 1 000(1 000, 1 000), equivalent to 1 000 (1 000, 1 000) in Ma-Griffith group, while significantly lower than 2 000 (2 000, 2 007) in Achillon group (P< 0.05). Conclusion The strength of CAMIR suture is reliable. In addition, with lower number of suture strands and knots, the CAMIR suture can reduce the risk of suture reactivity. The CAMIR system is worth to be recommended for Achilles tendon rupture.