Abstract
AIMS: This study aimed to biomechanically compare three medial meniscus posterior root tear (MMPRT) repair techniques to support their clinical application. METHODS: A total of 18 porcine knee joints and 12 bovine extensor tendons were allocated into three groups: transtibial pullout repair (TPR), tendon reconstruction (TR), and tendon-suture complex (TSC). Each sample underwent cyclic loading (1 to 30 N, 1,000 cycles), followed by failure testing. Displacement, elongation, stiffness, ultimate load, and failure modes were assessed. RESULTS: Significant mean differences were detected between the TPR and TSC after 100 cycles (2.27 mm (SD 0.26) vs 1.89 mm (SD 0.20), p = 0.012), and also between the TSC and TPR or TR after 500 and 1,000 cycles (500 cycles: 2.08 mm (SD 0.22) vs 2.62 mm (SD 0.27) and 2.50 mm (SD 0.13), p = 0.001 and p = 0.009, respectively; 1,000 cycles: 2.22 mm (SD 0.21) vs 2.86 mm (SD 0.31) and 2.71 mm (SD 0.20), p = 0.001 and p = 0.011, respectively), while no significant difference was detected between the TPR and TR. The ultimate failure load in the TSC was greater than that in the TR (277.43 N (SD 75.57) vs 176.88 N (SD 36.80), p = 0.038) and did not differ from that in the TPR. TR and TSC presented a lower elongation than that noted in the TPR (14.09 mm (SD 4.32) and 13.88 mm (SD 4.59) vs 26.89 mm (SD 7.27), both p = 0.003), with no difference noted between TR and TSC. Stiffness was greater with the TSC than with TPR (23.82 N/mm (SD 6.94) vs 14.34 N/mm (SD 2.39), p = 0.028) and did not differ between TPR and TR or between TR and TSC. Failure modes varied: TPR failure by suture pull-through, and TR and TSC failure by tendon pull-through. CONCLUSION: TR and TSC outperformed TPR, with TSC resulting in better displacement, elongation, and stiffness, and a higher ultimate failure load than TR. These findings suggest that suture augmentation enhances repair strength. TSC shows favourable biomechanics, but further clinical validation and rehabilitation optimization are needed for better long-term outcomes.