Summary

A novel all-suture anchor technique can be an alternative technique for posterior medial meniscal root repair with high reproducibility and superior biomechanical properties for meniscal root repair.

Abstract

Background

Posterior medial meniscal root (PMMR) repair can restore meniscal function and knee kinematic, resulting in significantly lower rates of OA progression and TKA conversion rate. A novel technique all-suture anchor for meniscus root repair which can be done with standard anteromedial and anterolateral portal has been developed. However, the biomechanics comparison between a novel all-suture anchor repair (AS) to conventional technique including the transtibial pullout (TP) and suture anchor repair (SA) technique for PMMR repair has not been established.

Purpose

To compare the biomechanical properties in terms of cyclic displacement, load to 3 mm displacement and ultimate load to failure between three different techniques for PMMR repair in porcine knee.

Study Design: Controlled laboratory study

Methods

A total of thirty-three fresh-frozen porcine knee joints with intact medial meniscus were randomly allocated into three meniscal root repair techniques (n=11 per group, transtibial pullout, suture anchor and all-suture anchor). All specimens were subjected to cyclic loading followed by load to 3 mm displacement and ultimate load to failure, respectively. All loads were applied parallel with the circumferential meniscal fibers near the posterior medial meniscal root repair construction.

Result: After 1000 cycles, the least displacement was AS (mean ± SD, 1.75 ± 0.2 mm), followed by the SA (2.21 ± 0.79 mm), and TP (2.89 ± 0.31mm) groups. After 100, 500, and 1000 cycles, suture displacements using the SA and TP techniques were not significantly different, while the AS technique resulted in significantly less displacement than the TP (P< .05) techniques at 100 and 1000 cycles. The load to 3 mm displacement of AS (61.29 ± 6.49) and SA (57.54 ± 9.65N) were significantly higher than TP (38.34 ± 9.44 N) technique (P < .05). The ultimate load to failure of the AS (152.98 ± 55.05 N) technique can provide significantly higher than TP (101.96 ± 12.94 N) technique. During ultimate load to failure testing, the mode of failure in the AS and SA were heterogeneous while all TP constructs failed by suture elongation at meniscus suture interface. Displacement at failure was indistinguishable between three techniques.

Conclusion

There were no significant different biomechanical properties between all-suture anchor and suture anchor technique while all-suture anchor can provide superior biomechanical properties than transtibial pullout technique for posterior medial meniscal root repair at time zero which is sufficiency to allow partial weight bearing in early postoperative rehabilitation programs.

Keywords: meniscal root; root tear; meniscus repair; all-suture anchor; suture anchor; transtibial pullout