Biomechanical Comparison of Suture-Relay All-Suture Anchors and Conventional Suture Anchors for Posterior Medial Meniscus Root Repair in Porcine Models.

Background: Posterior medial meniscus root (PMMR) tears (PMMRTs) can be repaired using various techniques to promote healing. However, the biomechanical properties of suture-relay all-suture anchor (ASA) versus conventional suture anchor (CSA) and loop-locking transtibial pullout (TTP) have not been well established. Purpose: To compare the biomechanical properties of PMMR repairs using suture-relay ASA, CSA, and loop-locking TTP. Study Design: Controlled laboratory study. Methods: A total of 33 fresh-frozen porcine knee joints with intact medial menisci were randomly divided into 3 groups, with 11 specimens in each group: ASA, CSA, and TTP. The study involved cyclic loading, with displacement measurements taken after 100, 500, and 1000 cycles. Subsequently, the specimens were loaded until clinical failure (defined as 3-mm displacement) and then to ultimate failure of the construct, with data recorded for displacement after cyclic loading, load to 3-mm displacement, and ultimate load to failure. Results: After 1000 cyclic loadings, the suture-relay ASA group showed considerably less displacement than the loop-locking TTP group (1.8 ± 0.7 mm vs 2.9 ± 0.3 mm; Conclusion: The biomechanical properties after PMMR repair did not statistically differ between the suture-relay ASA and CSA groups. The suture-relay ASA technique had a higher load to failure than the loop-locking TTP technique. Clinical Relevance: The suture-relay ASA technique is a promising option for the repair of PMMRTs; its repairing strength is also comparable to that of the CSA technique. Notably, the suture-relay ASA technique can be utilized without establishing a posteromedial portal, resulting in decreased procedure time and mitigating challenges associated with working from the posterior aspect of the knee.