Is it necessary to tie the medial row in rotator cuff repair double-row constructs when using suture tape?

Abstract

To evaluate the selected biomechanical differences of a double-row trans-osseous equivalent rotator cuff repair with a knotless versus knot-tying medial row using suture tape in regard to repair displacement, stiffness, and ultimate load to failure. Methods: In 16 fresh-frozen human shoulders (8 matched pairs), double-row rotator cuff repairs were performed with medial-row mattress knots (MK) on one side, the other without (NK). Two DVRT (Differential Variable Reluctance Transducer) sensors were attached between the humerus and 3 mm above the repair site and were used to measure the displacement across the repair during cycling. The biomechanical parameters measured were repair displacement, stiffness, and ultimate load to failure. The supraspinatus was loaded in a similar fashion to previously described protocol using cyclic loading and load to failure testing. 1 Results: All data from paired specimens were compared using paired Student t tests. No statistically significant difference (SSD) in displacement across the repair over the 200 cycles of the test was noted between the two groups (MK ¼ 0.591 ± 0.501 mm; NK ¼ 0.439 ± 0.417 mm, p ¼ 0.618). No SSD in stiffness was noted between the two groups (MK ¼ 32.87 ± 6.31 N/mm; NK ¼ 27.98 ± 9.69 N/mm, p ¼ 0.120). No SSD in ultimate load to failure was noted between the two groups (MK ¼ 501.2 ± 126.1 N; NK ¼ 416.8 ± 120.0 N, p ¼ 0.116). Conclusion:There was no statistically significant different between knotless versus knotted medial row double row rotator cuff repair constructs using suture tape in regard to displacement across the repair site, stiffness and ultimate load to failure. Despite previous evidence suggesting inferiority of knotless medial row technique using suture constructs, this evidence may support the biomechanical equivalency of knotless medial row technique using suture tape.

What is the Optimal Construct to Reduce Failure in Arthroscopic Four Anchor Rotator Cuff Repair?

“…26,29,30 A recent biomechanical study by Mijares et al showed no significant difference between a knotted or knotless TOE using suture tape in medial row fixation point displacement, construct stiffness or load to failure in human cadaveric shoulders. 31 In our study there was a significant decrease in symptomatic re-tear rate in patients that had a suture tape RCR with a knotted medial row, with this group being 82% less likely to experience a re-tear.…”

Knotted Versus Knotless Medial-Row Transosseous-Equivalent Double-Row Rotator Cuff Repairs Have Similar Clinical and Functional Outcomes

“… 16 , 18 , 22 , 23 , 24 , 25 , 26 Conversely, Mijares et al. 27 showed that no significant differences exist regarding displacement across the repair site, stiffness, and ultimate load to failure. Other studies have shown that even if present, biomechanical advantages may come at the expense of heightened strain at the medial suture level where the knots are tied.…”

Blended Suture-bridge Technique for Arthroscopic Rotator Cuff Repair

“…Multiple laboratory studies showed no significant difference in contact pressures between untied and tied medial row. 14 , 15 However, we have observed increased gap formation on the articular side in knotless medial-row constructs, which is an unfavorable condition in tendon repairs. Gapping at the repair site also allows synovial fluid leakage to the footprint, which was previously proposed to be an unfavorable environment for tendon healing.…”