Does transosseous-equivalent rotator cuff repair biomechanically provide a “self-reinforcement” effect compared with single-row repair?

Background Transosseous-equivalent (TOE) rotator cuff repair has been theorized to be “self-reinforcing” against potentially destructive and increasing tendon loads. The goal of this study was to biomechanically verify and characterize the effect of increasing tendon load on frictional resistance over a repaired footprint for single-row (SR) and TOE repair techniques. Methods In 10 fresh frozen human shoulders, TOE and SR supraspinatus tendon repairs were performed in each specimen. For all repairs, a pressure sensor was secured at the tendon-footprint interface. The supraspinatus tendon was loaded with 0, 20, 40, 60, and 80 N at 0° and 30° abduction. Paired t tests and multivariate regression analyses were used for comparisons. Results The SR repair had significant increases in footprint contact force, area, and pressure between each and all tendon-loading conditions ( P