The Fixable Suture Anchor Plate: A Mechanical Comparison to Other Devices Commonly Used for Tendon Anchorage to Bone During Rotator Cuff Repair Surgery

Background: The fixable suture anchor plate is a new device that has been designed with the intention of improving anchorage- to-bone strength during tendon-to-bone repair in patients with compromised bone quality. In this invitr o study we compare the load-to-failure and mode-of-failure results of a fixable suture anchor plate to that of other devices that are commonly used during rotator cuff repair surgery, including: a buttress plate, metal suture anchors, bioabsorbable suture anchors, and suture through simple tunnels without any augmenting device. We hypothesized that the fixable suture anchor plate would provide higher load-to- failure measurements compared to the other devices. Methods: Each device was implanted into solid rigid polyurethane foam blocks with densities representing varying degrees of osteoporosis, and then tested to failure. ANOVA and post-hoc analysis tests were used to determine statistical significance. Results: The average load to failure for the fixable suture anchor plate was significantly greater in low and medium density blocks compared to the other devices tested (p≤0.01). The greatest difference in magnitude was seen in low density blocks (5pcf), where the fixable suture anchor plate failed at 278 ± 53 N (mean ± standard deviation), about double the value of the next highest failure at 133 ± 11 N for the buttress plate. Conclusions: The fixable suture anchor plate demonstrated superior anchorage strength in low and medium density foam blocks compared to the other devices that were tested in this study. Further studies are needed to determine whether clinical use of a fixable suture anchor plate will translate into a higher rotator- cuff-repair success rate invivo.