Creating a small anchor to eliminate large knots in mesh and tape suture

Wide mesh or tape sutures are used to close high-tension wounds such as in hernia or tendon repair. However, wide sutures produce large knots that are susceptible to increased palpability, infection, and foreign body response. To prevent such adverse events, we developed a small suture anchor to replace wide suture knots. The suture anchor was iteratively developed using threedimensional (3D) design software and produced via 3D printing. Anchor prototypes underwent monotonic, cyclic fatigue, and stress-life testing in a benchtop soft tissue suture model. Results were compared to a standard of care knot and alternative suture fixation devices. The final anchor design was selected based on minimal size and mechanical performance. The size of the final anchor (200mm3) was 33% smaller than a tape suture knot and 68% smaller than a mesh suture knot. Monotonic testing of mesh and tape sutures revealed a significantly greater anchor failure load compared to knot and alternative fixations (p < 0.05). Additionally, all anchors successfully completed cyclic fatigue testing without failure while other fixations, including knot, failed to complete cyclic fatigue testing multiple times. Stress-life testing demonstrated durable anchor fixation under varying tensile stresses. Failure mode analysis revealed anchor fracture and tissue failure as modes of anchor failure, each of which occurred at supraphysiologic forces. We created a small suture anchor that significantly outperforms knot and alternative suture fixations in benchtop testing and addresses concerns of increased palpability, infection, and foreign body response from large suture knots.

Duke Scholars

Author Beiyu Liu  

Author Ken Gall Thomas Lord Department of Mechanical Engineering and Materia ...