Initial fixation strength of flexible all-inside meniscus suture anchors in comparison to conventional suture technique and rigid anchors - Biomechanical evaluation of new meniscus refixation systems

Background: The newest generation of meniscus repair devices is designed to combine the benefits of the all-inside technique with the biomechanical properties of sutures. Hypothesis: New flexible all-inside suture anchors have better fixation strength than rigid anchors, but there is no difference when compared to conventional horizontal and vertical mattress sutures. Study Design: Controlled laboratory study. Methods: In fresh-frozen bovine menisci, initial fixation strength, stiffness, and failure mode of different meniscus fixation techniques (FastT-Fix, RapidLoc, Meniscus Arrow, horizontal and vertical 2.0 Ethibond sutures) were evaluated in a computer-based materials testing machine at a rate of 12.5 mm/sec. Results: The vertical and horizontal FastT-Fix suture anchors were the strongest devices with regard to pullout strength, with no significant difference compared to the vertical 2-0 Ethibond sutures. Horizontal sutures, Meniscus Arrow, and RapidLoc had significantly lower pullout strength. Vertical and horizontal FastT-Fix suture anchors showed significantly higher stiffness than the other devices. Conclusions: Biomechanical properties of flexible all-inside meniscus anchors (FastT-Fix) are comparable to conventional vertical suture techniques. Characteristics of the flexible RapidLoc are comparable to rigid anchors (Meniscus Arrow). Clinical Relevance: From the biomechanical point of view, flexible all-inside meniscus refixation devices are an alternative to conventional suture techniques and rigid meniscus anchors.