Biomechanical performance of a collagen meniscus implant with regard to suture material and irrigation fluid.

BACKGROUND: The role of meniscus scaffolds remains controversial as failure rates remain high. The aim of this study was to evaluate the pullout strength of different suture materials used for fixation of the Collagen Meniscus Implant (CMI) regarding different suture materials, and type or temperature of irrigation fluid.

METHODS: One-hundred and twelve specimens were utilized with horizontal sutures and mounted to a dedicated test device. Loads were applied perpendicular to the CMI, until failure. Two differing suture materials - polydioxanone (PDS) and non-absorbable, braided polyester sutures (NABP) - were evaluated. Additionally, two common irrigation fluids - lactated Ringer's and electrolyte-free, hypotonic Mannitol-Sorbitol solution - were evaluated. Specimens were further evaluated according to different temperatures of the irrigation fluid. Half of the constructs were tested at room temperature (20°C) and half were evaluated at near-core body temperature (37°C).

RESULTS: PDS sutures showed a significantly higher load-to-failure compared to NABP sutures (P=0.0008). Regarding the type of irrigation fluid, the electrolyte-free Mannitol-Sorbitol solution showed a significantly higher load-to-failure compared to the overall Ringer group (P b 0.0001). This was equivalent for both the PDS (P=0.015) and for the NABP sutures (P b 0.0001). The temperature of the irrigation fluid did not significantly influence load-to-failure.

CONCLUSIONS: PDS sutures and electrolyte-free Mannitol-Sorbitol irrigation fluid provided the best biomechanical properties regarding load-to-failure testing. This study underlines the potential to improve construct stability for the CMI by alteration of the suture material and the type of irrigation fluid, which should be considered whenever scaffold fixation is conducted.