Pre-Clinical Optimization of MeniscoFix, a Novel Total Meniscus Replacement Implant

Meniscal injuries represent one of the most common intra-articular knee injuries, resulting in over 750,000 surgical procedures in the United States annually. Removal of the torn tissue, known as meniscectomy, typically provides short-term relief from pain, discomfort, and instability, but alters the joint’s mechanics, leaving the underlying cartilage susceptible to long-term osteoarthritis. There is currently no FDA-approved implant for total meniscus replacement. Our approach is to replace torn or degenerated menisci with a mechanically functional replacement implant, MeniscoFixTM, capable of being slowly absorbed while remodeling into functional, chondroprotective neo-meniscal tissue. The goal of this Phase I SBIR project is to optimize the design of the MeniscoFix™ implant technology for clinical use in both the medial and lateral meniscus, addressing anatomical, biomechanical, and functional requirements. Aim #1: Optimization of MeniscoFixTM designs for use in both the medial and lateral meniscus. SolidWorks with finite element analysis (FEA) will be used to design and screen fiber reinforcement patterns for medial meniscus and lateral meniscus implants, which differ in anatomy, size, shape, and root attachment sites. Based on FEA simulations, designs which optimally satisfy anatomical and biomechanical design requirements will be selected for subsequent manufacturing and preliminary design verification including tensile, compressive, viscoelastic, and cyclic testing per ASTM F3223-17. Aim #2: Addition of radial fibers to reduce risk of implant extrusion. Prototypes are currently made by stacking multiple 2-dimensional (X-Y) fiber reinforcement patterns using a CNC machine. We will now evaluate various fiber reinforcement patterns in the radial or ‘Z-direction’ to potentially improve biomechanical properties and reduce the risk of implant extrusion after implantation. Aim #3: Mechanical reinforcement of the implant ‘tail region’ required for surgical fixation. The design of the tail region of the implant will be improved to provide for rigid intra-osseous surgical fixation while maintaining implant integrity, reducing risks of loosening or breakage at the tibial attachment sites. Preliminary design validation studies will also be performed to ensure MeniscoFix™ satisfies the needs of the end user. Key Opinion Leaders in Orthopaedic Surgery will evaluate usability characteristics of MeniscoFixTM by performing arthroscopically-assisted meniscus replacement procedures in human cadaver knees. Successful achievement of these SBIR project milestones will further de-risk the technology and improve opportunities to partner with established Orthopaedic medical device manufacturers. The ultimate goal is to provide Orthopaedic surgeons with a novel, safe, and effective treatment option to restore and maintain quality of life in patients suffering from irreparable meniscal injuries or post-meniscectomy syndrome.