Sponsor: National Institutes of Health (in Collaboration with Florida Institute of Technology)
Anterior cruciate ligament (ACL) plays a crucial role in stabilizing the knee joint. ACL ruptures are highly common and very serious musculoskeletal injuries, with numbers steadily increasing, particularly among female athletes. Effective treatment to re-stabilize the joint often involves surgical reconstruction using for example, a tendon graft to replace the ACL. While viable graft choices for ACL reconstruction (ACLR) are clinically available, graft failure is reported in approximately 10% of patients. Failure rates for revision ACL surgeries are significantly higher and cause significant morbidity. Poor integration at the bone-fibrocartilage-ligament interface (i.e., enthesis) is attributed to be the key reason for graft failure. Therefore, there is an urgent need for a viable strategy to improve graft integration, permit appropriate interfacial load distribution, and promote more efficient healing of graft within the bone structure post-ACLR. Recreating the complex gradient in enthesis tissue composition and organization at the ligament-bone insertion site is critical for reliable integration of ACL grafts. Previously, Dr. Vipuil Kishore at the Florida Institute of Technology (FIT), has used 3D printing technologies to develop a continuous Bioglass-gradient integrated collagen matrix (BioGIM) that emulates the mineral composition gradient in the native ACL enthesis. In this current study, we propose to: 1) develop an innovative 4D printing methodology to introduce a high degree of collagen alignment that can topographically guide ligamentous differentiation on the pure collagen side of the BioGIM, and 2) assess the efficacy of the BioGIM to improve graft integration with bone in an ACLR model.