Engineering a biomimetic multiphasic suture anchor system for enhanced rotator cuff enthesis regeneration

Abstract

Abstract Conventional suture anchor methods in rotator cuff repair often fail to replicate the native tendon-to-bone interface, leading to re-tears due to stress concentrations and poor biological integration at anchor sites. To address these challenges, we engineered a biomimetic multiphasic scaffold system (BMS) that integrates with standard suture anchors and deliver spatially organized structural and biological cues to enhance enthesis regeneration. The BMS comprises three distinct phases: aligned nanofibrous decellularized bovine Achilles tendon extracellular matrix (dECM) with ‘stiff’ methacrylated hyaluronic acid (MeHA) for tendon regeneration; nonaligned nanofibrous dECM with ‘soft’ MeHA for fibrocartilage formation; and a porous, citrate-based composite scaffold with bioactive glass for bone integration. In vitro , the BMS facilitated zone-specific tenogenic, fibrochondrogenic, and chondrogenic differentiation. Further, in vivo , it promoted successful integrative healing, forming distinct tendon, fibrocartilage, and bone regions at the repair site. This advanced multiphasic scaffold replicates native tissue properties, offering a promising strategy to improve rotator cuff repair. Its integration with conventional suture anchors provides an innovative design that enhances mechanical fixation and guides enthesis healing to reduce re-tear rates. Broadly, this platform offers a versatile solution for biointegrative repair strategies across complex soft-to-hard tissue interfaces.