3D-Printed Porous Titanium Alloy Scaffolds Incorporated With Tetramethylpyrazine-Loaded Composite Hydrogels Enhance Angiogenesis and Bone Repair for Femoral Head Osteonecrosis.

Osteonecrosis of the femoral head (ONFH) is a debilitating condition caused by compromised local blood supply to the femoral head, which leads to bone tissue death. The primary therapeutic goals are to restore blood perfusion and reconstruct the damaged bone structure. In this study, we present an advanced three dimensional printed multifunctional composite scaffold that integrates structural biomimicry, sustained drug release, and microenvironment regulation to enable the sequentially coordinated augmentation of ONFH repair. The scaffold features Voronoi-designed porous titanium alloy biomimetic trabeculae that provide robust mechanical support, combined with a gelatin methacryloyl and silk fibroin hydrogel-liposome dual-release system. This design ensures mechanical stability, bioactive functionality, and sustained delivery of tetramethylpyrazine. In vitro assessments demonstrate its excellent biocompatibility, promoting osteogenic differentiation and angiogenic tube formation. In vivo studies using a rat ONFH model reveal significantly increased new bone volume and density, accompanied by enhanced angiogenesis and bone repair. Thus, this scaffold presents a promising strategy for the early treatment of hip-preserving ONFH.