Abstract

Periprosthetic joint infection (PJI) represents a prevalent and severe complication following orthopedic surgery, frequently resulting in impaired bone healing and prosthesis loosening. Conventional treatment approaches, including antibiotics and surgical revision, demonstrate limited efficacy. Consequently, there is an urgent demand for novel implant materials that possess both antibacterial and osteogenic properties. This study presents a novel 3D-printed bionic trabecular porous titanium alloy scaffold. The scaffold was enhanced by loading emodin liposomes (EP) into GelMA-tannic acid composite hydrogel (GA), resulting in the Ti-GA@EP composite scaffold. In vitro experiments indicated that the Ti-GA@EP scaffold exhibited substantial antibacterial activity, achieving antibacterial rates of 92% against Staphylococcus aureus (S. aureus) and 88% against Escherichia coli (E. coil) , while effectively inhibiting bacterial biofilm formation. Immunomodulation experiments demonstrated that the Ti-GA@EP scaffold facilitates the transition of macrophages from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. This transition is accompanied by a reduction in the expression of iNOS and TNF-α, while simultaneously upregulating the levels of IL-10 and Arg-1. In vivo experiments confirmed the bone integration efficacy of the scaffold. The bone volume fraction in the Ti-GA@EP group was 10.25% greater than that in the titanium alloy scaffold group. In the periprosthetic infection model, the Ti-GA@EP scaffold demonstrated superior antibacterial properties and enhanced new bone formation. By integrating antibacterial, immunomodulatory, and osteogenic functions, this composite scaffold addresses the limitations associated with the single-functionality of traditional scaffolds. It provides a novel strategy for PJI treatment, with great clinical potential, and is