Dual-functional composite hydrogel platform: A "kill two birds with one stone" strategy for anti-infection and osseointegration in the treatment of infectious bone defects

Infectious bone defect (IBD), caused by various factors, frequently recur and are challenging to cure. Current treatments predominantly rely on a combination of antibiotics and traditional surgery, yet they have not significantly reduced long-term recurrence rates. Given the complex microenvironment and persistent mechanisms mediated by bacteria, it is crucial for implants to enhance osseointegration while ensuring sustained and effective infection control. Hydrogels have emerged as a promising solution in bone tissue engineering due to their excellent drug-loading efficiency, controlled drug release, adjustable mechanical strength, and biocompatibility. Over the past decade, hydrogels with dual anti-infection and pro-osseointegration functions have demonstrated excellent efficacy in treating IBD, making their clinical application possible. This review summarizes current clinical treatments for IBD, highlighting the pros and cons of traditional implants and the infection-mediated complex immune and bone microenvironments. Additionally, it discusses the essential physicochemical properties of hydrogels suitable for the IBD microenvironment and reviews the latest advancements in various dual-functional hydrogels. Finally, it addresses future application prospects, technical challenges, and unresolved issues in the development of dual-functional hydrogels. Overall, this review aims to facilitate the advancement and clinical implementation of dual-functional hydrogels tailored to the complex therapeutic needs of IBD.