Unlocking the potential of injectable hydrogels for cartilage repair.

Osteoarthritis (OA), a prevalent degenerative joint disease, poses significant global health implications and is characterized by progressive degradation of articular cartilage, resulting in debilitating pain and disability. Current treatments often provide only symptomatic relief or require multiple invasive open-joint procedures that are both costly and surgically complex. This review intends to evaluate key design considerations, drawing inspiration from clinically approved therapeutics and recent advances in the field that can truly unlock the potential of injectable hydrogels in cartilage tissue engineering. These include the choice of cargo, hydrogel architecture, and critical factors that are often overlooked in injectable hydrogels, such as ensuring integration with native tissue and restoring joint lubrication. The manuscript also addresses key barriers to clinical translation, including navigating stringent regulatory pathways and optimizing hydrogel performance to meet the mechanical and biological demands of the joint environment. Finally, the review outlines future research directions with emphasis on acellular off-the-shelf strategies, and personalized medicine approaches informed by advances in -omics and high-throughput screening data to accelerate the clinical translation of next-generation injectable hydrogels for effective cartilage repair.