Bioinspired injectable hydrogels for bone regeneration

• A unique bioinspired design perspective, offering fresh insights for injectable hydrogel development in bone/cartilage regeneration. • A comprehensive overview of injectable hydrogel applications across multiple bone disease models, surpassing existing reviews in both scope and depth. • Systematic categorization and elucidation of various bioinspired strategies for injectable hydrogels, exceeding current methodologies in precision and comprehensiveness. • Exploration of the integration of emerging technologies like artificial intelligence in injectable hydrogel research, paving the way for future advancements. • Injectable hydrogels with attractive potential for enhancing organoid applications; their synergistic integration marking the onset of a groundbreaking era in organoid-centric research and therapeutic strategies. The effective regeneration of bone/cartilage defects remains a significant clinical challenge, causing irreversible damage to millions annually. Conventional therapies such as autologous or artificial bone grafting often yield unsatisfactory outcomes, emphasizing the urgent need for innovative treatment methods. Biomaterial-based strategies, including hydrogels and active scaffolds, have shown potential in promoting bone/cartilage regeneration. Among them, injectable hydrogels have garnered substantial attention in recent years on account of their minimal invasiveness, shape adaptation, and controlled spatiotemporal release. This review systematically discusses the synthesis of injectable hydrogels, bioinspired approaches-covering microenvironment, structural, compositional, and bioactive component-inspired strategies-and their applications in various bone/cartilage disease models, highlighting bone/cartilage regeneration from an innovative perspective of bioinspired design. Taken together, bioinspired injectable hydrogels offer promising and feasible solutions for promoting bone/cartilage regeneration, ultimately laying the foundations for clinical applications. Furthermore, insights into further prospective directions for AI in injectable hydrogels screening and organoid construction are provided.