Convergence of 3D bioprinting, bone organoids, and organ-on-chip systems for orthopedic disease modeling and regenerative applications
Bone disorders remain difficult to model because native bone is a mineralized, vascularized, mechanosensitive, and multicellular organ whose remodeling depends on tightly coordinated matrix, transport, biochemical, and mechanical cues. This review examines how 3D bioprinting-enabled bone organoids and organ-on-chip systems can be integrated to construct more physiologically relevant platforms for orthopedic research. Unlike previous reviews that discuss bone organoids, 3D bioprinting, or bone-on-chip systems as separate technologies, this review addresses the conceptual and translational gap between biological self-organization, programmable biofabrication, and dynamic microphysiological regulation in orthopedic modeling. We synthesize current advances in bone microenvironment modeling, focusing on organoid-based biomimicry, programmable scaffold fabrication, perfusable and mechanically active chip systems, and disease-oriented applications. The analysis shows that 3D bioprinting transforms bone microenvironment reconstruction from empirical scaffold fabrication into a controllable strategy in which matrix composition, pore architecture, mineralization, vascular-like channels, multicellular organization, and biochemical patterning can be systematically engineered. Organ-on-chip platforms further enhance these constructs by introducing dynamic perfusion, mechanical stimulation, compartmentalized crosstalk, and disease-relevant microenvironmental regulation. Together, these technologies support emerging applications in bone defect repair, osteoporosis and metabolic bone disease modeling, osteoarthritis and osteochondral interface reconstruction, and bone tumor or metastasis research. Despite persistent limitations in tissue maturation, vascular hierarchy, immune and hematopoietic integration, long-term stability, and standardization, the convergence of organoids, 3D bioprinting, and microphysiological systems provides a versatile foundation for mechanistic studies, drug evaluation, personalized therapeutic testing, and future regenerative strategies in orthopedics.
