Recent advances in the application of electrospun nanofibrous scaffolds in bone regeneration

This review synthesizes recent advances in electrospun nanofibrous scaffolds for bone tissue engineering (BTE), with emphasis on critical-size bone defects (CSDs) and the limitations of autologous bone grafting. We critically evaluate hybrid strategies that combine electrospinning for nanofiber fabrication with three-dimensional (3D) bioprinting for macropore definition to achieve multiscale architectural complexity. Current evidence indicates a shift toward instructive and bioactive platforms in which hierarchical porosity supports volumetric cell infiltration and vascularization, whereas mechanical competence is improved through inorganic reinforcement and geometric control using melt electrowriting (MEW). Bioactivity is further enhanced by controlled degradation and sustained ionic release, which regulate cell-matrix signaling, osteogenesis, angiogenesis, and the immune microenvironment. Although these hybrid systems more closely reproduce the native extracellular matrix (ECM), major translational barriers remain, including limited manufacturing scalability, batch-to-batch reproducibility, and the need for long-term in vivo validation in clinically relevant models.