Abstract

A bone-nerve scaffold is developed to achieve “structure + physiology” systematic repair. • The scaffold is multimodally 3D print for individualization in clinical scenarios. • Bioelectricity and aligned fibers rise neurogenesis and nerve-driven osteogenesis. • The scaffold restores bone, nerve and bone-nerve interface in a canine model. Bioelectric approaches hold great promise for tissue regeneration. However, dense mineralized tissues such as bone restrict intrabony fluid flow, thereby limiting stable current generation and real-time regulation. Conventional bioelectric strategies are largely preset and cannot dynamically match the complex and rapidly changing physiological environment of injured tissues, which limits their efficacy. Inspired by the extracellular electron transfer strategies of Shewanella oneidensis , this study developed a biomimetic live battery that harnesses body fluids as active reactants to generate sustained, self-powered intrabony currents with real-time damage sensing and autonomous modulation. This adaptive bioelectric strategy transcends preset stimulation paradigms and repurposes physiological fluids as functional components of an injury-responsive energy unit. Using high precision 3D printing, an electrically active, axon-guiding nerve conduit and a cancellous-bone-mimetic scaffold were fabricated and assembled to form the OEF-AMF@CP scaffold for integrated bone-nerve regeneration. OEF-AMF@CP recreates a reciprocal microenvironment in which bone protects nerves and neurotrophic signaling enhances osteogenesis. The manufacturing approach provides geometric versatility, reproducibility, and scalability, enabling the construct to serve as a modular unit adaptable to diverse clinical anatomies and suitable for translational development. In vivo studies showed that the conduit restored rat sciatic nerve to a level comparable with autograft. In a canine model, OEF-AMF@CP increased bone mineral density by 57% compared with controls whi