Electrical Microenvironment Reconstruction and the Application of Biomaterials in Spinal Cord Injury

The key challenge in restoring neural function after spinal cord injury stems from a vicious cycle triggered by the collapse of the bioelectrical microenvironment at the injury site: an ‘electrical silence–neuronal degeneration–glial proliferation’ cascade that conventional therapies fail to reverse. This review systematically summarizes the pathological mechanisms of electrical microenvironment imbalance and its critical role in neural regeneration. Furthermore, current intervention strategies based on biomaterials are outlined: evolving from passive reconstruction of electrical pathways using conductive materials to proactive regulation of local electric fields through exogenous electrical stimulation, which activates key signaling pathways, such as voltage-gated calcium channels, and thereby promotes axonal regeneration, stem cell differentiation, and immune modulation. Although existing strategies face challenges in precision and biocompatibility, this review integrates multidisciplinary perspectives from neuroscience and biomaterials to establish a theoretical framework for designing precise, biocompatible electrically modulating biomaterials. Ultimately, we aim to advance spinal cord injury treatment from local electrical environment restoration toward a paradigm shift toward functional neural circuit reconstruction.