Unlike their peripheral nervous system counterparts, the capacity of central nervous system neurons and axons for regeneration after injury is minimal. Although a myriad of therapies (and different combinations thereof) to help promote repair and recovery after spinal cord injury (SCI) have been trialed, few have progressed from bench-top to bedside. One of the few such therapies that has been successfully translated from basic science to clinical applications is electrical stimulation (ES). Although the use and study of ES in peripheral nerve growth dates back nearly a century, only recently has it started to be used in a clinical setting. Since those initial experiments and seminal publications, the application of ES to restore function and promote healing have greatly expanded. In this review, we discuss the progression and use of ES over time as it pertains to promoting axonal outgrowth and functional recovery post-SCI. In doing so, we consider four major uses for the study of ES based on the proposed or documented underlying mechanism: (1) using ES to introduce an electric field at the site of injury to promote axonal outgrowth and plasticity; (2) using spinal cord ES to activate or to increase the excitability of neuronal networks below the injury; (3) using motor cortex ES to promote corticospinal tract axonal outgrowth and plasticity; and (4) leveraging the timing of paired stimuli to produce plasticity. Finally, the use of ES in its current state in the context of human SCI studies is discussed, in addition to ongoing research and current knowledge gaps, to highlight the direction of future studies for this therapeutic modality.

中文翻译：

---

电刺激作为促进受伤脊髓可塑性的工具。

与周围神经系统对应物不同，中枢神经系统神经元和轴突在受伤后再生的能力很小。尽管已经尝试了无数疗法（及其不同的组合）来帮助促进脊髓损伤 (SCI) 后的修复和恢复，但很少有人从台式到床边。已成功从基础科学转化为临床应用的少数此类疗法之一是电刺激 (ES)。尽管 ES 在周围神经生长中的使用和研究可以追溯到近一个世纪，但直到最近才开始在临床环境中使用。自从那些最初的实验和开创性的出版物以来，ES 在恢复功能和促进愈合方面的应用已经大大扩展。在这次审查中，我们讨论 ES 随着时间的推移的进展和使用，因为它与促进轴突生长和 SCI 后功能恢复有关。在这样做时，我们考虑了基于提议或记录的潜在机制的 ES 研究的四个主要用途：（1）使用 ES 在损伤部位引入电场以促进轴突生长和可塑性；(2)利用脊髓ES激活或增加损伤下方神经元网络的兴奋性；(3)利用运动皮层ES促进皮质脊髓束轴突的生长和可塑性；(4) 利用成对刺激的时机产生可塑性。最后，除了正在进行的研究和当前的知识差距外，还讨论了在人类 SCI 研究背景下当前状态下 ES 的使用，以强调这种治疗方式的未来研究方向。