Weak direct current (DC) electric fields as a therapy for spinal cord injuries: review and advancement of the oscillating field stimulator (OFS)

  • Jianming LiEmail author


Traumatic injury to the spinal cord remains a catastrophic event that has lifelong consequences. While decades of research have elucidated much of the pathophysiology associated with spinal cord injury (SCI), there still remains no clinically approved treatments for restoring lost sensorimotor function. The traditional dogma suggests central nervous system (CNS) neurons do not regenerate after injury but active areas of research aim to overcome this biological bottleneck. One particular approach using low-level direct current electric fields (DC EFs) appears especially promising based on a rich set of experimental data. This review highlights the biological basis for EF-induced regeneration and discusses the pre-clinical and clinical trials using the oscillating field stimulator (OFS)—a medical device designed to deliver DC EFs in vivo. I further report ongoing developments in our laboratory that refreshes the OFS concept with the hope of renewing interest in conducting additional clinical trials.


Direct current electric fields CNS Spinal cord injury Spinal regeneration Oscillating field stimulator 



I would like to thank Michel Schweinsberg and Megan Saenger for the illustrations and Dr. Richard Borgens for thoughtful discussions.


This work was financially funded by the State of Indiana.

Compliance with ethical standards

Conflict of interest

The author declares no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

No human subjects were involved, and no informed consent was required for this review.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Center for Paralysis Research, Department of Basic Medical Sciences, College of Veterinary MedicinePurdue UniversityWest LafayetteUSA

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