Closed-Loop Spinal Stimulation for Restoration of Upper Extremity Function After SCI
Abstract
Objectives Our objectives are to improve control of hand and arm function for people with chronic spinal cord injury to their neck, and also to reduce spasticity that interferes with daily living. We are testing a non-invasive method of stimulating the spinal cord by applying electrodes to the skin over the back of the neck. Rationale We will trigger spinal stimulation based on spared activity of some muscles in order to promote neural circuits that “fire together to wire together.” There is excellent evidence for this “closed-loop” stimulation approach from animal studies, and we will translate this to a pilot human trial for the first time. We also have very encouraging results that even “open-loop” stimulation, simply combined with practice using the hands and arms, leads to profound improvements in hand function. The most exciting part of these past studies is that the benefits outlast the stimulation by 3 to 6 months. Spasticity is also reduced during the stimulation treatment, but this does not appear to last for more than 2 weeks after treatment. Therefore, we will also go back to our animal models to test stimulation patterns that can lead to prolonged improvements in spasticity. Finally, we will test best stimulation patterns in a small group of people with spinal cord injuries at the conclusion of the study. Ultimate Applicability of our Research Our research will directly improve the quality of life for people with long-term injuries to the neck (cervical) region of the spinal cord that results in impaired hand and arm function. We have already observed that open-loop spinal stimulation can return movements to people with complete loss of hand movement and also restore function and quality of life to people with incomplete paralysis. This non-invasive stimulation is very low risk, and is considered non-significant risk by the U.S. Food and Drug Administration. Therefore, it can be rapidly moved from the research phase to the clinical treatment phase and become available for people with spinal cord injury within 2-4 years (depending mostly on delays due to the COVID-19 pandemic). Our research also aims to understand how spinal stimulation can lead to both short- and long-term improvements in spasticity, a significant problem for people with spinal cord injuries that is only partly resolved by treatment with prescription drugs and their associated side effects. Our animal experiments will help us to understand which neural pathways the stimulator is activating as it reduces spasticity in the short-term and how we can change the stimulation parameters to lead to a more prolonged improvement in spasticity even after the stimulation treatment ends. Finally, we have observed compelling improvements in bladder, bowel, cardiovascular, and other “autonomic” function even after open-loop spinal stimulation in our initial studies of people with spinal cord injury. We will continue to track these improvements, which can be as impactful as restoring heart rate regulation to pre-injury levels, resuming sweating, and discontinuing the use of a catheter to manage the bladder. Together, we believe the observed and potential benefits of spinal stimulation far outweigh the minor risks associated with this non-implanted stimulation strategy. Here we seek to revolutionize the patterns of stimulation to lead to even more complete recovery and prolonged improvements in spasticity, bladder, bowel, and autonomic function for people with long-term spinal cord injuries.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Dec 05, 2021
- Source ID
- W81XWH2110551
Entities
People
- Chet T Moritz
Organizations
- United States Army
- University of Washington