Date Presented Accepted for AOTA INSPIRE 2021 but unable to be presented due to online event limitations.
Transcutaneous spinal cord stimulation (TSCS) is a novel mechanism to excite spinal neural circuits and unmask latent voluntary function. This research presentation will discuss outcomes associated with an 8-week trial combining TSCS with therapy. Participants improved in walking function, bowel and bladder function, and sensation with commensurate improvements in quality of life. TSCS is a feasible, meaningful intervention for patients with incomplete spinal cord injury.
Primary Author and Speaker: Rebecca Martin
PURPOSE: There are an estimated 288,000 people living with and 17,700 new injuries per year. The majority of these injuries are motor incomplete and result in some dysfunction in walking. Recovery of walking function is consistently rated as a high rehabilitation priority among patients, dramatically impacting quality of life and independence, and is a common target of therapy. Yet, despite significant research efforts and advances in the field, recovery of independent walking remains an elusive goal for most patients with motor incomplete SCI (iSCI). Transcutaneous Spinal Cord Stimulation (TSCS) is a promising, non-invasive intervention aimed at increasing spinal excitability and unmasking latent function. The purpose of this study was to assess the impact of pairing TSCS with a long-term gait training protocol on the quality of life and walking function of patients with motor incomplete Spinal Cord Injury.
DESIGN: This study was a within-participant, repeated measure design. Participants were recruited from the International Center for Spinal Cord Injury at Kennedy Krieger Institute in Baltimore, MD. Adults, with chronic, motor incomplete, non-progressive SCI, naive to the intervention, were considered for enrollment.
METHOD: The intervention consisted of 24, 2-hour sessions, delivered 3 times per week for 8 weeks. At the start of each session, TSCS was applied between spinous process T11–T12 and over the lower abdomen. A symmetrical biphasic rectangular waveform, at 50 Hz and 1 millisecond, was used to provide 30 continuous minutes of stimulation. During stimulation, subjects participated in strengthening, repeated segmental task practice, and gait-based interventions. Training continued following the stimulation period for the duration of the session to take advantage of the priming and neuromodulation effects provided by the TSCS. To assess feasibility of this intervention we collected attendance compliance, numeric pain rating, and skin response to the stimulation. Clinically useful walk tests were used yo capture any improvements in walking function Tests were completed without TSCS to gain insight into the timing and magnitude of changes in voluntary function. Participants were also interviewed to elucidate changes in bowel and bladder function and quality of life.
RESULTS: The sample was heterogeneous with respect to age, time since iSCI, initial LE functional limitations, and the presence of deficits in other domains. All participants enrolled completed the study. No incidents of pain or skin response preventing or limiting the intervention were recorded. There were no adverse events regarding falls, autonomic dysreflexia, skin response and cardiovascular events. Our results also indicate that the paired-intervention led to improvements in walking function with changes in the 10 Meter Walk Test and Six-Minute Walk Test that exceed the MCID for SCI and similar improvements in WISCI II post training. Participants reported improvements in quality of life measures, especially as related to increased mobility, independence, and sensation. Surprisingly, some participants reported improvements in voluntary control of bowel and bladder function.
CONCLUSION: These observations suggest that TSCS in combination with therapy is feasible and may be useful to improve functional outcomes for patients with iSCI beyond only walking. TSCS deserves further study as it provides a mechanism to augment functional recovery following spinal pathology.
References
Harkema S, Gerasimenko Y, Hodes J, Burdick J, Angeli C, Chen Y, et al. Effect of epidural stimulation of the lumbosacral spinal cord on voluntary movement, standing, and assisted stepping after motor complete paraplegia: a case study. Lancet. 2011;377:1938-47.
Hofstoetter US, Krenn M, Danner SM, Hofer C, Kern H, McKay WB, et al. Augmentation of Voluntary Locomotor Activity by Transcutaneous Spinal Cord Stimulation in Motor-Incomplete Spinal Cord-Injured Individuals: Augmentation of Locomotion by tSCS in Incomplete SCI. Artif Organs. 2015;39:E176-E186.
