The objective of this study is to identify how the suppression of reflex function by antispastic agents affects volitional movement in people with incomplete spinal cord injury (SCI). Spastic reflexes are commonly treated using medications or other therapeutic approaches without a good understanding of how the subsequent changes in reflex function affect volitional movements, including gait. This study aims to improve our understanding of how reflexes affect functional movements and the impact that oral medications have on reflex regulation of movement in people with incomplete SCI. We will test the effect of two commonly prescribed antispastic oral medications, baclofen and tizanidine, on the reflex regulation of volitional muscle activity and gait. We expect that reflex excitation contributes to the generation of muscle activity during volitional tasks, and antispastic agents will depress reflexes and reduce muscle activity of the legs during gait. A comparison of the effects of reflexes on volitional movements, including gait, and sensitivity to antispastic agents will be made to gain an improved understanding of how different types of incomplete SCI patients utilize reflex activation of muscles to facilitate movement. We anticipate that subjects with greater weakness might rely heavily on reflexes for the generation of muscle activity during movement, and could be detrimentally affected by antispastic medications. This study has important implications for therapies aimed at restoring movement in SCI and for the treatment of spasticity to improve functional movements.

Public Health Relevance

This research project is expected to have a direct impact on the clinical management of rehabilitation in people with spinal cord injury. The results from this study will provide the guidelines for the use of oral medications to improve functional movement, including walking, in people with incomplete spinal cord injury.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS062982-01A2
Application #
7784830
Study Section
Musculoskeletal Rehabilitation Sciences Study Section (MRS)
Program Officer
Kleitman, Naomi
Project Start
2009-09-20
Project End
2011-08-31
Budget Start
2009-09-20
Budget End
2010-08-31
Support Year
1
Fiscal Year
2009
Total Cost
$394,350
Indirect Cost
Name
Marquette University
Department
Biomedical Engineering
Type
Schools of Engineering
DUNS #
046929621
City
Milwaukee
State
WI
Country
United States
Zip Code
53201
Leddy, Abigail L; Connolly, Mark; Holleran, Carey L et al. (2016) Alterations in Aerobic Exercise Performance and Gait Economy Following High-Intensity Dynamic Stepping Training in Persons With Subacute Stroke. J Neurol Phys Ther 40:239-48
Chua, Matthew C; Hyngstrom, Allison S; Ng, Alexander V et al. (2014) Relative changes in ankle and hip control during bilateral joint movements in persons with multiple sclerosis. Clin Neurophysiol 125:1192-201
Chu, Virginia Way Tong; Hornby, Thomas George; Schmit, Brian David (2014) Effect of antispastic drugs on motor reflexes and voluntary muscle contraction in incomplete spinal cord injury. Arch Phys Med Rehabil 95:622-32
Holleran, Carey L; Straube, Don D; Kinnaird, Catherine R et al. (2014) Feasibility and potential efficacy of high-intensity stepping training in variable contexts in subacute and chronic stroke. Neurorehabil Neural Repair 28:643-51