Activity-Dependent Transspinal Stimulation in SCI
- Conditions
- Paraplegia, SpasticTetraplegia/TetraparesisSpinal Cord InjuriesParaplegia, Spinal
- Interventions
- Device: Robotic gait training and high-frequency transspinal stimulationOther: Robotic gait trainingDevice: Robotic gait training and low-frequency transspinal stimulation
- Registration Number
- NCT03669302
- Lead Sponsor
- City University of New York
- Brief Summary
Robotic gait training is often used with the aim to improve walking ability in individuals with Spinal Cord Injury. However, robotic gait training alone may not be sufficient. This study will compare the effects of robotic gait training alone to robotic gait training combined with either low-frequency or high-frequency non-invasive transspinal electrical stimulation. In people with motor-incomplete SCI, a series of clinical and electrical tests of nerve function will be performed before and after 20 sessions of gait training with or without stimulation.
- Detailed Description
People with spinal cord injury (SCI) have motor dysfunction that results in substantial social, personal, and economic costs. Robotic gait training is often used with the aim to improve walking ability in these individuals. Investigators recently reported that robotic gait training reorganizes spinal neuronal circuits, improves motor activity, and contributes substantially to recovery of walking ability in people with motor incomplete SCI. However, pathological muscle tone and abnormal muscle activation patterns during assisted stepping were still evident after multiple sessions of robotic gait training. Locomotor training alone may thus be insufficient to strengthen weak neuronal synapses connecting the brain with the spinal cord or to fully optimize spinal neural circuits. On the other hand, spinal cord stimulation increases sprouting and plasticity of axons and dendrites in spinalized animals. Furthermore, transcutaneous spinal cord stimulation (termed here transspinal stimulation) in people with SCI can evoke rhythmic leg muscle activity when gravity is eliminated. A fundamental knowledge gap still exists on induction of functional neuroplasticity and recovery of leg motor function after repetitive thoracolumbar transspinal stimulation during body weight supported (BWS) assisted stepping in people with SCI. The central working hypothesis in this study is that transspinal stimulation delivered during BWS-assisted stepping provides a tonic excitatory input increasing the overall responsiveness of the spinal cord and improving motor output. The investigators will address 3 specific aims: Establish induction of neuroplasticity and improvements in leg sensorimotor function in people with motor incomplete SCI when transspinal stimulation is delivered during BWS-assisted stepping at low frequencies (0.3 Hz; Specific Aim 1) and at high frequencies (30 Hz; Specific Aim 2), and when BWS-assisted step training is administered without transspinal stimulation (Specific Aim 3). In all groups, outcomes after 20 sessions will be measured via state-of-the-art neurophysiological methods. Corticospinal circuit excitability will be measured via transcranial magnetic stimulation motor evoked potentials in seated subjects (Aims 1A, 2A, 3A). Soleus H-reflex and tibialis anterior flexor reflex excitability patterns will be measured during assisted stepping (Aims 1B, 2B, 3B). Sensorimotor function will be evaluated via standardized clinical tests of gait and strength (Aims 1C, 2C, 3C). Additionally, poly-electromyographic analysis of coordinated muscle activation will be measured in detail. It is hypothesized that transspinal stimulation at 30 Hz during assisted stepping improves leg motor function and decreases ankle spasticity more compared to 0.3 Hz. It is further hypothesized that transspinal stimulation at 30 Hz normalizes the abnormal phase-dependent soleus H-reflex and flexor reflex modulation commonly observed during stepping in people with motor incomplete SCI. To test the project hypotheses, 45 people with motor incomplete SCI will be randomly assigned to receive 20 sessions of transspinal stimulation at 0.3 or 30 Hz during BWS-assisted stepping or 20 sessions of BWS-assisted stepping without transspinal stimulation (15 subjects per group). Results from this research project will advance considerably the field of spinal cord research and change the standard of care because there is great potential for development of novel and effective rehabilitation strategies to improve leg motor function after motor incomplete SCI in humans.
Recruitment & Eligibility
- Status
- TERMINATED
- Sex
- All
- Target Recruitment
- 10
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Robotic gait training & high-frequeny transspinal stimulation. Robotic gait training and high-frequency transspinal stimulation Robotic gait training will be administered along with non-invasive transspinal stimulation over the thoracolumbar region during assisted stepping at high frequency (30 Hz). Robotic gait training Robotic gait training Robotic gait training only Robotic gait training & low-frequeny transspinal stimulation. Robotic gait training and low-frequency transspinal stimulation Robotic gait training will be administered along with non-invasive transspinal stimulation over the thoracolumbar region during assisted stepping at low frequency (0.3 Hz).
- Primary Outcome Measures
Name Time Method Plasticity of spinal neuronal circuits 3 years Neurophysiological tests probing spinal reflex excitability will be measured before and after each intervention by posterior tibial and sural nerves stimulation during Lokomat-assisted stepping depicting the amplitude modulation of the soleus H-reflex and tibialis anterior flexor reflex.
Plasticity of cortical and corticospinal neuronal circuits 3 years Neurophysiological tests probing cortical and corticospinal excitability will be measured before and after the intervention. Single-pulse transcranial magnetic stimulation (TMS) will be used to assemble the recruitment curve of motor evoked potentials, and paired-pulse TMS will be used to probe changes in cortical inhibitory and facilitatory neuronal circuits.
- Secondary Outcome Measures
Name Time Method Spasticity 3 years Tardieu scale
Senorimotor leg motor function 3 years Manual muscle test and leg sensation based on American Spinal Injury Association guidelines.
Walking function 3 years Two-minute walk test and 10 meter timed test.
Trial Locations
- Locations (2)
Department of Physical Therapy, Motor Control and NeuroRecovery Laboratory
🇺🇸Staten Island, New York, United States
Veterans Affairs Medical Center
🇺🇸Bronx, New York, United States