Noninvasive Spinal Stimulation in Stroke

Sperimentale: Noninvasive Spinal Stimulation with Gait Training

May receive up to 50 min of locomotion training with transcutaneous spinal cord stimulation. However, the amount of time spent in side-lying locomotion training, treadmill training and overground training will depend on individual tolerance and progression.

Dispositivo: Noninvasive spinal stimulation with gait training

Transcutaneous Spinal Cord Neurostimulator will deliver transcutaneous electrical spinal cord stimulation while subjects perform locomotor activities.

Comparatore attivo: Conventional Gait Training

May receive up to 50 min of locomotion training without transcutaneous spinal cord stimulation. However, the amount of time spent in side-lying locomotion training, treadmill training and overground training will depend on individual tolerance and progression.

Dispositivo: Conventional gait training

May receive up to 50 min of locomotion training without transcutaneous spinal cord stimulation. However, the amount of time spent in side-lying locomotion training, treadmill training and overground training will depend on individual tolerance and progression.

Altro: Healthy Control Group

Participant in the Healthy Control Group will participate in up to 3 assessment sessions in order to obtain comparative data for Spinal Motor Evoked Potentials (MEPs), lower extremity MVC's, sidelying EMG data and overground EMG data

Altro: Healthy control group

Participant in the Healthy Control Group will participate in up to 3 assessment sessions in order to obtain comparative data for Spinal Motor Evoked Potentials (MEPs), lower extremity MVC's, sidelying EMG data and overground EMG data

Change in Gait Symmetry

Participants will ambulate along Gait Rite electronic walkway up to 12 times (3 times per gait speed with and without lower extremity orthotics) to evaluate baseline gait pattern at both their self-selected and safe fast gait speed. The GAITRite electronic walkway contains sensor pads encapsulated in a carpet and connected to a computer. The system can be laid over any flat surface and automates measuring temporal and spatial gait parameters. The GAITRite electronic walkway for the study shall be a minimum of 14 feet long. The GAITRite data capture was chosen as measurement of the patient's overall gait quality.

Change in 10 Meter Walk Test

This test will examine the patient's gait speed. Patients will be directed to walk at their preferred and maximum but safe speed. Patients will be positioned 1 meter before the start line and instructed to walk the entire distance and past the end line approximately 1 meter. The distance before and after the course are meant to minimize the effect of acceleration and deceleration. Time will be recorded using a stopwatch and recorded to the one hundredth of a second (ex: 2.15 sec). The test will be recorded up to 12 times (3 times at each gait speed with and without lower extremity orthotics if safe and appropriate).

Change in 6 Minute Walk Test Using VO2 Analysis

The 6 Minute Walk Test (6MWT) measures the distance a subject can walk indoors on a flat, hard surface in a period of 6 minutes, using assistive devices, as necessary. The test is a reliable and valid evaluation of functional exercise capacity and is used as a sub-maximal test of aerobic capacity and endurance. The test will be used to determine participant's gait efficiency at baseline and at study completion. The walk test is patient self-paced and assesses the level of functional capacity. Patients are allowed to stop and rest during the test, however, the timer does not stop. If the patient is unable to complete the time, the time stopped is noted and reason for stopping prematurely is recorded.

This test will be administered while wearing a portable gas analysis system called the Cosmed K4B2 to measure oxygen consumption. This system measures oxygen consumption (VO2) and Carbon-dioxide production (VCO2) in a breath by breath fashion.

4. Locomotion assessment for intra limb coordination using electromyography (EMG) on GaitRite

Locomotion assessment for inter and intra limb coordination using wearable sensors and EMG sensors. Participants ambulate along Gait Rite electronic walkway up to 12 times (3 times at each gait speed with and without lower extremity orthotics if safe and appropriate) to evaluate gait pattern and lower extremity muscle activity at both self-selected and fast but safe gait speed.

The sensors used will include those available from the BioStampRC Discovery Kit (MC10,Inc.), EMG sensors and custom sensors designed by the John Rogers research group at Northwestern University. The wearable sensors will collect the following information: Biometric data, including electrocardiography (EKG) and electromyography(EMG). Movement data from the limbs including signals from triaxial accelerometers (ACC) and gyroscopes (GYR). The rate of sweating and glucose concentration using microfluidic sweat sensor.

Change in Spinal Motor Evoked Potentials (MEPs)

Spinal Motor Evoked Potentials (MEPs) will be obtained by stimulating between the spinous processes of up to 5 vertebrae with a single pulse. MEPs are the electromyograph responses of the peripheral muscles to electrical stimulation of the spinal cord. MEPs will be used to test the integrity of the motor pathways of the spinal cord.

A Transcutaneous Spinal Cord Neurostimulator (BioStim-5 or NeuroEnabling Stimulator System) will deliver transcutaneous electrical spinal cord stimulation.

Change corticospinal excitability

Transcranial magnetic stimulation (TMS) will be used to assess changes in corticospinal excitability that may occur following repeated transcutaneous spinal stimulation and ambulation training. TMS is a safe, non-invasive, painless method of brain stimulation that widely used to study the physiology of the representations of muscles in the motor cortex in healthy and neurologically disordered individuals. Very short duration (< 1 ms) magnetic pulses are applied via an insulated wire coil placed on the intact scalp overlaying the motor cortical area projecting to a target muscle. Each pulse induces a motor evoked potential (MEP) in a target muscle that can be readily monitored by recording Electromyogram EMG from that muscle.

Change in Fugl-Meyer Assessment of Motor Recovery after Stroke

The purpose of the FMA is to evaluate and measure recovery in post-stroke hemiplegic patients. There are five domains assessed on a 3 point ordinal scale from 0-2. "0" is equal to "cannot perform", "1" is equal to "performs partially", and "2" is equal to "performs fully. The domains for upper and lower extremity motor function will be used.

Change in Stroke Impact Scale-16

Stroke Impact Scale-16 completed by patient to evaluate the impact of the stroke on the person's health and life from the individuals perspective. It is scored from 1-5, 1 signifying a major effect on the individual and 5 signifying little to no effect.

Change Static in Balance

During the static stability test, the participants will be instructed to stand on the force plate as still as possible for up to 60 seconds with their eyes open. After rest, the task will be repeated with the eyes closed. The excursions of the center of pressure (COP) and EMG of leg muscles will be analyzed.

The AMTI Force System from Water Town, MA will be used to assess balance.

Change in Gait Symmetry on Treadmill

Participants will ambulate on the treadmill for up to 10 minutes in order to obtain spatiotemporal measures of gait and to obtain gait kinematics during treadmill locomotion

Change in Dynamic Balance

During the dynamic stability test, the ability to voluntarily displace the COP to a maximum distance without losing balance will be assessed (Limits of stability (LOS) test). The participant will be instructed to lean forward, backward, left, and right, hold the position for ~5 seconds and return back to the initial/center position.

The AMTI Force System from Water Town, MA will be used to assess balance.