Walk Assist Device to Improve Community Ambulation

Not Applicable

Completed

Conditions: Stroke

Interventions: Device: Honda Stride Assist Device ON
Other: No Device Worn

Registration Number: NCT03222505

Lead Sponsor: Shirley Ryan AbilityLab

Brief Summary: The goal of this research study was to examine the immediate effects of a prototype wearable robotic stride management assist device (SMA) designed by Honda R\&D® on clinical walking performance, walking energetics, gait kinematics and corticospinal excitability in individuals with stroke.

Detailed Description: The goal of this research study was to examine the immediate effectiveness of a prototype wearable robotic stride management assist device (SMA) designed by Honda R\&D on clinical walking performance, walking energetics, gait kinematics and corticospinal excitability in individuals with stroke.

The SMA assists walking by providing a flexion and extension torque assist at the hip joint. The subjects in this study are asked to perform two sets of experiments: one set with the device on and one set with the device turned off. The order in which the subjects performed these sets of experiments is selected randomly. Each set of experiments includes over-ground walking speed and endurance tests, a graded treadmill test with metabolic measures, motion capture and force treadmill analysis, and measures of corticospinal drive using transcranial magnetic stimulation (TMS). The primary outcome to be measured is change in self-selected walking speed with the device on, the secondary outcome measures include metabolic, corticospinal and biomechanical analysis.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 12

Inclusion Criteria

Stroke subjects with a history of unilateral, supratentorial, ischemic or hemorrhage stroke will be recruited, with lesion location confirmed by radiographic findings.
All subjects who score > 10 on the Lower Extremity Motor Score (LEMS) developed previously to measure strength in Spinal Cord Injury (SCI). For the LEMS criteria, preliminary data indicate that subjects with LEMS < 10 in the chronic stages do not recover walking.
All subjects will be required to walk > 10 m over ground without physical assistance at self-selected walking speeds ≤ 0.8 m/s using assistive devices and bracing below the knee as needed. A criterion of 0.8 m/s is utilized to target participants with limited or minimal ambulation in the community. Subjects will be further stratified into those who walk < 0.4 m/s and > 0.4 m/s, identified as household vs. limited community ambulators, respectively.
Range of motion (ankle: -10 to 30 deg, knee: 0 to 90 deg, hip: -10 to 40 deg) consistent with gait;
Medically stable with medical clearance to participate (absence of concurrent illness, including unhealed decubiti, infection, cardiopulmonary disease, osteoporosis, active heterotrophic ossification or peripheral nerve damage in the lower limbs, history of traumatic head injury);
Able to tolerate 30 minutes of upright (standing) position without orthostasis (decrease in blood pressure by 20 mmHg systolic and 10 mmHg diastolic; minimized with ambulatory population);
Must not be undergoing concurrent physical therapy to eliminate effects of additional interventions;
Patients prescribed medications for spasticity will not be excluded from participation but will be asked to maintain current levels of medication or inform the researcher if changes are necessary.

Exclusion Criteria

Women of childbearing potential will not be excluded, although women who are pregnant will be excluded due to potential forces at trunk from body weight support or pelvic assistance;
Significant cardiorespiratory or metabolic disease that may limit exercise participation.
Weights limit > 250 lbs (limit of most counter-weight safety systems).
History of previous orthopedic or neurological conditions which may impair walking.
Exclusion for TMS: pacemaker, metal implants in the head region, history of epilepsy or seizures, skull fractures or skull deficits, concussion within the last 6 months, unexplained recurring headaches, medications that lower seizure threshold, and pregnancy.
Subjects with scores < 23 on the Mini Mental Status Exam will be excluded.

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Treadmill	No Device Worn	-
Overground Walking	No Device Worn	-
Treadmill	Honda Stride Assist Device ON	-
Overground Walking	Honda Stride Assist Device ON	-

Primary Outcome Measures

Name	Time	Method
Change in Peak Treadmill (TM) Velocity Between Device Turned ON and OFF - Self Selected Walking Speed	Day 1	Peak treadmill (TM) velocity: subjects walked on motorized treadmill with harness but no Body Weight Support (BWS). Testing started at 0.5 km/h and was increased in 0.5 km/h increments every 3 minutes until peak TM speed was achieved (identified as ability to sustain speed for ≥1min without stopping the treadmill).
Change in Six Minute Walk Test Between Device Turned ON and OFF - Distance Traveled	Day 1	The 6 Minute Walk Test (6MWT) is a test of endurance, by measuring the distance a subject can walk indoors on a flat, hard surface in a period of 6 minutes, using assistive devices, as necessary.The distance is measured with a measuring wheel. The instructions are "Walk covering as much ground as you can in 6 min. You can stop to sit or stand if needed."

Secondary Outcome Measures

Name	Time	Method
Percent Change in Excitability of Transcranial Magnetic Stimulation (TMS) Rectus Femoris (RF) Between Device ON and Device OFF	Day 1	TMS measurements will involve generating motor evoked potentials (MEP) for each muscle from two different coil positions - 2cm on either side of the vertex. Motor evoked potentials (MEPs) at intensities ranging from 70 - 140% active threshold will be generated for each muscle from each coil position. TMS is a safe, non-invasive, painless method of brain stimulation that has been widely used to study the physiology of the representations of muscles in the motor cortex in healthy and neurologically disordered individuals. A positive percent change in excitability indicates higher excitability in the device-on condition. A negative percent change in excitability indicates higher excitability in the device-off condition.
Change in Percent Excitability of Transcranial Magnetic Stimulation (TMS), Dorsiflexor Tibialis Anterior (TA) Between Device ON and Device OFF	Day 1	TMS measurements will involve generating motor evoked potentials (MEP) for each muscle from two different coil positions - 2cm on either side of the vertex. Motor evoked potentials (MEPs) at intensities ranging from 70 - 140% active threshold will be generated for each muscle from each coil position. TMS is a safe, non-invasive, painless method of brain stimulation that has been widely used to study the physiology of the representations of muscles in the motor cortex in healthy and neurologically disordered individuals. A positive percent change in excitability indicates higher excitability in the device-on condition. A negative percent change in excitability indicates higher excitability in the device-off condition.