Neuromechanical Gait Assist for Stroke Recovery

Overseen By Lisa M Lombardo, MPT

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: VA Office of Research and Development

Disqualifiers: Severe knee tone, Cardiac arrhythmias, Parkinson's, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 33

5 Participants Needed

Trial Summary

Do I need to stop taking my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the Neuromechanical Gait Assist treatment for stroke recovery?

Research shows that powered exoskeletons, which are similar to the Neuromechanical Gait Assist, can improve walking speed in stroke patients by providing assistance to the hips. Additionally, electromechanical-assisted gait training, which is a component of the Neuromechanical Gait Assist, has been found to be as effective as traditional physical therapy in improving walking function after a stroke. ^{1 2 3 4 5}

Is the Neuromechanical Gait Assist generally safe for humans?

Powered exoskeletons, like the Neuromechanical Gait Assist, have been approved by regulatory bodies, but there are still risks such as skin injuries, musculoskeletal issues, and blood pressure changes. More structured reporting and risk management are needed to ensure safety. ^{4 5 6 7 8}

How is the Neuromechanical Gait Assist treatment different from other stroke recovery treatments?

The Neuromechanical Gait Assist treatment is unique because it uses a robotic system that adapts to the specific muscle activation patterns of stroke patients, helping to improve their walking by mimicking healthy movement patterns. This approach is different from traditional therapies as it focuses on personalized, dynamic assistance based on the patient's own neuromuscular signals. ^{1 9 10 11 12}

What is the purpose of this trial?

Objective: The goal of this study is to implement and test a neuro-mechanical gait assist (NMGA) device to correct walking characterized by muscle weakness, incoordination or excessive tone in Veterans with hemiparesis after stroke that adversely affects their ability to walk, exercise, perform activities of daily living, and participate fully in personal, professional and social roles. Research Plan: A prototype NMGA device will be used to develop a finite state controller (FSC) to coordinate each user's volitional effort with surface muscle stimulation and motorized knee assistance as needed. Brace mounted sensors will be used to develop a gait event detector (GED) which will serve the FSC to advance through the phases of gait or stair climbing. In addition, a rule-base intent detection algorithm will be developed using brace mounted sensors and user interface input to select among various functions including walking, stairs climbing, sit-to-stand and stand-to-sit maneuvers. The FSC controller tuning and intent algorithm development and evaluation will be on pilot subjects with difficulty walking after stroke. Outcome measures during development will provide specifications for a new prototype NMGA design which will be evaluated on pilot subjects to test the hypothesis that the NMGA improves walking speed, distance and energy consumption of walking. These baseline data and device will be used to design a follow-up clinical trial to measure orthotic impact of NMGA on mobility in activities of daily living at home and community. Methodology: After meeting inclusion criteria, pilot subjects will undergo baseline gait evaluation with EMG activities of knee flexors and extensors, ankle plantar and dorsiflexors and isokinetic knee strength and passive resistance. They will be fitted with a NMGA combining a knee-ankle-foot-orthosis with a motorized knee joint and surface neuromuscular stimulation of plantar- and dorsi- flexors, vasti and rectus femoris. Brace mounted sensor data will be used for gait event detector (GED) algorithm development and evaluation. The GED will serve the FSC to proceed through phases of gait based on supervisory rule-based user intent recognition algorithm detected by brace mounted sensors and user input interface. The FSC will coordinate feed-forward control of tuned stimulation patterns and closed-loop controlled knee power assist as needed to control foot clearance during swing and stability of the knee during stance. Based on data attained during controller development and evaluation, a new prototype NMGA will be design, constructed and evaluated on pilot subjects to test the hypothesis that a NMGA device improves safety and stability, increases walking speed and distance and minimizes user effort. Clinical Significance: The anticipated outcome is improved gait stability with improved swing knee flexion, thus, increasing the safety and preventing injurious falls of ambulatory individuals with hemiplegia due to stroke found in large and ever-increasing numbers in the aging Veteran population. Correcting gait should lead to improved quality of life and participation.

Research Team

Ronald Triolo, PhD

Principal Investigator

Louis Stokes VA Medical Center, Cleveland, OH

Eligibility Criteria

This trial is for Veterans with hemiparesis after a stroke, who can walk at least 10ft with some help and have enough upper body function to use a cane. They should be over 6 months post-stroke and have specific ranges of motion in their hips and ankles. People with severe muscle tone issues, joint contractures, infections, pregnancy, certain heart conditions or severe cognitive impairments cannot participate.

Inclusion Criteria

I can use a cane with my arms.

I can move my ankle up to a neutral position without help when my leg is straight.

I can lift my knee toward my chest at least halfway.

Exclusion Criteria

My knee is very stiff, needing a lot of force to bend.

I have stiffness in my ankles and hips that limits their movement.

Pregnancy

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Baseline Testing

Initial testing to determine participants' impairment level and walking ability prior to controller development and training with the device

2 weeks

2 visits (in-person)

NMGA Fitting and Tuning

Participants are fitted with the NMGA device and appropriate stimulation patterns are determined to assist walking

2 weeks

2 sessions (in-person)

Controller Development

Development and optimization of the controller to coordinate NMGA assistance with walking ability

8 weeks

Up to 16 sessions (in-person)

Gait Training

Training sessions to use the device for walking, stair climbing, and sit-to-stand transitions

6 weeks

6 sessions (in-person)

Post-Training Assessment

Assessments repeated to test the hypothesis that walking with the NMGA enhances walking speed, endurance, metabolic consumption, and gait symmetry

2 weeks

Up to 6 sessions (in-person)

Follow-up

Participants are monitored for safety and effectiveness after training

up to 1 year

Treatment Details

Interventions

• Neuromechanical Gait Assist

Trial Overview The study tests a new device called NMGA that helps correct walking problems caused by strokes. It combines leg braces with motorized knee joints and electrical muscle stimulation. The goal is to improve walking speed, distance covered, energy used when walking, safety and stability.

Participant Groups

Group I: Neuromechanical Gait Assist Experimental Treatment 1 Intervention

All participants will participate in developing controllers to coordinate device assistance with walking ability. Walking will be compared before gait training and after gait training. Walking will be evaluated both with and without device assistance.

Who Is Running the Clinical Trial?

VA Office of Research and Development

Lead Sponsor

Trials

1,691

Recruited

3,759,000+

Findings from Research

Powered hip exoskeletons significantly improved walking speed in stroke patients, with a 17.6% increase using bilateral assistance and an 11.1% increase with unilateral assistance, compared to walking without a device.

Both assistance strategies also enhanced step length for both the affected and unaffected legs, indicating that exoskeletons can effectively improve gait biomechanics and overall mobility post-stroke.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of Bilateral Assistance for Hemiparetic Gait Post-Stroke Using a Powered Hip Exoskeleton. Pan, YT., Kang, I., Joh, J., et al.[2023]

Powered exoskeletons, like the ReWalk™, Indego™, and Ekso™, have been approved as medical devices to help individuals with gait disabilities walk upright, but the understanding of their risks and safety is still developing.

There is a significant need for standardized regulations and awareness of potential risks associated with powered exoskeletons to ensure safe and effective use, as current criteria for their use and reported adverse events vary widely.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Risk management and regulations for lower limb medical exoskeletons: a review. He, Y., Eguren, D., Luu, TP., et al.[2020]

A systematic review of 50 studies involving 985 subjects revealed that adverse events (AEs) occurred in 18 studies, with over 169 device-related AEs reported, primarily soft tissue injuries and musculoskeletal issues, particularly in end-effector and exoskeleton devices.

The most common risks associated with stationary robot-assisted gait training include excessive pressure and shear at the interface between the device and the user, as well as misalignments that increase forces on the musculoskeletal system, highlighting the need for improved reporting and safety measures.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Occurrence and Type of Adverse Events During the Use of Stationary Gait Robots-A Systematic Literature Review. Bessler, J., Prange-Lasonder, GB., Schulte, RV., et al.[2021]

The use of an electromechanical gait trainer combined with functional electrical stimulation (FES) in a 4-week program led to significant improvements in gait performance and functional activities for two patients with acute ischemic stroke.

Both patients maintained their improvements in various measures of mobility and balance, such as the Barthel Index and Berg Balance Scale, even 6 months after the intervention, indicating long-term benefits of this rehabilitation approach.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gait training of patients after stroke using an electromechanical gait trainer combined with simultaneous functional electrical stimulation. Tong, RK., Ng, MF., Li, LS., et al.[2016]

References

1. England pubmed.ncbi.nlm.nih.gov

An observational report of intensive robotic and manual gait training in sub-acute stroke. [2022]

2. United States pubmed.ncbi.nlm.nih.gov

Effects of Bilateral Assistance for Hemiparetic Gait Post-Stroke Using a Powered Hip Exoskeleton. [2023]

3. England pubmed.ncbi.nlm.nih.gov

Efficacy of electromechanical-assisted gait training on clinical walking function and gait symmetry after brain injury of stroke: a randomized controlled trial. [2022]

4. Sweden pubmed.ncbi.nlm.nih.gov

Electromechanical-assisted gait training after stroke: a systematic review comparing end-effector and exoskeleton devices. [2022]

5. United States pubmed.ncbi.nlm.nih.gov

Driving electromechanically assisted Gait Trainer for people with stroke. [2019]

6. New Zealand pubmed.ncbi.nlm.nih.gov

Risk management and regulations for lower limb medical exoskeletons: a review. [2020]

7. Switzerland pubmed.ncbi.nlm.nih.gov

Occurrence and Type of Adverse Events During the Use of Stationary Gait Robots-A Systematic Literature Review. [2021]

8. United States pubmed.ncbi.nlm.nih.gov

Gait training of patients after stroke using an electromechanical gait trainer combined with simultaneous functional electrical stimulation. [2016]

9. United States pubmed.ncbi.nlm.nih.gov

Tuning of robotic therapy controllers for stroke gait: Using isometrically constrained EMG modular structures. [2020]

10. England pubmed.ncbi.nlm.nih.gov

Electromechanical-assisted training for walking after stroke. [2018]

11. England pubmed.ncbi.nlm.nih.gov

Electromechanical-assisted training for walking after stroke. [2023]

12. England pubmed.ncbi.nlm.nih.gov

Electromechanical-assisted training for walking after stroke. [2023]