Adaptive Hip Exoskeleton for Stroke Gait Enhancement

Study Overview
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Brief Summary
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This work will focus on new algorithms for robotic exoskeletons and testing these in human subject tests. Individuals who have previously had a stroke will walk while wearing a robotic exoskeleton on a specialized treadmill. The study will compare the performance of the advanced algorithm with not using the device to determine the clinical benefit.

Detailed Description
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The focus of this work is a proposed novel artificial intelligence (AI) system to self-adapt control policy in powered exoskeletons to aid deployment systems that personalize to individual patient gait. The investigators hypothesize that walking speed will improve with the use of the self-adaptive control policy system. Individuals post stroke have a broad range of mobility challenges including asymmetric gait, substantially decreased SSWS, and reduced stability, and therefore have greatly impaired overall mobility independence in the community. The investigators expect the proposed novel controller, capable of personalization to such variable and asymmetric gait patterns, will have significant benefits towards increasing community independence and mobility for patients post stroke. 12 patients post stroke will be fit with the hip exoskeleton and proceed to walk at varying speeds and inclines on a Motek CAREN system while the investigators measure self-selected walking speed. The self-adaptive system will be compared directly to a best-on-average control policy (non-adaptive) as well as to a 'standard of care' baseline. This baseline will be walking with no exoskeleton plus any clinically prescribed passive orthoses. The investigators expect the self-adaptive system to learn the control policy that best matches the patient's gait patterns, thus yielding advantages in walking speed.

Official Title
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Powered Hip Exoskeleton for Stroke Survivors With Gait Impairment

Conditions
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Stroke

Intervention / Treatment
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* Device: Robotic hip exoskeleton


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Previous history of stroke with a physician's approval to safely perform the experimental activities. The stroke must have occurred at least 6 months prior to study involvement. Aged between 18-85 years of age. Score greater than 17 on the mini-mental state examination (MMSE). Able to sit unsupported for minimum of 30 seconds. Able to follow a 3 step command. Must be able to walk without support (a rail as needed is allowed), with a walking speed of at least 0.4 m/s (limited community ambulatory speed). Must be able to walk for at least 6 minutes. Must be willing and able to participate in a 1-4 hour experiment, with breaks enforced regularly and as needed . Must be able to transfer (sit-to-stand and stand-to-sit) with no external support (arm rests support allowed). Must be able to ambulate over small slopes (3 degrees) and a few steps (6 steps). Exclusion Criteria: Loss of sensation in the legs, a complete spinal cord injury, history of concussion in the last 6 months, history of any severe cardiovascular conditions, severe arthritis, or orthopedic problems that would limit full participation in the study. Diagnosis of other neurological disorders such as Parkinson's disease, Amyotrophic Lateral Sclerosis (ALS), Multiple Sclerosis (MS), dementia, history of head trauma which is not fully resolved (per participant report), lower extremity amputation, non-healing ulcers of a lower extremity, renal dialysis or end state liver disease, legal blindness or severe visual impairment. Use of a pacemaker or have metal implants in the head region or medications that lower seizure thresholds. Lastly, if you are participating in another clinical study and/or your physical condition is limited to do different tasks, in the opinion of the Principal Investigator (PI), would likely affect the study outcome or confound the results, you will be excluded from the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Interventional Model Description: The model used is a repeated measures single arm study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Powered Hip Exoskeleton for Stroke Assistance<br>This study will be conducted on a sample population of stroke subjects (single arm). Each subject will test with each condition of the exoskeleton (repeated measures). | Device: Robotic hip exoskeleton<br>* The intervention is an experimental robotic hip exoskeleton that has been previously developed by the team. It is used to improve walking gait performance.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Self-Selected Walking Speed | This measures the individuals preferred overground walking speed which indicates their physical capability with a device. | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Stroke