Stroke
Conditions
Keywords
Stroke, Gait Disorders, Neurologic, Gait Analysis, Neuromuscular Control, Rehabilitation, Stroke, Exoskeleton Device, Biomechanics
Brief summary
Stroke survivors often experience impaired neuromechanical control that limits walking speed and quality, particularly due to deficits in paretic propulsion. This study aims to identify patient-specific neuromechanical locomotor control strategies, link them to biomechanical gait impairments, and investigate how these strategies influence responses to soft robotic exosuit assistance of paretic propulsion and ground clearance during walking. The study focuses on adults who are more than six months post-stroke and have observable gait deficits. The main questions are: 1. How do neuromechanical control patterns (i.e., electromyography-measured muscle coordination) affect walking speed, quality, and gait biomechanics after stroke? 2. Do individuals with distinct neuromechanical patterns respond differently to robotic exosuit-assisted gait rehabilitation? Researchers will compare walking performance without and with robotic exosuit assistance to determine whether tailoring exosuit-assisted gait intervention to patient-specific neuromechanical profiles can lead to greater improvements in walking function. Participants will complete treadmill and overground walking assessments instrumented with motion capture, EMG, and force plates, performing one trial without assistance and two trials with robotic exosuit assistance delivered at different assistance onset timings, from which a preferred assistance setting will be identified. The walking trial associated with the preferred assistance setting will be used for primary analyses.
Interventions
DEVICEWalking with robotic ankle assistance
Subjects will complete two trials of 3-minute treadmill walking with active robotic exosuit assistance, from which a preferred assistance profile will be identified. The treadmill walk associated with the preferred profile will be used for primary analyses.
Sponsors
Boston University Charles River Campus
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE
Intervention model description
Participants will complete a 3-minute treadmill walking trial without robotic exosuit assistance and then complete two trials with different assistance profiles from which a preferred profile will be identified.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* At least 18 years old * \>6 months post-stroke * Observable gait deficits * Able to walk overground and on a treadmill without body-weight support * Able to communicate clearly with investigators and follow instructions * Able to fit the exosuit components, including height between 4'8" and 6'7", weight \< 264lbs, neutral ankle dorsiflexion during standing.
Exclusion criteria
* Comorbidities besides stroke that impair walking (musculoskeletal, cardiovascular, pulmonary, or neurological) * Severe pain, neglect, hemianopia, or aphasia limiting comprehension * Unexplained dizziness or more than 2 falls in the previous month * Inability to communicate (as assessed by a licensed physical therapist) * Inability to wear the exosuit due to conditions that require medical management, such as open wounds or broken skin, or as assessed by a licensed physical therapist.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Dynamic Motor Control Index (DMCI) | Baseline, Assisted (on average 1-2 hours) | Difference in neuromuscular control quality compared to normative data with and without exosuit |
| Correlation Between Propulsion and Weight-Acceptance Motor Modules (Temporal) | Baseline, Assisted (on average 1-2 hours) | Difference in the merging of motor module structures quantified by correlation coefficient between the propulsion temporal module and weight-acceptance temporal module, computed from EMG data by non-negative matrix factorization, with and without exosuit |
| Correlation Between Weight-Acceptance and Swing-Limb Deceleration Motor Modules (Temporal) | Baseline, Assisted (on average 1-2 hours) | Difference in the merging of motor module structures quantified by correlation coefficient between the weight-acceptance temporal module and swing-limb deceleration temporal module, computed from EMG data by non-negative matrix factorization, with and without exosuit |
| Variance Accounted For (VAF) by Four Muscle Synergies | Baseline, Assisted (on average 1-2 hours) | Difference in the variance in muscle activation accounted for by the 4-synergy model, measuring the quantitative shift in muscle coordination complexity with and without exosuit (%) |
| Paretic Propulsion | Baseline, Assisted (on average 1-2 hours) | Difference in anterior-posterior ground reaction force with and without exosuit (N) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Joint Angle | Baseline, Assisted (on average 1-2 hours) | Difference in joint angles computed using inverse dynamics, including ankle, knee, and hip angles, with and without exosuit (degrees) |
| Joint Torque | Baseline, Assisted (on average 1-2 hours) | Difference in joint torques computed using inverse dynamics, including ankle, knee, and hip torques, with and without exosuit (Nm/kg) |
| Joint Power | Baseline, Assisted (on average 1-2 hours) | Difference in joint power computed using inverse dynamics, including ankle, knee, and hip power, with and without exosuit (W/kg) |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORLouis N Awad, PT, DPT, PhD
Boston University Charles River Campus
Outcome results
None listed