Neuromechanical Mechanisms of Exosuit-assisted Gait Rehabilitation After Stroke

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.

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.