Proof-of-concept for Use of Transcutaneous Spinal Stimulation (TSS) With the ExaStim® Stimulation System in Adults With Chronic Ischemic Stroke

Prior treatment

• Other internal metallic objects of unknown or foreign origin (unidentifiable surgical implants, shrapnel, bullet fragments, etc.)
• Botox injections to the upper limb(s) in prior 3 months

Other illness

• Index stroke is hemorrhagic or involves the brainstem, cerebellum, or thalamus, as confirmed by neuroimaging or medical records.
• Acute medical conditions under active treatment that would contraindicate standard rehabilitation including open wounds, unhealed bone fractures, peripheral neuropathies or painful musculoskeletal dysfunction
• Allergy to hydrogel, silicone, latex or other product materials
• Uncontrolled cardiopulmonary disease or hypertension
• Other symptoms that would prohibit use or cause discomfort from stimulation such as hypersensitivity.
• History of more than one stroke episode
• History of uncontrolled epilepsy or seizures
• Unmanaged depression, psychiatric disorders or ongoing substance abuse

Other

• Active implanted medical device for electrical stimulation
• Severe spasticity, MAS grade \>3 (grade 4 only; grade 3 is not excluded by this criterion) in any of the following muscles: shoulder abductors, shoulder flexors, elbow flexors/extensors, wrist flexion, forearm supination or pronation, or finger flexors.
• Subject scores \<20 or \>50 points on the FMA-UE.
• BMI \> 40.0 (morbid obesity)
• Subjects who are pregnant or planned pregnancy during the study. Participants of childbearing potential must agree to effective contraception for the duration of participation.
• Compromised skin in the area for electrode contact (back of neck and/or hip area)
• Presence of ongoing dysphagia or aspiration difficulties.
• Significant sensory impairments. Subjects who score below a 6 out of 12 on the sensory subscale (section H) of the Fugl Meyer Assessment will be excluded.
• Severe contractures of upper extremity(s)
• Severe receptive and/or expressive aphasia limiting communication and understanding of device and interventions
• Participation in another clinical trial that may interfere with this study

• Subject must have a documented diagnosis of a singular unilateral ischemic stroke event confirmed by radiology report.
• Participant is in the chronic stage of neurological recovery, defined as at least 6 months after the unilateral ischemic stroke event.
• Subject is aged 18-75 years
• In the investigators or qualified clinician's judgment, the subject must possess sufficient global cognitive capacity to understand and follow study-related instructions, actively participate in task-specific rehabilitation, and provide informed consent. Cognitive capacity will be supported by the subject's ability to follow a three-step command and demonstrate orientation to person, place, time, and situation (4/4)
• Subject must have a Fugl-Meyer Assessment-Upper Extremity (FMA-UE) score between 20 and 50 (inclusive) at screening.
• Subject must be able to commit to participating in a 17-week study, and be willing to comply with study instructions, agree to make all office and therapy appointments, and complete the entire course of the study
• Subject must be deemed medically stable for intensive physical rehabilitation and transcutaneous electrical stimulation, supported by formal written clearance from their primary care physician or managing neurologist.
• Subject must be able to understand the study, provide informed consent, and complete the applicable HIPAA authorization using IRB-approved procedures. Literacy alone is not an exclusion. IRB-approved accessible consent methods may be used when needed, while the investigator confirms the participant's own understanding, decision-making capacity, and ability to meet study communication requirements.