This study plans to use systems that have been developed by Medtronic to investigate the use of cervical spinal cord stimulation to treat adults with upper limb hemiparesis resulting from a stroke. The spinal cord stimulation (SCS) will be combined with physical training to improve arm and hand motor control. The study is divided into three phases. In the first phase, after baseline assessments, participants will undergo a Physical Training Protocol (PTP) for 6 weeks including 3 sessions of 90 mins/session per week. After receiving the Medtronic implantable system, in Phase 2, they will then repeat the same PTP program in combination with spinal cord stimulation during the entirety of each of the rehabilitation sessions. Finally, in Phase 3, participants will go home, will not be able to use the stimulation at home but will participate in monthly assessments in the laboratory in which the functionality of the Medtronic system and their motor performances will be assessed for up to 6 months.

The main goal for this study is to evaluate safety of the Medtronic system in the stroke population. The second goal of this study is to assess and document the effects of SCS on motor control. More specifically, whether the combination of SCS and physical exercise (PTP+SCS) will improve motor control and reduce impairments, with the goal of optimizing inclusion criteria and outcome measures for future efficacy studies. To achieve this goal, we designed a study based on the rationale that the ramp up PTP phase 1 will bring people to a plateau motor impairment, in consequence any improvement upon this plateaued level should be due to the intervention.

Inclusion Criteria:

1. Experienced an ischemic or hemorrhagic stroke that resulted in arm and hand hemiparesis more than 6 months prior to the time of enrollment (Prior strokes that did not cause upper extremity motor deficits are not exclusionary.)
2. Age 22 to 70 years old
3. Upper extremity motor score higher than 20 and lower than or equal to 45 on the Fugl-Meyer Assessment (FMA) scale
4. FMA upper extremity sensory score higher than 6 points (out of 12 points)
5. The ability to communicate, understand, give appropriate consent and follow two-step commands

Exclusion Criteria:

1. Presence of any serious disease or disorder (ex. Neurological conditions other than stroke, cancer, severe cardiac or respiratory disease, renal failure, etc.) that could affect their ability to participate in this study
2. Considered to be at high-risk of recurrent stroke as evident from their medical history or upon judgment of the study physician
3. Presence of post-stroke central pain, other forms of pain or other constraints such as joint contractures in the paretic arm that are serious enough to prevent or affect the correct execution of the physical training protocol as judged by the study therapist
4. A score on the Short Blessed Test assessment scale lower than 9
5. Female participants of child-bearing age who are pregnant or breastfeeding during the study
6. Participants that cannot suspend their antiplatelets and/or anticoagulant therapy for two weeks around the time of surgery
7. Existence of any implanted medical device that is not MRI safe and/or any active medical devices even if it is MRI safe
8. Implanted spinal fusion and stabilization devices such as plates and rods between the C2 and T3 spinal vertebra
9. Obstructed or restricted epidural spinal canal to the point of hindering or increasing the risk of implant of the spinal leads as judged by the study surgeon upon screening imaging
10. Severe claustrophobia that prevents execution of the required MRI imaging sessions
11. Taking anti-spasticity or anti-epileptic medications
12. T-score higher than 63 on the 18-question Brief Symptoms Inventory (BSI-18) who have undergone discussions with and been deemed unsuitable by the Principal Investigator and a study physician

Potential participants who may be excluded on initial screening may discuss possible medication changes with their physician.

All of the individual participant data collected during the trial, after deidentification, may be shared with other researchers for the purpose of data analysis and collaboration.

Data will become available at the end of the trial upon publication of the first manuscript. Estimation is 2 years from enrollment of first participant.

Data must be directly requested to the PI and will be shared upon completion of necessary data sharing agreement to protect confidential patient information.