Vagus Nerve Stimulation (VNS) in Spinal Cord Injury (SCI) Adaptive Follow-On Study

This study is an open label extension of the SCI EFS clinical trial (NCT04288245) that developed an innovative strategy to enhance recovery of motor and sensory function after neurological injury. The objectives of this study are to provide continued safety assessment for the investigational ReStore system, and to gain further estimate of the effect of Vagus Nerve Stimulation (VNS) with rehabilitative exercises in three different tracks - upper limb (UL), lower limb (LL) and bladder control (BC) for participants with chronic SCI (Spinal Cord Injury).

A prospective, multi-center, non-randomized, open label extension of the SCI EFS trial (NCT04288245) participants implanted with the investigational ReStore Device for VNS Therapy. Following the completion of Phase 2 of the SCI EFS study, participants can enroll to one of the three tracks. Under each track, participants will undergo up to 36 sessions of rehabilitative exercises self-paced by participants with targeted completion of 3 sessions per week. Evaluations will be administered at the beginning and end of each track (additional progress checks may be conducted, as required by the staff) to monitor participant progress. Upon completion of a paradigm, participants can choose to re-enroll in the same or a different track. Adverse events will be documented and assessed throughout the trial.

Eligibility Criteria:
General Inclusion Criteria:

* Completed phase 2 of the SCI EFS study (NCT04288245)
* Willing to comply with procedures for the entire duration of the study
* Has not had their VNS device explanted

General Exclusion Criteria:

* Any medical condition or other circumstances that might interfere with their ability to return for follow-up visits in the judgment of the Investigator
* Any condition which would preclude adequate evaluation of device's safety and performance in the judgment of the Investigator
* Individuals who have a change in medical condition or health status such that they would meet the exclusion criteria of the EFS
* Concomitant clinically significant brain injuries
* Receiving any other therapy that would interfere with VNS
* Females of childbearing potential who are either pregnant, lactating, heterosexually active, or planning to become pregnant or heterosexually active during study participation; and who are not using, or will not agree to use medically acceptable birth control methods
* Psychiatric disorders, psychosocial, and/or cognitive impairment that would interfere with study participation, as assessed by medical evaluation
* Participants with a current or past: (a) medical (psychiatric, non-psychiatric) condition, disease, disorder, injury, or disability\*; or (b) non-medical situation or circumstance that, in the opinion of the principal investigator, study participation:
* may pose a significant or undue risk to the person;
* make it unlikely the person will complete all the study requirements per protocol; or
* may adversely impact the integrity of the data or the validity of the study results
* Participation in other interventional clinical trial
* Participants with active neoplastic disease.
* Participants with significant local circulatory problems, (e.g. thrombophlebitis and lymphedema, and clinically-significant hypotension or bradycardia).
* Participants with any medical condition or other circumstances that might interfere with their ability to return for follow-up visits in the judgment of the Investigator.
* Any condition which, in the judgment of the Investigator, would preclude adequate evaluation of device's safety and performance.
* Aphasia and other cognitive deficits may be present but participants will be excluded if are unable to understand the potential risks and benefits of the study or personally provide informed consent.
* A recent history of syncope
* A recent history of dysphagia
* Currently require, or are likely to require diathermy
* Significant respiratory issues that would interfere with participation
* Non-English speaking
* Patients who are acutely suicidal and/or have been admitted for a suicide attempt
* As determined by the principal investigator, is under current incarceration or legal detention

UL Inclusion Criteria:

* Provision of signed and dated informed consent form
* Access to reliable communication and internet connections (for those intending to complete sessions at home)
* Willing and able to comply with the study protocol
* Access to reliable communication and internet connections (for those intending to complete sessions at home)

UL Exclusion Criteria:

- Concurrent participation in another active interventional trial or participation in an active interventional trial within 7 days prior to enrollment

LL Inclusion Criteria:

* Ambulatory with gait impairment
* Provision of signed and dated informed consent form
* Access to reliable communication and internet connections (for those intending to complete sessions at home)
* Willing and able to comply with the study protocol

LL Exclusion Criteria:

- Concurrent participation in another active interventional trial or participation in an active interventional trial within 7 days prior to enrollment

BC Inclusion Criteria:

* Issues with urinary function arising from SCI, with partial voluntary initiation of voiding
* Intermittent catheterization for bladder management
* Provision of signed and dated informed consent form
* Access to reliable communication and internet connections (for those intending to complete sessions at home)
* Willing and able to comply with the study protocol

BC Exclusion Criteria:

* Concurrent participation in another active interventional trial or participation in an active interventional trial within 7 days prior to enrollment
* Indwelling catheter use
* Participants with a history of severe or recurrent autonomic dysreflexia
* Technical limitations that would preclude bladder ultrasonography assessments
* Medical history that would preclude adequate evaluation of urologic outcomes