Safety and Feasibility of Paired Vagus Nerve Stimulation With Rehabilitation for Improving Upper Extremity Function in People With Cervical Spinal Cord Injury

Purpose

The purpose of this study is to determine the safety and feasibility of pairing vagus nerve stimulation (VNS) with rehabilitation and to determine the efficacy of pairing VNS with rehabilitation.

Condition

  • Cervical Spinal Cord Injury

Eligibility

Eligible Ages
Over 18 Years
Eligible Genders
All
Accepts Healthy Volunteers
No

Inclusion Criteria

  • a diagnosis of traumatic incomplete (AIS B-D) cervical spinal cord injury (C8 and above) - at least 12 months post-traumatic SCI - demonstrate some residual movement in the upper limb (e.g., able to perform pinch movement with thumb and index finger) - meet all clinical criteria for the surgical VNS implantation as determined by the PI, neurosurgeon, and anesthesiologist.

Exclusion Criteria

  • non-traumatic SCI, injury - presence of ongoing dysphasia or aspiration difficulties - evidence of vagus pre-existing vocal cord paralysis as determined with laryngoscopy procedure - participants with prior left-sided anterior cervical surgery who exhibit too much of scar tissue at the surgery site which will be determined by neurosurgeon - concomitant clinically significant brain injury - history of prior injury to a vagus nerve - receiving medication that may significantly interfere with the actions of VNS on neurotransmitter systems at study entry - other comorbidities or complications that will hinder or contraindicate surgical procedure - medical or mental instability - pregnancy or plans to become pregnant during the study period.

Study Design

Phase
N/A
Study Type
Interventional
Allocation
Randomized
Intervention Model
Parallel Assignment
Primary Purpose
Treatment
Masking
Triple (Participant, Investigator, Outcomes Assessor)

Arm Groups

ArmDescriptionAssigned Intervention
Experimental
Treatment group 		Participants in the treatment group will receive 18 goal-directed upper extremity rehabilitation therapy sessions with paired VNS over six weeks. Followed by 90 days home exercise program.
  • Device: Active VNS
    An implantable system consisting of an implantable neurostimulator (model 1001 Implantable Pulse Generator (IPG)) and an implantable lead and electrode (Model 30000 VNS lead) will be used. An external system consisting of an external controller (Model 2000 Wireless Transmitter) and an external software system (computer and Model 4001 Microtransponder SAPS® software) will provide clinical control of settings for the implantable pulse generator (IPG) . All VNS devices (Vivistim System® ) will be provided as a donation by Microtransponder Inc. The device is programmed to stimulate for 0.5s on each button push. After surgical recovery, participants will receive five stimulations in reducing strength (starting at 0.8mA and then reducing to 0.1mA each step) at the beginning of each therapy session, followed by stimulation (0.8 mA)
  • Other: Arm rehabilitation
    . The rehabilitation therapy involves arm and hand exercises with objects. The therapist will select these exercises based on movement abilities. Tasks will be selected from six functional task categories: reach and grasp, gross movement, object flipping, simulated eating tasks, inserting objects, and opening containers. Approximately 30-50 repetitions will be performed in each category. On average, 300-500 repetitions will be performed during each session within 1.5-2hours.
Sham Comparator
Control Group 		Participants in the control group will receive 18 goal-directed upper extremity rehabilitation therapy sessions with sham VNS over six weeks. Followed by 90 days home exercise program.
  • Device: Sham VNS
    An implantable system consisting of an implantable neurostimulator (model 1001 Implantable Pulse Generator (IPG)) and an implantable lead and electrode (Model 30000 VNS lead) will be used. An external system consisting of an external controller (Model 2000 Wireless Transmitter) and an external software system (computer and Model 4001 Microtransponder SAPS® software) will provide clinical control of settings for the implantable pulse generator (IPG) . All VNS devices (Vivistim System® ) will be provided as a donation by Microtransponder Inc. The device is programmed to stimulate for 0.5s on each button push. After surgical recovery, participants will receive five stimulations in reducing strength (starting at 0.8mA and then reducing to 0.1mA each step) at the beginning of each therapy session, followed by stimulation (0 mA)
  • Other: Arm rehabilitation
    . The rehabilitation therapy involves arm and hand exercises with objects. The therapist will select these exercises based on movement abilities. Tasks will be selected from six functional task categories: reach and grasp, gross movement, object flipping, simulated eating tasks, inserting objects, and opening containers. Approximately 30-50 repetitions will be performed in each category. On average, 300-500 repetitions will be performed during each session within 1.5-2hours.

Recruiting Locations

The University of Texas Health Science Center at Houston
Houston, Texas 77030
Contact:
Radha Korupolu
713-797-5233
Radha.Korupolu@uth.tmc.edu

More Details

Status
Recruiting
Sponsor
The University of Texas Health Science Center, Houston

Study Contact

Radha Korupolu, MD
713-797-5233
Radha.Korupolu@uth.tmc.edu

Detailed Description

The current study will evaluate the safety and feasibility of a novel rehabilitation protocol to improve upper limb motor recovery in adults with incomplete cervical SCI. In this double-blinded, randomized, placebo-controlled pilot trial, 8 adults (above 18 years) with cervical SCI will be randomly assigned in a 1:1 ratio to active VNS paired with rehabilitation or control VNS paired with rehabilitation. All participants will be implanted with a VNS device and randomized to receive either active VNS (0.8mA) or control VNS (0.0 mA) paired with upper limb rehabilitation. All participants will receive three 1.5-hour sessions per week for 6 weeks of in-clinic therapy, followed by a daily, 30 minutes home therapy program for 90 days. The rehabilitation therapy involves repetitive, progressive, task-specific exercises adjusted to the participant's functional level. Participants, assessors, and therapists will maintain blinding until the completion of this phase. After 90 days, in phase II, participants in the control VNS group will cross over to receive active VNS paired with rehabilitation. Safety and feasibility measures are the primary outcomes of this study. Safety measures will include the incidence of surgical and VNS therapy-related events. Feasibility metrics include reporting attrition rate and compliance rate with both in-clinic therapy sessions and home exercise programs. To measure efficacy, change in Graded and Redefined Assessment of Strength, Sensibility, and Prehension from baseline to immediately after 6-week in-clinic treatment and 90-day assessment will be analyzed. Additional clinical outcomes include the Toronto Rehab Institute Hand Function Test, Capabilities of Upper Extremity Questionnaire, spinal cord injury independence self-care measure, and spinal cord injury quality of life. The results of this study will provide valuable information on safety and feasibility and insight into the efficacy of pairing VNS with rehabilitation in people with SCI. Knowledge obtained from this study will lay the groundwork for future large randomized control trials to assess the dosing and effectiveness of pairing VNS with rehabilitation.