Influence of Wearable Intensive Nerve Stimulation on Spasticity and Function in Persons With Spinal Cord Injury

Spasticity is muscle spasms, bouncing (clonus) or stiffness that can negatively impact the quality of life of people with spinal cord injury (SCI). In people with spinal cord injury, spasticity can limit muscle control of the arms and hands and cause pain, discomfort, and frustration. Transcutaneous electrical stimulation has been shown to reduce spasticity after SCI. However, this type of stimulation's effects during prolonged, at-home use has not been well studied. Additionally, traditional stimulation techniques are often only available in the clinic. Therefore, this study aims to identify if wearable intensive nerve stimulation decreases spasticity in the legs of people with SCI, and if this intervention is usable and desirable to individuals with SCI.

Involuntary muscle activation, also referred to as spasticity is a common characteristic of spinal cord injuries. It can present as stiffness, clonus, and spasms that can impact a person's ability to perform daily tasks. Over half of individuals with spinal cord injuries that have spasticity report medication alone does not control the spasticity. Because of this clinical research is investigation different ways to manage spasticity.

Stretching and vibration have demonstrated the ability to reduce spasticity but only for short periods of time requiring repeated use of the intervention. Additionally, vibration devices are not very practical to implement at home due to their high cost. Due to these factors, a solution that could be used multiple times a day and remains cost effective is needed.

Transcutaneous electrical stimulation (TENS) has also demonstrated effectiveness in reducing spasticity after one session but shows greater benefit when it is able to be used for multiple sessions. A wearable intensive nerve stimulator (WINS) device has been shown to be safe for daily wear which makes it a feasible solution to address spasticity at home. Research has not yet looked at the efficacy of using the WINS device for spasticity and this study proposes to begin to fill that gap.

Eligibility Criteria:
Inclusion Criteria:

* Be 18-65 years of age
* Have sustained cervical or thoracic SCI at least 6 months prior to initiating participation in study
* Any ISNCSCI severity classification (A, B, C, or D)
* Have self-reported spasticity and at the time of screening demonstrate an FSE angle of ≤ 75 degrees on the pendulum test or ≥ 4 beats of clonus on the drop test
* May participate if utilizing oral prescription medications for control of spasticity
* Ability and willingness to consent and authorize use of personal health information

Exclusion Criteria:

* Severe contractures of the leg/foot to be stimulated (decided during pre-assessment) that limit passive movement of the hip, knee, or ankle more than 50% of normal range of motion or presence of other orthopedic pathology that would adversely influence participation in the protocol
* Any implanted catheter such as but not limited to CSF shunt, baclofen pump, or the presence of a pacemaker, implanted automatic internal cardioverter defibrillator (AICD, other cardiac implants and or conditions)
* Severe pain or hypersensitivity of the leg to be stimulated (decided during pre-assessment)
* Uncontrolled edema of the leg to be stimulated (decided during pre-assessment)
* Current pregnancy
* Lumbar spinal cord injury level
* Inability or unwillingness to consent and authorize use of personal health information