Repetitive Nerve Stimulation to Improve Recovery After Stroke

Study Overview
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Brief Summary
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Upper limb paresis is the most common type of post-stroke neurological impairment and a major cause of functional disability. Repetitive peripheral electrical stimulation (RPES) is a novel strategy to improve upper limb motor performance in the post-stroke chronic phase but its effects in the subacute phase are still poorly understood. The objectives of this study are to compare the effects of RPES on motor performance of the upper limb in the subacute and chronic phases of stroke, and to identify the mechanisms underlying this intervention.

Official Title
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Comparison Between Mechanisms Underlying Effects of Repetitive Peripheral Nerve Stimulation on Upper Limb Motor Performance in the Subacute and Chronic Phases After Stroke

Conditions
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Stroke

Intervention / Treatment
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* Device: Repetitive peripheral nerve stimulation
* Device: Sham Repetitive peripheral nerve stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ischemic or hemorrhagic stroke confirmed by computed tomography or magnetic resonance imaging, between 7 days - 3 months before enrollment (subacute phase), and at least 6 months (chronic phase). Ability to perform at least 4 of 7 tasks performed in daily life that is part of the Jebsen-Taylor Test Exclusion Criteria: Anesthesia of the paretic hand. Lesions affecting the motor cortex (hand area). Lesions affecting cerebellum, or cerebellar pathways in the brainstem. Severe spasticity at the paretic elbow, fist or fingers, defined with a score larger than 3 on the Modified Ashworth Scale. Neurological diseases such as Parkinson disease or chronic uncontrolled chronic disease such as cancer or cardiac insufficiency. Elbow pain or join deformity in the paretic limb. Pregnancy. Uncontrolled psychiatric disease. Aphasia or severe cognitive deficit. Inability to provide consent. Inability to attend the experimental sessions.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Active, subacute stroke<br>Repetitive peripheral electrical stimulation (RPES) + Motor Training. Active RPES will be administered for 2 hours. After active session of RPES, the patient will receive motor training. | Device: Repetitive peripheral nerve stimulation<br>* Active repetitive peripheral nerve stimulation will be applied to the median nerve of the affected forearm with surface electrodes. The stimulator will be set to deliver bursts of 10 Hz stimulation at 50% duty cycle (500 ms on and off). For active stimulation, intensities will be set at the highest intensity able to induce sensory paraesthesias without overt muscle contraction or pain, and adjusted if required.<br>|
| Sham Comparator: Sham, subacute stroke<br>Sham Comparator: Sham + Motor Training. Sham will be administered for 2 hours. After sham, the patient will receive motor training | Device: Sham Repetitive peripheral nerve stimulation<br>* Sham repetitive peripheral nerve stimulation will be applied to the median nerve of the affected forearm with surface electrodes. The stimulator will be set to deliver bursts of 10 Hz stimulation at 50% duty cycle (500 ms on and off). For sham stimulation, intensities will be set at 10mv - 15mv lower than de lowest intensity able to induce sensory paraesthesias, and adjusted if required.<br>|
| Active Comparator: Active, chronic stroke<br>Repetitive peripheral electrical stimulation (RPES) + Motor Training. Active RPES will be administered for 2 hours. After active session of RPES, the patient will receive motor training. | Device: Repetitive peripheral nerve stimulation<br>* Active repetitive peripheral nerve stimulation will be applied to the median nerve of the affected forearm with surface electrodes. The stimulator will be set to deliver bursts of 10 Hz stimulation at 50% duty cycle (500 ms on and off). For active stimulation, intensities will be set at the highest intensity able to induce sensory paraesthesias without overt muscle contraction or pain, and adjusted if required.<br>|
| Sham Comparator: Sham, chronic stroke<br>Sham Comparator: Sham + Motor Training. Sham will be administered for 2 hours. After sham, the patient will receive motor training | Device: Sham Repetitive peripheral nerve stimulation<br>* Sham repetitive peripheral nerve stimulation will be applied to the median nerve of the affected forearm with surface electrodes. The stimulator will be set to deliver bursts of 10 Hz stimulation at 50% duty cycle (500 ms on and off). For sham stimulation, intensities will be set at 10mv - 15mv lower than de lowest intensity able to induce sensory paraesthesias, and adjusted if required.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Jebsen-Taylor Test | Test of upper limb dexterity | Immediately after one session of intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in lateral pinch strength | Pinch strength measured with dynamometer | Immediately after one session of intervention | 
| Change in gamma-aminobutyric acid levels in primary motor cortex | Gamma-aminobutyric acid levels measured with magnetic resonance imaging spectroscopy | Immediately after one session of intervention | 
| Change in brain perfusion | Brain perfusion measured with magnetic resonance imaging - arterial spin labeling | Immediately after one session of intervention | 
| Change in grasp strength | Grasp strength measured with dynamometer | Immediately after one session of intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Rehabilitation, Neuromodulation, Peripheral stimulation, Motor function