Stroke
Conditions
Keywords
Rehabilitation, Neuromodulation, Peripheral stimulation, Motor function
Brief summary
Upper limb paresis is the most common type of post-stroke neurological impairment and a major cause of functional disability. Repetitive peripheral sensory stimulation (RPSS) 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 RPSS on motor performance of the upper limb in the subacute and chronic phases of stroke, and to identify the mechanisms underlying this intervention.
Interventions
DEVICESuprathreshold repetitive peripheral sensory stimulation
Suprathreshold repetitive peripheral sensory 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 suprathreshold stimulation, intensities will be set at the highest intensity able to induce sensory paraesthesias without overt muscle contraction or pain, and adjusted if required.
DEVICESubthreshold repetitive sensory stimulation
Subthreshold repetitive sensory 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 subthreshold stimulation, intensities will be set at 10mv - 15mv lower than de lowest intensity able to induce sensory paraesthesias, and adjusted if required.
Sponsors
Fundação de Amparo à Pesquisa do Estado de São Paulo
Hospital Israelita Albert Einstein
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Masking description
An amendment for performance of a minimization procedure in order to enhance the probability of comparable characteristics between the groups was approved. The researcher responsible for minimization is not involved in data collection or analysis.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Jebsen-Taylor Test | Immediately after one session of intervention | Test of upper limb dexterity |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in lateral pinch strength | Immediately after one session of intervention | Pinch strength measured with dynamometer |
| Change in gamma-aminobutyric acid levels in primary motor cortex | Immediately after one session of intervention | Gamma-aminobutyric acid levels measured with magnetic resonance imaging spectroscopy |
| Change in brain perfusion | Immediately after one session of intervention | Brain perfusion measured with magnetic resonance imaging - arterial spin labeling |
| Change in grasp strength | Immediately after one session of intervention | Grasp strength measured with dynamometer |
Countries
Brazil
Outcome results
None listed