Effects of tDCS on Quadriceps Strength After Stroke

Study Overview
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Brief Summary
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Previous studies show that one session of tDCS allow to improve muscle strength in hemiparetic patients in anodal condition. We test a new electrods configuration : a anodale stimulation opposite to the cortical representation area of the injured hemisphere and a simultaneous stimulation opposite to the homonyme the cortical representation area of the healthy hemisphere. This approach seems to be the best relevant electrods configuration in order to restore the inter-hemispheric balance. We hypothesis that one session of tDCS with this electrods configuration allow to improve paretic quadriceps strength in hemiparetic patients after stroke.

Official Title
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a Controlled, Randomized Study Evaluating the Immediate Effect of One tDCS Session on Quadriceps Strength in Hemiparetic Patients.

Conditions
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Stroke

Intervention / Treatment
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* Device: transcranial Direct current stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: written consent hemiparetic patient after stroke in chronic phase (> 6 months) capacity to walk with or without technical assistance following rehabilitation program for lower limbs Exclusion Criteria: patient with bilateral brain lesion, cerebellar syndrom, and apraxia and/or aphasia previous orthopedic surgery in paretic lower limb (<6 moths) usual tDCS contraindications pregnant woman

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: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: hemiplegic patient<br>anodal transcranial direct current stimulation | Device: transcranial Direct current stimulation<br> <br> |
| Sham Comparator: patient control<br>Sham transcranial direct current stimulation | Device: transcranial Direct current stimulation<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| maximum voluntary isometric strength of knee extensors | The maximum voluntary isometric strength of paretic knee extensors will be evaluated with a isokinetic dynamometer, which measure peak torque. | 2 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resistive peak torque during passive knee flexion |  | 2h | 
| Angle related to the resistive peak torque generation of the knee extensors |  | 2h | 
| Amplitude of the interpolation twitch |  | 2h | 
| EMG activation of the knee flexors and extensors during the strength evaluations (active and passive) |  | 2h | 
| Functional evaluation of the gait performance and balance |  | 2h | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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tDCS, Stroke, Force, Spasticity, Gait, EMG, Isokinetic