The Role of Trans-spinal Direct Current Stimulation (tsDCS) in Treating Patients With Hand Spasticity After Stroke

Phase 1

Completed

Conditions: Cerebrovascular Accident (CVA)
Hemiparesis
Muscle Spasticity
Spasticity as Sequela of Stroke
Upper Extremity Paralysis
Stroke

Brief Summary: The purpose of this study is to evaluate if 5 consecutive sessions of PathMaker anodal DoubleStim treatment, which combines non-invasive stimulation of the spinal cord (tsDCS- trans-spinal direct current stimulation) and of the median nerve at the peripheral wrist (pDCS-- peripheral direct current stimulation), can significantly reduce spasticity of the wrist and hand after stroke.

Recruitment & Eligibility

Inclusion Criteria

First single focal unilateral hemisphere lesion with diagnosis verified by brain imaging (MRI or CT scans) that occurred at least 6 months prior
Cognitive function sufficient to understand the experiments and follow instructions
A Modified Ashworth Scale score between 1-3 points for wrist flexor and extensor muscles
A minimum of 15 degrees wrist passive range of motion (ROM) for wrist flexion and extension from wrist neutral position

Exclusion Criteria

Focal brainstem or thalamic infarcts
Prior surgical treatments for spasticity of the upper limb
Ongoing use of central nervous system (CNS)-active medications
Ongoing use of psychoactive medications, such as stimulants, antidepressants, and anti-psychotic medications
Botox or phenol alcohol treatment within 12 weeks of enrollment
Pregnancy in women, as determined by self-report
History of spinal cord injury or weakness
Chronic pain
Peripheral neuropathy including insulin dependent diabetes as determined by case history
Presence of additional potential tsDCS risk factors:
- Damaged skin at the site of stimulation (i.e., skin with ingrown hairs, acne, razor nicks, wounds that have not healed recent scar tissue, broken skin, etc.)
- Presence of an electrically, magnetically or mechanically activated implant (including cardiac pacemaker), an intracerebral vascular clip, or any other electrically sensitive support system
- Highly conductive metal in any part of the body, including metal injury to the eye (jewelry must be removed during stimulation)
- Past history of seizures or unexplained spells of loss of consciousness during the previous 36 months

Arm && Interventions

Group	Intervention	Description
Sham Doublestim	sham Doublestim	Participants first received 5 daily, consecutive 20 min sessions of sham Doublestim (trans-spinal direct current stimulation + peripheral direct current stimulation). After a washout period of 1 week, they then received 5 daily, consecutive 20 min sessions of anodal Doublestim (trans-spinal direct current stimulation + peripheral direct current stimulation). For all participants, the sham condition preceded the anodal Doublestim condition.
Anodal Doublestim	anodal Doublestim	Participants first received 5 daily, consecutive 20 min sessions of sham Doublestim (trans-spinal direct current stimulation + peripheral direct current stimulation). After a washout period of 1 week, they then received 5 daily, consecutive 20 min sessions of anodal Doublestim (trans-spinal direct current stimulation + peripheral direct current stimulation). For all participants, the sham condition preceded the anodal Doublestim condition.

Primary Outcome Measures

Name	Time	Method
Mean Percent Change From Baseline in Area Under the Curve for Objectively Measured Spastic Catch Response of the Wrist Flexors at Fast Speed	baseline, final session at day 5, 1 week FU	Subjects' wrists were passively extended at fast speed by a stepper motor to induce a spastic catch response, and its resistance torque was calculated in Newton meters (Nm). Mean percent change from baseline in the area under the curve for the resistance torque were compared across two timepoints (final session at day 5 and 1 week follow-up) in two conditions (sham vs. anodal Doublestim)

Secondary Outcome Measures

Name	Time	Method
Mean Modified Tardieu Scale (MTS) Score	baseline, final session at day 5, 1 week FU	The Modified Tardieu Scale (MTS) quantifies muscle spasticity for each joint at slow and fast velocities on a 0-5 point scale. MTS scores at fast velocity were summed across 11 joints of the upper extremity (for a total of 0-55 points), with lower scores indicating improved spasticity. Mean summed MTS scores (out of 55 total points) were compared across two timepoints (final session at day 5 and 1 week FU) in two conditions (sham vs. anodal Doublestim).