NCT04165616 · Northwestern University
Motor rECovery witH eArly imagiNg In STroke
(MECHANIST)
What this study is about
This study will contribute to the field of stroke rehabilitation research by expanding the investigator's understanding of the neural mechanisms responsible for the development and expression of abnormal flexion synergy, a primary movement impairment due to stroke.
View original scientific description
This study will contribute to the field of stroke rehabilitation research by expanding the investigator's understanding of the neural mechanisms responsible for the development and expression of abnormal flexion synergy, a primary movement impairment due to stroke. The study will longitudinally evaluate motor tract morphology and motor impairment/function in an attempt to develop early neuroimaging-based predictors of the development of flexion synergy and its impact on reaching and hand recovery (6 month). The study will utilize quantitative motor testing (kinematics and kinetics) to measure motor impairment and reaching and hand function. Both neuroimaging and quantitative motor testing will be conducted within 96 hours-, 2 weeks-, 3 months-, and 6 months-post stroke. The knowledge gained by this study will provide crucial structural and functional neuroimaging evidence that demonstrates the timeline of progressive ipsi- and contralesional motor pathway (including bulbospinal pathways) changes and the associated development of flexion synergy that grossly impacts reaching and hand function in individuals with moderate to severe stroke.
Primary outcome measures
Change in fractional anisotropy
Time frame: Change in fractional anisotropy will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Fractional anisotropy is a quantitative measure of fiber density, axonal diameter, and myelination in the corticofugal, corticoreticulospinal, and corticorubrospinal tracts derived from the diffusion tensor imaging dataset.
Change in complexity
Time frame: Change in complexity will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Complexity (alpha) is an index of the non-Gaussian diffusion dynamics within the corticofugal, corticoreticulospinal, and corticorubrospinal tracts derived from the diffusion tensor imaging dataset.
Change in mean diffusivity
Time frame: Change in mean diffusivity will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Mean diffusivity is a measure of neural tract integrity quantifying the rotationally invariant magnitude of water diffusion within neural tissue defined by the 3-dimensional diffusion tensor.
Change in radial diffusivity
Time frame: Change in radial diffusivity will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Radial diffusivity is a measure of neural membrane integrity quantifying the average of the two small-axis values of water diffusion within neural tissue defined by the 3-dimensional diffusion tensor.
Change in axial diffusivity
Time frame: Change in axial diffusivity will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Axial diffusivity is a measure of neural tract direction quantifying the long-axis value of water diffusion within neural tissue defined by the 3-dimensional diffusion tensor.
Change in maximum reaching distance
Time frame: Change in maximum reaching distance will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Quantitative evaluation of reaching accounting for the expression of both flexion synergy and weakness by calculating distance from reaching kinematics data during ballistic outward reaches against various abduction loads.
Change in maximum hand aperture
Time frame: Change in maximum hand aperture will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Quantitative evaluation of hand opening accounting for the expression of both flexion synergy and weakness by calculating the area of a pentagon formed by the finger tips from hand kinematics data obtained at various abduction loads.
Change in maximum grasp force
Time frame: Change in maximum grasp force will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
Quantitative evaluation of hand closing accounting for the expression of both flexion synergy and weakness by calculating the mean surface grasp force of the hand at various abduction loads.
Predictive capacity of diffusor tensor imaging (DTI) for 6-month reaching and hand performance
Time frame: Changes in structural morphology from 48 hours to 2-weeks post-stroke will be evaluated as early predictors for the 6-month reaching and hand performance outcomes including ROC curve analysis.
Changes in structural morphology measured acutely will be evaluated as early predictors for chronic reaching and hand performance. Receiver operating characteristic (ROC) curve analysis will be used to evaluate the discrimination potential of each acute imaging measure in predicting chronic moderate versus severe motor impairment for each of the reaching and hand performance measures.
Relationship between DTI and quantitative motor testing
Time frame: Relationships between metrics will be modeled over 4 time points (48-96 hours-, 2 weeks-, 3 months-, and 6 months post-stroke).
The relationship between each structural morphology metric and each quantitative motor testing metric will be evaluated.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Stroke within the middle cerebral artery distribution based on brain MRI done within 48 hours of admission
- 18 to 85 years old
- Isolated motor deficits (hemiparesis) without significant aphasia, visual disturbances, or neglect based on the following scores on the NIH Stroke Scale: 1a (level of consciousness) = 0- Alert; keenly responsive. 1b (LOC questions) = 0- Asked month and age; Answers both correctly. 1c (LOC commands) = 0- Asked to open/close eyes, grasp/release hand; Performs both correctly. 2 (Best Gaze) = 0- Horizontal eye movements; Normal. 5 (Motor Arm) = 1, 2, 3, or 4- Arm placed at 90 (sitting) or 45 (supine), Drift, Some effort, No effort against gravity, or No movement. 7 (Limb Ataxia) = 0- Finger-nose-finger or heel-shin test; Absent. 8 (Sensory) = 0 or 1- Pin prick; Normal or Mild-to-moderate sensory loss. 9 (Best Language) = 0 or 1- Describe picture; No or Mild-to-moderate Aphasia. 11 (Extinction and Inattention) = 0 or 1- No abnormality or Inattention to one modality.
Exclusion criteria
- Premorbid disability or sensorimotor impairment
- Comorbidity medically contraindicating the administration of subsequent MRI scanning and motor assessments
- Pain or hypersensitivity limiting motor assessment
- Limb edema limiting motor assessment
Where
- Chicago, Illinois
Collaborators
National Institute of Neurological Disorders and Stroke (NINDS), Shirley Ryan AbilityLab
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Data: ClinicalTrials.gov · synced Sep 5, 2025 · Source of record for eligibility and locations