The Association Between Reorganization of Bilateral M1 Topography and Function in Response to Early Intensive Hand Focused Upper Limb Rehabilitation Following Stroke Is Dependent on Ipsilesional Corticospinal Tract Integrity

Abstract

Transcranial magnetic stimulation (TMS) induced motor evoked potentials (MEPs) are an established proxy of corticospinal excitability. As a binary measure, the presence (MEP+) or absence (MEP-) of ipsilesional hemisphere MEPs early following stroke is a robust indicator of long-term recovery, however this measure does not provide information about spatial cortical reorganization. MEPs have been systematically acquired over the sensorimotor cortex to “map” motor topography. In this investigation we compared the degree to which functional improvements resulting from early (<3 months post-stroke) intensive hand focused upper limb rehabilitation correlate with changes in motor topography between MEP+ and MEP- individuals. Following informed consent, 17 individuals (4 Female, 60.3 ± 9.4 years, 24.6 ± 24.01 days post first time stroke) received 8 one hour-sessions of training with virtual reality (VR)/Robotic simulations. Clinical tests [Box and Blocks Test (BBT), Wolf Motor Function Test (WMFT), Upper Extremity Fugl-Meyer (UEFMA)], kinematic and kinetic assessments [finger Active Range of Motion (finger AROM), Maximum Pinch Force (MPF)], and bilateral TMS mapping of 5 hand muscles were performed prior to (PRE), directly following (POST), and 1 month following (1M) training. Participants were divided into two groups (MEP+, MEP-) based on whether an MEP was present in the affected first dorsal interosseous (FDI) at any time point. MEP+ individuals improved significantly more than MEP- individuals from PRE to 1M on the WMFT, BBT, and finger AROM scores. Ipsilesional hemisphere FDI area increased significantly with time in the MEP+ group. FDI area of the contralesional hemisphere was not significantly different across time points or groups. In the MEP+ group, significant correlations were observed between PRE-1M changes in ipsilesional FDI area and WMFT, BBT, and finger AROM, and contralesional FDI area and UEFMA and MPF. In the MEP- group, no significant correlations were found between changes in contralesional FDI area and functional outcomes. We report preliminary evidence in a small sample that patterns of recovery and the association of recovery to bilateral changes in motor topography may depend on integrity of the ipsilesional cortical spinal tract as assessed by the presence of TMS evoked MEPs.

Diagnostic capabilities of transcranial magnetic stimulation to predict motor recovery after a stroke

“…[13] для исследования были предложены уже 2 мышцы -1-я межкостная мышца и лучевой разгибатель запястья, а наличие ВМО определялось как возможность вызвать ВМО по крайней мере в одной из них [13]. В других исследованиях использовалась только одна мышца, при этом выбор мышцы между исследованиями варьировался [19][20][21]. Опубликованы результаты работы, в которой наличие ВМО в проксимальной мышце (двуглавой мышце плеча) и дистальной мышце (1-я межкостная мышца кисти) обладало разной прогностической способностью в отношении восстановления кисти и предплечья [22].…”

Evidence of Neuroplasticity: A Robotic Hand Exoskeleton Study for Post-Stroke Rehabilitation

“…is particularly impervious to therapy or rehabilitation pertaining to the complexity of motor-control needed for distal-joints (4). Conventional rehabilitation-therapy is time taking, labour-intensive and subjective, which with high clinical-load and absence of skilled resources gets di cult for the present medical and healthcare-system to provide appropriate or effective rehabilitation services (5).…”

Evidence of Neuroplasticity With Robotic Hand Exoskeleton Study for Post-Stroke Rehabilitation: A Randomized Controlled Trial

“…The ability to actively initiate extension movements at wrist and ngers against exor-hypertonia is one of the key indicators of motor recovery (2), (3). Regaining hand-function and Activities of daily-living (ADL) is particularly impervious to therapy or rehabilitation pertaining to the complexity of motor-control needed for distal-joints (4). Conventional rehabilitationtherapy is time taking, labour-intensive and subjective, which with high clinical-load and absence of skilled resources gets di cult for the present medical and healthcare-system to provide appropriate or effective rehabilitation services (5).…”