Evidence of neuroplasticity with robotic hand exoskeleton study for post-stroke rehabilitation: a randomized controlled trial
Abstract Background: A novel electromechanical robotic-exoskeleton was designed in-house for the rehabilitation of wrist joint and Metacarpophalangeal (MCP) joint. Objective: The objective was to compare the rehabilitation effectiveness (clinical-scales and neurophysiological measures) of robotic-therapy training sessions with dose-matched \conventional therapy in patients with stroke.Methods: A pilot prospective parallel randomized controlled study at clinical-settings was designed with patients with stroke within 2 years of chronicity. Patients were randomly assigned to receive an intervention of 20 sessions of 45 minutes each, five days a week for four weeks, in Robotic-therapy Group (RG) (n=12) and conventional upper-limb rehabilitation in Control-Group (CG) (n=11). We hypothesized to evaluate the exoskeleton based therapy for the effects on the functionality of upper-limb and cortical-excitability in patients with stroke as compared to conventional rehabilitation. Clinical-scales– Modified Ashworth Scale, Active Range of Motion, Barthel Index, Brunnstrom Stage and Fugl-Meyer scale, and neurophysiological measures of cortical-excitability (using Transcranial Magnetic Stimulation) –Motor Evoked Potential and Resting Motor threshold, were acquired pre and post-therapy. No side effects were noticed in any of the patients. Results: Both RG and CG showed significant (p<0.05) improvement in all clinical motor-outcomes except Modified Ashworth Scale in CG. RG showed significantly (p<0.05) higher improvement over CG in Modified Ashworth Scale, Active Range of Motion, and Fugl-Meyer (FM) scale and FM Wrist-/Hand component. An increase in cortical-excitability in ipsilesional-hemisphere was found to be statistically significant (p<0.05) in RG over CG, as indexed by a decrease in Resting Motor Threshold and increase in the amplitude of Motor Evoked Potential. No significant changes were shown by the contralesional-hemisphere. Interhemispheric RMT-asymmetry evidenced significant (p<0.05) changes in RG over CG indicating increased cortical-excitability in ipsilesional-hemisphere along with interhemispheric changes. Conclusion: Robotic-exoskeleton training appears to be benificial for improving motor-outcomes and cortical-excitability in patients with stroke. Neurophysiological changes in RG could most likely be a consequence of plastic reorganization and use-dependent plasticity. Trial Registry Number: ISRCTN95291802