Distal upper limb targeted therapy with non-immersive virtual-reality based tasks in post-stroke rehabilitation

Virtual reality (VR) based assistive technology has been recently used as a potential approach in rehabilitation. The current objective is to evaluate the therapeutic potential of a customized VR-framework specific for distal upper limb rehabilitation in patients with chronic stroke, comparing it to dose-matched physiotherapy, while also exploring practice-dependent neuroplastic alterations in terms of cortical-excitability parameters. At clinical-settings, patients with chronic stroke were randomized to receive 20 sessions of therapy (45 min each), in VR-group (VRG; n = 9) and physiotherapy-group (PG; n = 9). Clinical outcomes and cortical-excitability measures i.e., motor evoked potential (MEP) amplitude and resting motor threshold (RMT) were acquired. Task-performance measures (trajectory smoothness, time to complete the task, and error) were computed for VRG. VRG demonstrated significant changes (p < 0.05) in Modified Ashworth Scale, Modified Barthel Index and wrist active range of motion as compared to PG from pre- to post-therapy. For VRG, significant enhancement in cortical excitability was observed with increased MEP amplitude and decreased RMT for ipsilesional hemisphere (p < 0.05). Intra-group changes in task-performance measures from session 1 to session 20 were significant for VRG (p < 0.05). VR-therapy demonstrated motor and neurophysiological improvements during the chronic recovery phase as compared to the physiotherapy. The exhibited cortical-excitability enhancement might result from the use-dependent plasticity induced by the distal upper-limb targeted VR-therapy. Clinical trial registered with ISRCTN registry https://doi.org/10.1186/ISRCTN17494358 ; Registration Number: ISRCTN17494358.