The effects of virtual reality training in stroke and Parkinson's disease rehabilitation: a systematic review and a perspective on usability

Background Virtual Reality (VR) training is emerging in the neurorehabilitation field. Technological advancement is often faster than clinical implementation. Previous reviews stressed the study design and methodological weaknesses of research in the field of VR for neurorehabilitation. Clinically relevant conclusions on implementation in particular patient groups are needed. The aim was to update the existing knowledge with the recent evidence on the effects of VR training on functional ability of patients with stroke and Parkinson's Disease (PD). Secondary objective was to analyze the aspects of usability of VR intervention in these populations. Methods Systematic literature search (via PubMed, CENTRAL) was conducted from inception to February 29, 2020 to identify suitable articles for two population subcategories. Randomized controlled trials published from 2016 to 2020, investigating the effectiveness of VR on a variety of outcomes contributing to the functional independence were included. Critical Appraisal Skills Programme (CASP) checklist was used for a methodological quality assessment of the primary studies. Given the heterogeneity in types of VR intervention and outcomes, a descriptive synthesis was conducted. Results A total of 18 randomized controlled trials were included (10 in stroke subcategory, 8 in PD). CASP grading ranged 9-11, suggesting high methodological quality. All studies concluded that overall VR might be as effective as the conventional training, but more motivating. In some studies, VR was found to have a greater effect, taking the high response to treatment and satisfaction into account. Conclusions VR training is suggested as an effective intervention to improve the functional ability in stroke and PD patients. Addition of VR into a rehabilitation program might facilitate patient's motivation, participation and improvement, as this method was generally well accepted, and the results of trials were promising. The consideration of disorder-specific aspects should take place during the decision-making of VR implementation.