Effect of Virtual Reality Gait Training on Participation in Survivors of Subacute Stroke: A Randomized Controlled Trial

De Rooij IJM, Van De Port IGL, Punt M, et al. Effect of Virtual Reality GAIT training on participation in survivors of subacute Stroke: a randomized controlled trial. Physical Therapy. 2021;101(5). doi:10.1093/ptj/pzab051

Link to Original Article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8122468/

Key Points

1. The study aimed to examine the effect of virtual reality gait training (VRT) compared to non-virtual reality gait training (non-VRT) on participation in community-living individuals after stroke.

2. The study involved a randomized controlled trial with two parallel groups, with participants assigned to either the VRT group or non-VRT group.

3. Both training interventions consisted of 12 30-minute sessions over a period of 6 weeks.

4. The primary outcome was participation measured with the restrictions subscale of the Utrecht Scale for Evaluation of Rehabilitation-Participation (USER-P) at 3 months post-intervention.

5. The results showed no significant differences between the VRT and non-VRT groups for the USER-P restrictions subscale or secondary outcome measures.

6. Participants' experiences with VRT were positive, and no serious adverse events were related to the interventions.

Introduction

The research paper discusses the effectiveness of Virtual Reality Gait Training (VRT) for people after a stroke in improving participation in community-living. Previous studies have shown that a considerable number of stroke survivors still face difficulties with walking in the community and performing daily activities. These difficulties can limit their participation in social, work, and household activities. Therefore, improving walking ability is a primary goal in stroke rehabilitation.

Virtual reality (VR) is increasingly being used in stroke rehabilitation to improve balance and walking function. VR training provides realistic environments where individuals can interact with objects and events in real-time. It allows for challenges such as adapting walking to unexpected situations and performing dual tasks. VR training can be adjusted to each patient's abilities and provides real-time feedback for motor recovery and enhanced motivation.

While previous studies have shown favorable effects of VR systems on balance and walking function, little evidence is available regarding follow-up assessments and outcomes related to activities of daily living and participation. Therefore, the primary aim of this study was to examine the effect of VR gait training on participation in community-living for stroke survivors between 2 weeks and 6 months post-stroke. Secondary outcomes, including subjective physical functioning, balance and walking ability, and walking activity, were also investigated. Additionally, the study aimed to explore the participants' experiences with VRT and how it influenced their walking ability and participation.

The hypothesis of the study was that treadmill-based VRT is a safe training intervention superior to non-VRT interventions, such as conventional treadmill training and functional gait exercises.

Methods

Study Design and Participants

This research study was an assessor-blinded, randomized controlled trial conducted to investigate the effectiveness of Virtual Reality Gait Training (VRT) on participation in people after a stroke. The study, called ViRTAS (Virtual Reality Training After Stroke), had a study protocol that was previously published and no changes were made to the study design or eligibility criteria throughout the study.

The participants were recruited primarily from a rehabilitation center, as well as from the neurology department of a local hospital, physical therapy practices, and general practices in the area. To be included in the study, potential participants had to meet certain criteria, including being diagnosed with a stroke according to the World Health Organization definition, having had a stroke within 2 weeks to 6 months, being able to walk without physical assistance for balance and coordination, experiencing self-perceived walking constraints in daily life, living in the community, and being between the ages of 18 to 80 years. Exclusion criteria included insufficient cognitive skills or comprehension of the Dutch language, severe visual impairments, severe forms of ataxia, uncontrolled epileptic seizures, orthopedic disorders, or other comorbidities that limited walking ability. All participants provided written informed consent.

In summary, this study used a randomized controlled trial design to investigate the effectiveness of VRT on participation in stroke survivors. The participants were recruited from various sources and had to meet specific inclusion criteria. The study protocol remained unchanged throughout, and all participants provided informed consent.

Procedures

The participants in the study were randomly assigned to either the Virtual Reality Gait Training (VRT) group or the non-VRT group. The randomization process was carried out by an independent expert who was not involved in the recruitment, intervention, or assessments. Sealed and opaque envelopes were used for the randomization process. Both groups received a training intervention consisting of two 30-minute sessions per week for six weeks, amounting to a total of 12 sessions. The assessments were conducted at three time points: baseline (T0), postintervention (T1, 6 weeks), and follow-up (T2, 3 months postintervention). The researcher who performed the assessments was blinded to the group allocation. However, due to the nature of the intervention, participants and intervention therapists could not be blinded to group allocation. The training sessions and assessments took place at the Revant Rehabilitation Centres in Breda, the Netherlands. Any adverse events that occurred during the study were recorded, and serious adverse events were reported to the medical ethics review committee.

Intervention Group

The intervention group in this study received Virtual Reality Gait Training (VRT) using the Gait Real-time Analysis Interactive Lab (GRAIL). The GRAIL combines an instrumented dual-belt treadmill with a motion-capture system and a 180° semi-cylindrical screen for 3-dimensional environments. Participants wore a harness for safety but without weight support. The VRT included various rehabilitative applications with specific goals such as reactive balance, maneuverability, and dual tasks. The difficulty level could be adjusted within the applications by modifying training options such as duration, treadmill speed, pitch and sway, belt acceleration or deceleration, simultaneous tasks, environmental constraints (obstacles), and real-time feedback. Specialized therapists trained in using the GRAIL conducted the VRT sessions. The therapists selected the applications for each training session based on therapeutic goals and could easily adapt the difficulty level according to individual abilities of the participants.

Comparison Group

The non-VRT intervention in this study consisted of a combination of two commonly used interventions to improve walking ability in individuals after a stroke. The first intervention was conventional treadmill training, lasting 10-15 minutes, in which the duration, speed, and/or incline of the treadmill were progressively increased while support from handrails was decreased. The second intervention was functional gait exercises, lasting 15 minutes, which included six directional exercises based on those used in the FIT-Stroke trial. These exercises included stepping up and down a step, walking and picking up objects from the ground, walking on non-level surfaces, walking in a slalom pattern, stepping in hoops, and stepping over a stick fixed between two pylons. The therapist decided which exercises were conducted during each training session, and individualization was achieved by adapting the number of repetitions, distance, height, variation, and the incorporation of dual tasks. This non-VRT intervention served as the comparison group in the study, and its effectiveness was compared to that of Virtual Reality Gait Training (VRT) in improving walking ability and participation in community-living for stroke survivors.

Outcome Measures

Primary Outcome

The primary outcome was measured using the restrictions subscale of the Utrecht Scale for Evlatuion of Rehabilitation-Participation (USER-P). The researches followed the participants up to 3 months postintervention. The restrictions subscale of the USER-P consists of 11 questions that asssess the partipation restrictions in the daily life. The participants answer using a numerical scale of 0 to 100 with 100 indicating no restrictions and 0 indicating full restrictions with ADLs.

Secondary Outcomes

The study included a number of secondary outcome measures to assess the effectiveness of Virtual Reality Gait Training (VRT) for people after a stroke in improving participation in community-living. These measures included the frequency and satisfaction subscales of the USER-P questionnaire, questionnaires on subjective physical functioning, fatigue, anxiety and depression, falls efficacy, and quality of life. Performance tests were also conducted to measure functional mobility, walking ability, and dynamic balance. Daily-life walking activity was assessed using a triaxial accelerometer over a period of five consecutive days.

The Mini-BESTest, a test that measures four underlying systems for balance control, was added to assess dynamic balance. Walking activity data from the accelerometer was analyzed using a stroke-specific algorithm in Matlab, and values such as total number of steps, total duration of walking activity, and step frequency were calculated. Participants had to wear the accelerometer for at least 3 days and walk for at least 5 minutes per day to be included in the analysis.

In addition, semi-structured interviews were conducted to explore participants' experiences with VRT. The interviews asked about advantages, disadvantages, and perceptions of how the VRT intervention influenced walking ability and participation. The interviews were transcribed and analyzed thematically using NVivo 12.

Overall, the study incorporated a range of outcome measures, including questionnaires, performance tests, accelerometer data, and qualitative interviews, to assess the impact of VRT on walking ability and participation for individuals after a stroke.

Data Analysis

The research study aimed to investigate the effectiveness of Virtual Reality Gait Training (VRT) for individuals after a stroke in improving their participation in community-living. The study obtained approval from the medical ethics review committee to recruit a sample size of 56 participants, which was revised based on reviewers' feedback. The revised calculation determined that 50 participants (25 per group) would be needed to detect a mean difference of 15% on the USER-P restrictions subscale. The analysis took into account a potential dropout rate of 10% to 20%.

The normality of the continuous outcome measures was visually checked, and log-transformation was applied to right-skewed variables involving time. The analysis followed a modified intention-to-treat principle, including all participants who attended at least one follow-up measurement. An analysis of covariance linear mixed-effects model was used to assess the effectiveness of VRT on the primary outcome measure. The model incorporated baseline USER-P restrictions, time, group assignment (VRT or non-VRT), and the interaction between time and group as fixed factors, with a random intercept per individual.

Secondary outcome variables were analyzed using similar mixed-effects models, with correction for baseline scores. Two sensitivity analyses were conducted for the primary outcome, including additional adjustment for the interaction between baseline USER-P restrictions and time, as well as adjusting for time since the stroke. Additionally, a per-protocol analysis was performed, including data only from participants who attended at least 75% of the training sessions.

All analyses were conducted using SPSS version 25, and results were considered significant if P values were less than .05.

Results

Between April 19, 2017, and July 26, 2019, a total of 55 participants were recruited for the study, with 28 assigned to the Virtual Reality Gait Training (VRT) group and 27 to the non-VRT group. Three participants in the non-VRT group were excluded, and a modified intent-to-treat analysis was conducted on 52 participants.

Baseline characteristics of the VRT and non-VRT groups were similar, except for the time since stroke, which was higher in the VRT group. Both groups received additional outpatient rehabilitation or therapy during the intervention period. The amount of exertion during training sessions did not significantly differ between the groups.

No serious adverse events related to the study interventions were reported. Adverse events during VRT sessions included near falls, dizziness, fatigue, and muscle stiffness or pain in the legs. Adverse events during non-VRT sessions included near falls, headache, increased clonus in the foot, breathing difficulty, dizziness, fatigue, and pain in the legs or back. Some adverse events resulted in more rest breaks or premature session termination, but none led to intervention discontinuation.

Training Characteristics and Patients' Experiences

The Training Characteristics and Patients' Experiences section of the research study on the effectiveness of Virtual Reality Gait Training (VRT) for people after a stroke revealed several key findings.

The results of 16 semi-structured interviews with participants showed that VRT was perceived as enjoyable, challenging, and intensive. Participants mentioned advantages such as the safe training environment, opportunities to train dual tasks, reaction time, obstacle avoidance, and reactive balance. They also appreciated the variation in exercises, the game elements, and the high intensity of the training. However, there were some disadvantages noted, including awareness of the safety harness, lack of real objects to step over, flash effects on the screen, and technical issues with the VR system.

The majority of participants reported that VRT had a positive impact on their walking ability. They experienced improvements in balance ability, the ability to perform dual tasks, take steps and walk on irregular surfaces, reaction time, and walking speed. Some participants also mentioned that walking felt easier and more automatic after the VRT intervention.

In terms of daily life participation, participants reported improved confidence during walking, the ability to cope with busy environments and stimuli, increased walking endurance, and reduced difficulty with self-care and household chores. Despite receiving other therapies, participants believed that VRT played a significant role in their overall improvements.

These findings suggest that VRT has a beneficial effect on walking ability and daily life participation for people after a stroke. The enjoyable and challenging nature of VRT, along with its ability to target specific aspects of walking, make it a promising intervention for stroke survivors.

Efficacy Outcomes

The study examined the effectiveness of Virtual Reality Gait Training (VRT) in improving participation in community-living for people after a stroke. The researchers measured outcomes at baseline, postintervention, and follow-up for both the VRT and non-VRT groups. Results showed that all participants, regardless of group allocation, experienced significant improvements in participation and dynamic balance over time. There was no significant difference in the USER-P restriction score between the VRT and non-VRT groups over time. However, the VRT group showed a slightly higher improvement in the USER-P restriction score compared to the non-VRT group, although this difference was not statistically significant. Sensitivity analyses and perprotocol analysis did not yield substantial differences in results. Secondary outcome measures did not reveal any statistically significant differences between the VRT and non-VRT groups over time. Overall, the study suggests that VRT may have a positive impact on walking ability and participation for people after a stroke, but further research is needed to determine the extent of its effectiveness.

Discussion

The research study explored the effectiveness of Virtual Reality Gait Training (VRT) in improving participation in community-living for individuals after a stroke. The study found that VRT was a safe and well-received intervention. However, there were no statistically significant differences between the VRT group and the non-VRT group in terms of quantitative outcome measures, including participation, subjective physical functioning, balance and walking ability, walking activity, and falls efficacy. The study also found that participation improved in both the VRT and non-VRT groups, with the VRT group showing a greater improvement than the non-VRT group. Spontaneous neurologic recovery and the small contrast between the VRT and non-VRT interventions were identified as possible explanations for the lack of significant between-group differences. Additionally, not personalizing the VRT intervention optimally and not measuring underlying walking impairments and patient-specific rehabilitation goals may have affected the results. The participants in the study reported positive experiences with VRT, highlighting its effectiveness in promoting important principles of motor learning such as high-intensity training with task variation and real-time feedback. They also mentioned improvements in cognitive function, confidence during walking, and movement automaticity as a result of VRT. However, the study had limitations, including a small sample size and the therapists' knowledge of both interventions. Overall, while VRT was well-received and showed potential benefits, further research with larger sample sizes and improved personalization is needed to establish its effectiveness in improving participation after a stroke.

Conclusion

The research study aimed to investigate the effectiveness of Virtual Reality Gait Training (VRT) for improving participation in community-living for people after a stroke. The study found that the effect of VRT was not statistically different from non-VRT in terms of participation. However, both interventions were shown to contribute to improvement in participation and can be considered in stroke rehabilitation based on individual rehabilitation goals or patient preference. Although not statistically significant, participation showed greater improvement in the VRT group. The participants who underwent VRT rated it positively and it was well-tolerated and clinically practicable, with good adherence and limited adverse events. These findings suggest that treadmill-based VRT can be a valuable addition to stroke rehabilitation. However, future studies should further investigate the cost-effectiveness and additional benefits of VRT for specific rehabilitation goals. Overall, VRT shows promise as a beneficial intervention for people after a stroke, but further research is needed to fully understand its potential impact and value.

Opportunities for Future Research

1. Investigate the long-term effects of virtual reality gait training (VRT) on participation in community-living individuals after stroke.

2. Compare the effects of different durations or intensities of VRT on participation outcomes in stroke survivors.

3. Assess the impact of VRT on specific aspects of walking function, such as reactive balance and dual-task performance.

4. Explore the potential benefits of combining VRT with other rehabilitation interventions, such as task-specific training or constraint-induced movement therapy.

5. Investigate the cost-effectiveness of VRT compared to non-VRT interventions for improving participation in stroke survivors.

6. Examine the effects of VRT on participation outcomes in different subgroups of stroke survivors, such as those with different levels of walking ability or cognitive impairments.