Improvement in balance using a virtual reality-based stepping exercise: a randomized controlled trial involving individuals with chronic stroke

Virtual reality for stroke rehabilitation

BACKGROUND

Virtual reality and interactive video gaming have emerged as recent treatment approaches in stroke rehabilitation with commercial gaming consoles in particular, being rapidly adopted in clinical settings. This is an update of a Cochrane Review published first in 2011 and then again in 2015.

OBJECTIVES

Primary objective: to determine the efficacy of virtual reality compared with an alternative intervention or no intervention on upper limb function and activity.Secondary objectives: to determine the efficacy of virtual reality compared with an alternative intervention or no intervention on: gait and balance, global motor function, cognitive function, activity limitation, participation restriction, quality of life, and adverse events.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (April 2017), CENTRAL, MEDLINE, Embase, and seven additional databases. We also searched trials registries and reference lists.

SELECTION CRITERIA

Randomised and quasi-randomised trials of virtual reality ("an advanced form of human-computer interface that allows the user to 'interact' with and become 'immersed' in a computer-generated environment in a naturalistic fashion") in adults after stroke. The primary outcome of interest was upper limb function and activity. Secondary outcomes included gait and balance and global motor function.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials based on pre-defined inclusion criteria, extracted data, and assessed risk of bias. A third review author moderated disagreements when required. The review authors contacted investigators to obtain missing information.

MAIN RESULTS

We included 72 trials that involved 2470 participants. This review includes 35 new studies in addition to the studies included in the previous version of this review. Study sample sizes were generally small and interventions varied in terms of both the goals of treatment and the virtual reality devices used. The risk of bias present in many studies was unclear due to poor reporting. Thus, while there are a large number of randomised controlled trials, the evidence remains mostly low quality when rated using the GRADE system. Control groups usually received no intervention or therapy based on a standard-care approach.

PRIMARY OUTCOME

results were not statistically significant for upper limb function (standardised mean difference (SMD) 0.07, 95% confidence intervals (CI) -0.05 to 0.20, 22 studies, 1038 participants, low-quality evidence) when comparing virtual reality to conventional therapy. However, when virtual reality was used in addition to usual care (providing a higher dose of therapy for those in the intervention group) there was a statistically significant difference between groups (SMD 0.49, 0.21 to 0.77, 10 studies, 210 participants, low-quality evidence).

SECONDARY OUTCOMES

when compared to conventional therapy approaches there were no statistically significant effects for gait speed or balance. Results were statistically significant for the activities of daily living (ADL) outcome (SMD 0.25, 95% CI 0.06 to 0.43, 10 studies, 466 participants, moderate-quality evidence); however, we were unable to pool results for cognitive function, participation restriction, or quality of life. Twenty-three studies reported that they monitored for adverse events; across these studies there were few adverse events and those reported were relatively mild.

AUTHORS' CONCLUSIONS

We found evidence that the use of virtual reality and interactive video gaming was not more beneficial than conventional therapy approaches in improving upper limb function. Virtual reality may be beneficial in improving upper limb function and activities of daily living function when used as an adjunct to usual care (to increase overall therapy time). There was insufficient evidence to reach conclusions about the effect of virtual reality and interactive video gaming on gait speed, balance, participation, or quality of life. This review found that time since onset of stroke, severity of impairment, and the type of device (commercial or customised) were not strong influencers of outcome. There was a trend suggesting that higher dose (more than 15 hours of total intervention) was preferable as were customised virtual reality programs; however, these findings were not statistically significant.

Does body shadow improve the efficacy of virtual reality-based training with BTS NIRVANA?: A pilot study

BACKGROUND

Aim of the present study was to evaluate whether the presence of body shadows during virtual reality (VR) training with BTS NIRVANA (BTs-N) may lead to a better functional recovery.

METHODS

We enrolled 20 poststroke rehabilitation inpatients, who underwent a neurocognitive-rehabilitative training consisting of 24 sessions (3 times a week for 8 weeks) of BTs-N. All the patients were randomized into 2 groups: semi-immersive virtual training with (S-IVTS group) or without (S-IVT group) body shadows. Each participant was evaluated before (T0) and immediately (T1) after the end of the training (Trial Registration Number: NCT03095560).

RESULTS

The S-IVTS group showed a greater improvement in visuo-constructive skills and sustained attention, as compared with the S-IVT group. The other measures showed nonsignificant within-group and between-group differences.

CONCLUSION

Our results showed that body shadow may represent a high-priority class of stimuli that act by "pushing" attention toward the body itself. Further studies are needed to clarify the role of body shadow in promoting the internal representation construction and thus self-recognition.

Effects of sling exercise on postural sway in post-stroke patients

[Purpose] To examine the effects of sling exercise on the balance of post-stroke patients. [Subjects and Methods] A total of 18 post-stroke patients (13 men; mean age, 55.3 years) were recruited, and randomly assigned them into sling exercise (n=10) and control exercise (n=8) groups. The Good Balance System was used for measurement of velocity (anteroposterior and mediolateral, mm/s), velocity moment (mm²/s) of the movement of the center of pressure, and distance (anteroposterior and mediolateral, mm) between the center of pressure and the center point. The changes in mediolateral velocity, anteroposterior velocity, and velocity moment were compared between two groups in addition to the comparison of distance between the center of pressure and the center point of postural sway. [Results] The sling exercise group showed more significant improvements in anteroposterior velocity, mediolateral velocity, velocity moment, anteroposterior distance, and mediolateral distance than the control exercise group. [Conclusion] Sling exercise improved post-stroke balance performance and could be used as a therapeutic strategy to improve post-stroke functional recovery.

Markerless motion capture systems as training device in neurological rehabilitation: a systematic review of their use, application, target population and efficacy

Background

Client-centred task-oriented training is important in neurological rehabilitation but is time consuming and costly in clinical practice. The use of technology, especially motion capture systems (MCS) which are low cost and easy to apply in clinical practice, may be used to support this kind of training, but knowledge and evidence of their use for training is scarce. The present review aims to investigate 1) which motion capture systems are used as training devices in neurological rehabilitation, 2) how they are applied, 3) in which target population, 4) what the content of the training and 5) efficacy of training with MCS is.

Methods

A computerised systematic literature review was conducted in four databases (PubMed, Cinahl, Cochrane Database and IEEE). The following MeSH terms and key words were used: Motion, Movement, Detection, Capture, Kinect, Rehabilitation, Nervous System Diseases, Multiple Sclerosis, Stroke, Spinal Cord, Parkinson Disease, Cerebral Palsy and Traumatic Brain Injury. The Van Tulder’s Quality assessment was used to score the methodological quality of the selected studies. The descriptive analysis is reported by MCS, target population, training parameters and training efficacy.

Results

Eighteen studies were selected (mean Van Tulder score = 8.06 ± 3.67). Based on methodological quality, six studies were selected for analysis of training efficacy. Most commonly used MCS was Microsoft Kinect, training was mostly conducted in upper limb stroke rehabilitation. Training programs varied in intensity, frequency and content. None of the studies reported an individualised training program based on client-centred approach.

Conclusion

Motion capture systems are training devices with potential in neurological rehabilitation to increase the motivation during training and may assist improvement on one or more International Classification of Functioning, Disability and Health (ICF) levels. Although client-centred task-oriented training is important in neurological rehabilitation, the client-centred approach was not included. Future technological developments should take up the challenge to combine MCS with the principles of a client-centred task-oriented approach and prove efficacy using randomised controlled trials with long-term follow-up.

Trial registration

Prospero registration number 42016035582.

Electronic supplementary material

The online version of this article (doi:10.1186/s12984-017-0270-x) contains supplementary material, which is available to authorized users.

Biofeedback improves performance in lower limb activities more than usual therapy in people following stroke: a systematic review

QUESTION

Is biofeedback during the practice of lower limb activities after stroke more effective than usual therapy in improving those activities, and are any benefits maintained beyond the intervention?

DESIGN

Systematic review with meta-analysis of randomised trials with a PEDro score > 4.

PARTICIPANTS

People who have had a stroke.

INTERVENTION

Biofeedback (any type delivered by any signal or sense) delivered concurrently during practice of sitting, standing up, standing or walking compared with the same amount of practice without biofeedback.

OUTCOME MEASURES

Measures of activity congruent with the activity trained.

RESULTS

Eighteen trials including 429 participants met the inclusion criteria. The quality of the included trials was moderately high, with a mean PEDro score of 6.2 out of 10. The pooled effect size was calculated as a standardised mean difference (SMD) because different outcome measures were used. Biofeedback improved performance of activities more than usual therapy (SMD 0.50, 95% CI 0.30 to 0.70).

CONCLUSION

Biofeedback is more effective than usual therapy in improving performance of activities. Further research is required to determine the long-term effect on learning. Given that many biofeedback machines are relatively inexpensive, biofeedback could be utilised widely in clinical practice. [Stanton R, Ada L, Dean CM, Preston E (2016) Biofeedback improves performance in lower limb activities more than usual therapy in people following stroke: a systematic review.Journal of Physiotherapy63: 11-16].

Effect of Virtual Reality on Postural and Balance Control in Patients with Stroke: A Systematic Literature Review

Objective. To critically evaluate the studies that were conducted over the past 10 years and to assess the impact of virtual reality on static and dynamic balance control in the stroke population. Method. A systematic review of randomized controlled trials published between January 2006 and December 2015 was conducted. Databases searched were PubMed, Scopus, and Web of Science. Studies must have involved adult patients with stroke during acute, subacute, or chronic phase. All included studies must have assessed the impact of virtual reality programme on either static or dynamic balance ability and compared it with a control group. The Physiotherapy Evidence Database (PEDro) scale was used to assess the methodological quality of the included studies. Results. Nine studies were included in this systematic review. The PEDro scores ranged from 4 to 9 points. All studies, except one, showed significant improvement in static or dynamic balance outcomes group. Conclusions. This review provided moderate evidence to support the fact that virtual reality training is an effective adjunct to standard rehabilitation programme to improve balance for patients with chronic stroke. The effect of VR training in balance recovery is less clear in patients with acute or subacute stroke. Further research is required to investigate the optimum training intensity and frequency to achieve the desired outcome.

Effect of Virtual Reality Training on Balance and Gait Ability in Patients With Stroke: Systematic Review and Meta-Analysis

BACKGROUND

Virtual reality (VR) training is considered to be a promising novel therapy for balance and gait recovery in patients with stroke.

PURPOSE

The aim of this study was to conduct a systematic literature review with meta-analysis to investigate whether balance or gait training using VR is more effective than conventional balance or gait training in patients with stroke.

DATA SOURCES

A literature search was carried out in the databases PubMed, Embase, MEDLINE, and Cochrane Library up to December 1, 2015.

STUDY SELECTION

Randomized controlled trials that compared the effect of balance or gait training with and without VR on balance and gait ability in patients with stroke were included.

DATA EXTRACTION AND SYNTHESIS

Twenty-one studies with a median PEDro score of 6.0 were included. The included studies demonstrated a significant greater effect of VR training on balance and gait recovery after stroke compared with conventional therapy as indicated with the most frequently used measures: gait speed, Berg Balance Scale, and Timed "Up & Go" Test. Virtual reality was more effective to train gait and balance than conventional training when VR interventions were added to conventional therapy and when time dose was matched.

LIMITATIONS

The presence of publication bias and diversity in included studies were limitations of the study.

CONCLUSIONS

The results suggest that VR training is more effective than balance or gait training without VR for improving balance or gait ability in patients with stroke. Future studies are recommended to investigate the effect of VR on participation level with an adequate follow-up period. Overall, a positive and promising effect of VR training on balance and gait ability is expected.

Balance evaluation techniques and physical therapy in post-stroke patients: A literature review

A stroke (cerebrovascular accident - CVA) is a significant social-economic issue. Approximately 15-30% of all patients develop life-long disability, 20% require over 3 months of specialized care in healthcare institutions, and the majority of the patients never recover the ability to maintain a proper vertical position. Such CVA sequelae as balance disturbances not only negatively affect patients' daily physical activity, but also result in social isolation. A number of standardized clinical scales, tests, and instrumental examination techniques have been proposed for evaluating not only post-CVA balance function, but also any changes in this function following various interventions. Even though scientific literature lists numerous methods and instruments for the improvement of balance after a CVA, not all of them are equally effective, and there have been rather controversial evaluations of some techniques. Nevertheless, the application of the majority of the techniques as complementary or alternative measures to traditional physical therapy (PT) frequently yields better results.

Effects of virtual reality for stroke individuals based on the International Classification of Functioning and Health: a systematic review

OBJECTIVE

This review determines the effects of virtual reality interventions for stroke subjects based on the International Classification of Functioning, Disability,and Health (ICF) framework. Virtual reality is a promising tool for therapy for stroke rehabilitation, but the effects of virtual reality interventions on post-stroke patients based on the specific ICF domains (Body Structures, Body Functions, Activity, and Participation) have not been investigated.

METHOD

A systematic review was conducted, including trials with adults with a clinical diagnosis of a chronic, subacute, or acute stroke. Eligible trials had to include studies with an intervention protocol and follow-up, with a focus on upper limbs and/or lower limbs and/or balance. The Physiotherapy Evidence Database (PEDro) was used to assess the methodological quality of randomized controlled trials. Each trial was separated according to methodological quality into a high-quality trial (PEDro ≥ 6) and a low-quality trial (PEDro ≤ 6). Only high-quality trials were analyzed specifically based on the outcome of these trials.

RESULTS

In total, 54 trials involving 1811 participants were included. Of the papers included and considered high quality, 14 trials evaluated areas of the Body Structures component, 20 trials of the Body Functions domain, 17 trials of the Activity component, and 8 trials of the Participation domain. In relation to ICF Part 2, four trials evaluated areas of the Personal Factors component and one trial evaluated domains of the Environmental Factors component.

DISCUSSION

The effects of virtual reality on stroke rehabilitation based on the ICF framework are positive in Body Function and Body Structure. However, the results in the domains Activity and Participation are inconclusive. More high-quality clinical trials are needed to confirm the effectiveness of virtual reality in the domains of Activity and Participation.

Feasibility of a walking virtual reality system for rehabilitation: objective and subjective parameters

BACKGROUND

Even though virtual reality (VR) is increasingly used in rehabilitation, the implementation of walking navigation in VR still poses a technological challenge for current motion tracking systems. Different metaphors simulate locomotion without involving real gait kinematics, which can affect presence, orientation, spatial memory and cognition, and even performance. All these factors can dissuade their use in rehabilitation. We hypothesize that a marker-based head tracking solution would allow walking in VR with high sense of presence and without causing sickness. The objectives of this study were to determine the accuracy, the jitter, and the lag of the tracking system and its elicited sickness and presence in comparison of a CAVE system.

METHODS

The accuracy and the jitter around the working area at three different heights and the lag of the head tracking system were analyzed. In addition, 47 healthy subjects completed a search task that involved navigation in the walking VR system and in the CAVE system. Navigation was enabled by natural locomotion in the walking VR system and through a specific device in the CAVE system. An HMD was used as display in the walking VR system. After interacting with each system, subjects rated their sickness in a seven-point scale and their presence in the Slater-Usoh-Steed Questionnaire and a modified version of the Presence Questionnaire.

RESULTS

Better performance was registered at higher heights, where accuracy was less than 0.6 cm and the jitter was about 6 mm. The lag of the system was 120 ms. Participants reported that both systems caused similar low levels of sickness (about 2.4 over 7). However, ratings showed that the walking VR system elicited higher sense of presence than the CAVE system in both the Slater-Usoh-Steed Questionnaire (17.6 ± 0.3 vs 14.6 ± 0.6 over 21, respectively) and the modified Presence Questionnaire (107.4 ± 2.0 vs 93.5 ± 3.2 over 147, respectively).

CONCLUSIONS

The marker-based solution provided accurate, robust, and fast head tracking to allow navigation in the VR system by walking without causing relevant sickness and promoting higher sense of presence than CAVE systems, thus enabling natural walking in full-scale environments, which can enhance the ecological validity of VR-based rehabilitation applications.

Effect of a mixed reality-based intervention on arm, hand, and finger function on chronic stroke

Background

Virtual and mixed reality systems have been suggested to promote motor recovery after stroke. Basing on the existing evidence on motor learning, we have developed a portable and low-cost mixed reality tabletop system that transforms a conventional table in a virtual environment for upper limb rehabilitation. The system allows intensive and customized training of a wide range of arm, hand, and finger movements and enables interaction with tangible objects, while providing audiovisual feedback of the participants’ performance in gamified tasks. This study evaluates the clinical effectiveness and the acceptance of an experimental intervention with the system in chronic stroke survivors.

Methods

Thirty individuals with stroke were included in a reversal (A-B-A) study. Phase A consisted of 30 sessions of conventional physical therapy. Phase B consisted of 30 training sessions with the experimental system. Both interventions involved flexion and extension of the elbow, wrist, and fingers, and grasping of different objects. Sessions were 45-min long and were administered three to five days a week. The body structures (Modified Ashworth Scale), functions (Motricity Index, Fugl-Meyer Assessment Scale), activities (Manual Function Test, Wolf Motor Function Test, Box and Blocks Test, Nine Hole Peg Test), and participation (Motor Activity Log) were assessed before and after each phase. Acceptance of the system was also assessed after phase B (System Usability Scale, Intrinsic Motivation Inventory).

Results

Significant improvement was detected after the intervention with the system in the activity, both in arm function measured by the Wolf Motor Function Test (p < 0.01) and finger dexterity measured by the Box and Blocks Test (p < 0.01) and the Nine Hole Peg Test (p < 0.01); and participation (p < 0.01), which was maintained to the end of the study. The experimental system was reported as highly usable, enjoyable, and motivating.

Conclusions

Our results support the clinical effectiveness of mixed reality interventions that satisfy the motor learning principles for upper limb rehabilitation in chronic stroke survivors. This characteristic, together with the low cost of the system, its portability, and its acceptance could promote the integration of these systems in the clinical practice as an alternative to more expensive systems, such as robotic instruments.

Electronic supplementary material

The online version of this article (doi:10.1186/s12984-016-0153-6) contains supplementary material, which is available to authorized users.

Gait adaptation to visual kinematic perturbations using a real-time closed-loop brain-computer interface to a virtual reality avatar

OBJECTIVE

The control of human bipedal locomotion is of great interest to the field of lower-body brain-computer interfaces (BCIs) for gait rehabilitation. While the feasibility of closed-loop BCI systems for the control of a lower body exoskeleton has been recently shown, multi-day closed-loop neural decoding of human gait in a BCI virtual reality (BCI-VR) environment has yet to be demonstrated. BCI-VR systems provide valuable alternatives for movement rehabilitation when wearable robots are not desirable due to medical conditions, cost, accessibility, usability, or patient preferences.

APPROACH

In this study, we propose a real-time closed-loop BCI that decodes lower limb joint angles from scalp electroencephalography (EEG) during treadmill walking to control a walking avatar in a virtual environment. Fluctuations in the amplitude of slow cortical potentials of EEG in the delta band (0.1-3 Hz) were used for prediction; thus, the EEG features correspond to time-domain amplitude modulated potentials in the delta band. Virtual kinematic perturbations resulting in asymmetric walking gait patterns of the avatar were also introduced to investigate gait adaptation using the closed-loop BCI-VR system over a period of eight days.

MAIN RESULTS

Our results demonstrate the feasibility of using a closed-loop BCI to learn to control a walking avatar under normal and altered visuomotor perturbations, which involved cortical adaptations. The average decoding accuracies (Pearson's r values) in real-time BCI across all subjects increased from (Hip: 0.18 ± 0.31; Knee: 0.23 ± 0.33; Ankle: 0.14 ± 0.22) on Day 1 to (Hip: 0.40 ± 0.24; Knee: 0.55 ± 0.20; Ankle: 0.29 ± 0.22) on Day 8.

SIGNIFICANCE

These findings have implications for the development of a real-time closed-loop EEG-based BCI-VR system for gait rehabilitation after stroke and for understanding cortical plasticity induced by a closed-loop BCI-VR system.

A Closed-loop Brain Computer Interface to a Virtual Reality Avatar: Gait Adaptation to Visual Kinematic Perturbations

The control of human bipedal locomotion is of great interest to the field of lower-body brain computer interfaces (BCIs) for rehabilitation of gait. While the feasibility of a closed-loop BCI system for the control of a lower body exoskeleton has been recently shown, multi-day closed-loop neural decoding of human gait in a virtual reality (BCI-VR) environment has yet to be demonstrated. In this study, we propose a real-time closed-loop BCI that decodes lower limb joint angles from scalp electroencephalography (EEG) during treadmill walking to control the walking movements of a virtual avatar. Moreover, virtual kinematic perturbations resulting in asymmetric walking gait patterns of the avatar were also introduced to investigate gait adaptation using the closed-loop BCI-VR system over a period of eight days. Our results demonstrate the feasibility of using a closed-loop BCI to learn to control a walking avatar under normal and altered visuomotor perturbations, which involved cortical adaptations. These findings have implications for the development of BCI-VR systems for gait rehabilitation after stroke and for understanding cortical plasticity induced by a closed-loop BCI system.

Effect of a virtual reality exercise program accompanied by cognitive tasks on the balance and gait of stroke patients

[Purpose] This study aimed to assess the effect of a virtual reality exercise program accompanied by cognitive tasks on the balance and gait of stroke patients. [Subjects] Twenty stroke patients were randomly assigned to two groups 10 to an experimental group that performed a virtual reality exercise program accompanied by cognitive tasks and 10 to a control group. The control group performed a proprioceptive neuromuscular facilitation exercise program. Balance was measured with the Berg Balance Scale. Gait was assessed using the Timed Up and Go Test. The paired t-test was used to compare groups before and after the experiment. The independent t-test was conducted to assess differences in the degree of change between the two groups before and after the experiment. [Results] Within-group comparison in the experimental group showed significant differences in the Berg Balance Scale and Timed Up and Go Test. In a comparison between groups, the differences in the Berg Balance Scale and Timed Up and Go Test in the experimental group appeared significant compared with the control group. [Conclusion] The results of the experiment indicate that a virtual reality exercise program accompanied by cognitive tasks has a positive effect on the balance and gait of stroke patients.

Virtual reality for improving balance in patients after stroke: A systematic review and meta-analysis

Objective:

To evaluate the effectiveness of virtual reality interventions for improving balance in people after stroke.

Design:

Systematic review and meta-analysis of randomized controlled trials.

Methods:

Studies were obtained by searching the following databases: MEDLINE, CINAHL, EMBASE, Web of Science and CENTRAL. Two reviewers assessed studies for inclusion, extracted data and assessed trial quality.

Results:

Sixteen studies involving 428 participants were included. People who received virtual reality interventions showed marked improvements in Berg Balance Scale (mean difference: 1.46, 95% confidence interval: 0.09–2.83, P<0.05, I²=0%) and Timed Up and Go Test (mean difference: –1.62, 95% confidence interval: –3.07– –0.16, P<0.05, I²=24%) compared with controls.

Conclusions:

This meta-analysis of randomized controlled trials supports the use of virtual reality to improve balance after stroke.

Rehabilitation that incorporates virtual reality is more effective than standard rehabilitation for improving walking speed, balance and mobility after stroke: a systematic review

QUESTION

In people after stroke, does virtual reality based rehabilitation (VRBR) improve walking speed, balance and mobility more than the same duration of standard rehabilitation? In people after stroke, does adding extra VRBR to standard rehabilitation improve the effects on gait, balance and mobility?

DESIGN

Systematic review with meta-analysis of randomised trials.

PARTICIPANTS

Adults with a clinical diagnosis of stroke.

INTERVENTION

Eligible trials had to include one these comparisons: VRBR replacing some or all of standard rehabilitation or VRBR used as extra rehabilitation time added to a standard rehabilitation regimen.

OUTCOME MEASURES

Walking speed, balance, mobility and adverse events.

RESULTS

In total, 15 trials involving 341 participants were included. When VRBR replaced some or all of the standard rehabilitation, there were statistically significant benefits in walking speed (MD 0.15 m/s, 95% CI 0.10 to 0.19), balance (MD 2.1 points on the Berg Balance Scale, 95% CI 1.8 to 2.5) and mobility (MD 2.3 seconds on the Timed Up and Go test, 95% CI 1.2 to 3.4). When VRBR was added to standard rehabilitation, mobility showed a significant benefit (0.7 seconds on the Timed Up and Go test, 95% CI 0.4 to 1.1), but insufficient evidence was found to comment about walking speed (one trial) and balance (high heterogeneity).

CONCLUSION

Substituting some or all of a standard rehabilitation regimen with VRBR elicits greater benefits in walking speed, balance and mobility in people with stroke. Although the benefits are small, the extra cost of applying virtual reality to standard rehabilitation is also small, especially when spread over many patients in a clinic. Adding extra VRBR time to standard rehabilitation also has some benefits; further research is needed to determine if these benefits are clinically worthwhile.

Tracking systems for virtual rehabilitation: objective performance vs. subjective experience. A practical scenario

Motion tracking systems are commonly used in virtual reality-based interventions to detect movements in the real world and transfer them to the virtual environment. There are different tracking solutions based on different physical principles, which mainly define their performance parameters. However, special requirements have to be considered for rehabilitation purposes. This paper studies and compares the accuracy and jitter of three tracking solutions (optical, electromagnetic, and skeleton tracking) in a practical scenario and analyzes the subjective perceptions of 19 healthy subjects, 22 stroke survivors, and 14 physical therapists. The optical tracking system provided the best accuracy (1.074 ± 0.417 cm) while the electromagnetic device provided the most inaccurate results (11.027 ± 2.364 cm). However, this tracking solution provided the best jitter values (0.324 ± 0.093 cm), in contrast to the skeleton tracking, which had the worst results (1.522 ± 0.858 cm). Healthy individuals and professionals preferred the skeleton tracking solution rather than the optical and electromagnetic solution (in that order). Individuals with stroke chose the optical solution over the other options. Our results show that subjective perceptions and preferences are far from being constant among different populations, thus suggesting that these considerations, together with the performance parameters, should be also taken into account when designing a rehabilitation system.

Virtual reality for stroke rehabilitation

BACKGROUND

Virtual reality and interactive video gaming have emerged as recent treatment approaches in stroke rehabilitation. In particular, commercial gaming consoles have been rapidly adopted in clinical settings. This is an update of a Cochrane Review published in 2011.

PRIMARY OBJECTIVE

To determine the efficacy of virtual reality compared with an alternative intervention or no intervention on upper limb function and activity.

SECONDARY OBJECTIVE

To determine the efficacy of virtual reality compared with an alternative intervention or no intervention on: gait and balance activity, global motor function, cognitive function, activity limitation, participation restriction and quality of life, voxels or regions of interest identified via imaging, and adverse events. Additionally, we aimed to comment on the feasibility of virtual reality for use with stroke patients by reporting on patient eligibility criteria and recruitment.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (October 2013), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2013, Issue 11), MEDLINE (1950 to November 2013), EMBASE (1980 to November 2013) and seven additional databases. We also searched trials registries and reference lists.

SELECTION CRITERIA

Randomised and quasi-randomised trials of virtual reality ("an advanced form of human-computer interface that allows the user to 'interact' with and become 'immersed' in a computer-generated environment in a naturalistic fashion") in adults after stroke. The primary outcome of interest was upper limb function and activity. Secondary outcomes included gait and balance function and activity, and global motor function.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials based on pre-defined inclusion criteria, extracted data and assessed risk of bias. A third review author moderated disagreements when required. The authors contacted investigators to obtain missing information.

MAIN RESULTS

We included 37 trials that involved 1019 participants. Study sample sizes were generally small and interventions varied. The risk of bias present in many studies was unclear due to poor reporting. Thus, while there are a large number of randomised controlled trials, the evidence remains 'low' or 'very low' quality when rated using the GRADE system. Control groups received no intervention or therapy based on a standard care approach. Intervention approaches in the included studies were predominantly designed to improve motor function rather than cognitive function or activity performance. The majority of participants were relatively young and more than one year post stroke.

PRIMARY OUTCOME

results were statistically significant for upper limb function (standardised mean difference (SMD) 0.28, 95% confidence intervals (CI) 0.08 to 0.49 based on 12 studies with 397 participants).

SECONDARY OUTCOMES

there were no statistically significant effects for grip strength, gait speed or global motor function. Results were statistically significant for the activities of daily living (ADL) outcome (SMD 0.43, 95% CI 0.18 to 0.69 based on eight studies with 253 participants); however, we were unable to pool results for cognitive function, participation restriction, quality of life or imaging studies. There were few adverse events reported across studies and those reported were relatively mild. Studies that reported on eligibility rates showed that only 26% of participants screened were recruited.

AUTHORS' CONCLUSIONS

We found evidence that the use of virtual reality and interactive video gaming may be beneficial in improving upper limb function and ADL function when used as an adjunct to usual care (to increase overall therapy time) or when compared with the same dose of conventional therapy. There was insufficient evidence to reach conclusions about the effect of virtual reality and interactive video gaming on grip strength, gait speed or global motor function. It is unclear at present which characteristics of virtual reality are most important and it is unknown whether effects are sustained in the longer term.