Virtual Reality for Stroke Rehabilitation

Can virtual reality help this patient?

Mr Silva is a 72-year-old man who had a stroke due to a middle cerebral artery territory infarct. Prior to his stroke, he was retired, lived independently with his wife in the community, and walked unaided. He was admitted to an inpatient stroke rehabilitation unit 2 weeks after his stroke, and at that time he scored 25/30 on the Mini-Mental State Examination,¹⁸ indicating normal cognitive function.

On physical examination, Mr Silva had right-sided weakness. To measure his upper limb function, his physical therapist used the Fugl-Meyer Scale¹⁹ and the Box and Block Test.²⁰ On the Fugl-Meyer Scale (upper limb section), he scored 41/66 points, indicating moderate motor impairment.¹⁷ On the Box and Block Test, he moved 23 blocks in 60 seconds, indicating moderate limitation in hand function.^21–24 The normative value (average performance) on the Box and Block Test for a man aged 72 years using his right hand is 68 blocks (SD=8).²⁵

On assessment of his walking at this time, Mr Silva was able to walk short distances indoors with standby supervision of one person and was unable to walk outdoors. To measure his mobility, his physical therapist conducted the Short Physical Performance Battery,²⁶ on which he scored 2/12. For the balance subscale, he scored 0/4. He was able to stand in side-by-side stance unassisted, but only for 8 seconds; thus, semi-tandem and tandem stance were not attempted. For the walking subscale, he scored 1/4 and was able to walk 4 m in 21 seconds (0.19 m/s). For the sit-to-stand subscale, he scored 1/4 and was able to stand up without using his hands 5 times in 17.5 seconds.

How did the results of the Cochrane review apply to Mr Silva?

During the initial rehabilitation assessment, Mr Silva expressed motivation for additional exercise and an interest in technology. The physical therapist, therefore, considered whether Mr Silva would benefit from the addition of virtual reality as an adjunct to usual therapy to improve his upper limb function and mobility. She, therefore, posed the clinical question: In a 72-year-old man who is 2 weeks poststroke, will virtual reality (in addition to conventional therapy) improve upper limb function and mobility? Thus, the review by Laver et al¹⁶ was identified and provided useful information for this patient.

The review¹⁶ included studies with both male and female participants with a range of upper limb severities (for studies evaluating the upper limb) and independent walkers (for studies evaluating mobility), with study mean ages of 46 to 75 years. The majority of studies recruited participants who were more than 6 months poststroke; however, some studies recruited participants earlier poststroke, and subgroup analysis showed greater benefit in upper limb function for studies recruiting participants within 6 months of stroke compared with more than 6 months. Mr Silva was a 72-year-old man 2 weeks after stroke with moderate upper limb limitations who could walk indoors with supervision, which is similar to the population included in the review.

The virtual reality intervention in the review¹⁶ was composed of different gaming systems (eg, Nintendo Wii, GestureTek IREX), of which included studies focused on different training aspects of rehabilitation (eg, reaching and manipulation, standing and walking). The physical therapist working with Mr Silva opted to use the Nintendo Wii gaming console (Nintendo Wii Seventh generation, RVL-001, Foxconn), as this device was easy to access, there were suitable games to target upper limb and hand function and overall mobility, and the Cochrane review showed no significant difference between commercially available systems and more expensive custom-made systems. The intervention was applied in a private room of the hospital, without any distractions. As most studies included in the review¹⁶ provided between 11 and 20 hours of therapy (range=>5 hours to >21 hours), the physical therapist decided to deliver a program of 1 hour of supervised virtual reality sessions, 5 times per week for 3 weeks (15 hours total). The games selected were from the Wii Sports, Wii Fit, and Cooking Mama software. Games were selected to address activity limitations (eg, Penguin slide game from Wii Fit to improve loading the right leg for standing and walking) and were modified where necessary to better tailor the game to suit Mr Silva's current abilities (eg, Tightrope game from Wii Fit changed to a step-touch exercise to a block). The therapist used about 4 to 6 different games per session, with Mr Silva playing each game between 3 to 6 times depending on the length and difficulty of the game. Before commencing the training, the physical therapist introduced Mr Silva to the virtual reality system and instructed him on how to move his body to control the movements of the avatar within the games. The physical therapist also assisted Mr Silva in holding the controls (Wiimote and Nunchuk) and directed the correct movements of his arm and hand when necessary.

The virtual reality therapy was accompanied with 1 to 2 hours of conventional physical therapy (usual care) 5 times per week (prior to the virtual reality sessions) and with other rehabilitation provided by the multidisciplinary team. Conventional physical therapy included exercises to address physical impairments (eg, strength training to address weakness) and task-specific practice to address activity limitations, delivered in a combination of one-on-one, semisupervised and group therapy sessions.

A number of different outcome measures were reported in the Cochrane review, most likely due to the diverse interventions addressing different activity limitations (eg, hand function versus walking). For our case study (Mr Silva), the aim of therapy was to improve upper limb function and mobility. We, therefore, chose the same (Fugl-Meyer Scale and Box and Block Test) or similar (Short Physical Performance Battery) outcome measures as reported in the review.¹⁶

How well do the outcomes of the treatment provided to the patient match those suggested in the review?

After the 3-week program of virtual reality and conventional therapy, Mr Silva completed 14 sessions (93%), missing 1 session due to feeling too fatigued, and showed excellent adherence to the intervention. He showed improvement in upper limb function, with his Fugl-Meyer Upper Extremity Scale score increasing from 41 to 46 points. This improvement aligns with the Cochrane review,¹⁶ and the increase was greater than the 4-point change considered to reflect a clinically important difference for individuals with stroke.²⁷ Mr Silva also demonstrated improvement in hand function, with his posttraining Box and Block Test score increasing from 23 to 26 blocks. This improvement is in accordance with the Cochrane review,¹⁶ but it is lower than the 5.5-point change considered to reflect a clinically important difference for individuals with stroke.²³

Mr Silva also improved his mobility after the 3-week training, as demonstrated by his Short Physical Performance Battery score increasing from 2 to 8 points. For the balance subscale scale, he scored 4/4, as he was now able to stand with his feet side-by-side, semitandem, and tandem stance for 10 seconds each. For the walking subscale, he still scored 1/4 but was now able to walk 4 m in 11 seconds (0.36 m/s). For the sit-to-stand subscale, he scored 3/4 and was able to stand up without using his hands 5 times in 11.3 seconds. The minimal detectable change on the Short Physical Performance Battery is 2.9 points for elderly people,²⁸ although it is not clear whether it is the same for patients with stroke. This mobility improvement exceeded the systematic review findings, which did not show a difference between groups. This discrepancy may be explained by the very low quality of evidence for this comparison, which represents uncertainty about the effect estimate and a lack of studies investigating the effects on walking of virtual reality early after stroke.

Can you apply the results of the review to your own patient?

The systematic review results applied well to Mr Silva, who exhibited limitations in reaching and manipulating, standing, and walking. The studies included in the Cochrane review by Laver et al¹⁶ included relatively young people after stroke and often excluded people with cognitive impairment, aphasia, apraxia, and visual impairments; thus, the results may not generalize to this subset of people after stroke.

The studies included in the review focused on different training aspects of rehabilitation, including upper limb, activity, lower limb, and balance and walking; global motor function; and visual perceptual retraining. The strongest evidence was in improving upper limb function, particularly in people within 6 months of stroke. The evidence, however, is only of low quality due to small sample sizes and unclear bias within the study designs, which means that further research is very likely to change the effect estimates and that we lack confidence in the effect estimate. For other aspects of rehabilitation (eg, walking, mobility), the evidence from the review was less clear, with very little confidence in the effect estimates provided by the very low-quality evidence. However, a more recent systematic review,²⁹ which incorporated 6 new studies^30–35 published after the Cochrane review search, was conducted and reported improvements in walking speed, balance, and mobility when virtual reality was compared with standard rehabilitation. The evidence, however, was less clear when virtual reality was used as an adjunct to standard rehabilitation.

The virtual reality systems used in the studies included in the review ranged from inexpensive commercially available recreational gaming systems to more expensive, commercially available rehabilitation systems to expensive customized virtual reality systems that are not readily available. Subgroup analysis in the review did not show any differences in upper limb function when comparing different types of virtual reality systems. These analyses, however, were limited by the number of studies using the different systems, suggesting that further research is warranted to understand key features important in virtual reality systems. As such, as we demonstrated in our case study that due to the limited quality of evidence available, the use of commercially available recreational gaming systems appears to be reasonable at this time as an affordable way to provide virtual reality as part of rehabilitation.

What can be advised based on the results of this systematic review?

The Cochrane systematic review¹⁶ showed low- to very low-quality evidence that virtual reality can be benefical for people after stroke with activity limitations in reaching and manipulation; the benefits on standing and walking are less clear. In addition, minimal adverse events were reported and considered minor (eg, transient dizziness). The rehabilitation program proposed in this case study consisted of virtual reality used in addition to usual care. Mr Silva improved his upper limb function, walking, and balance, which may or may not have been due to the addition of virtual reality to his usual care and taking into account the natural recovery after stroke. It is possible that people after stroke, like Mr Silva, can benefit from virtual reality as an adjunct to usual care.

Further research is needed, as virtual reality is still a new addition to physical therapy treatment options and the low and very low quality of the evidence means there is still uncertainty in the benefits. Trials including cost-effectiveness analysis and studies evaluating the acceptibility and feasibility of virtual reality are needed to guide the implementation of these systems into clinical practice. The current evidence does not support clinical services investing and utilizing expensive virtual reality systems or replacing current evidence-based rehabilitation interventions. However, it would appear reasonable and safe to incorporate accessible virtual reality systems as part of the rehabilitation program for a person after stroke, taking into account the person's preferences for this type of intervention.