Effects of Virtual Reality Training Using Xbox Kinect on Balance,Postural Control,and Functional Independence in Subjects with Stroke

Introduction

Stroke is the second most common cause of death and third most common cause of disability globally. ¹ The global burden of stroke has increased from the past two decades, specifically in developing countries with higher incidence in males as compared with females. In Pakistan, incidence of stroke is 250/100,000 with 350,000 new cases arising every year.^2,3 These rising numbers are indicative of enormous disabilities resulting from stroke. Sedentary behaviors, least active lifestyle, genetic factors, and stress contribute to development of this disease, and may result in worst imagined consequences of sensory and motor deficits along with balance, coordination, and other neurological deficits, which can limit the patient's level of independence and his social freedom.^4,5

With the advancements in health care research and facilities, the perspectives to treat the diseases are changing rapidly. Virtual reality is one of those advanced technologies being incorporated in health care for minimizing disabilities and has been found to be beneficial and cost-effective for subjects with stroke. ⁶

Xbox Kinect is a cost-effective virtual gaming technology that is being widely used for rehabilitation purposes. It has a commercially designed console and sensor that detects the person's position and movements and allowing him/her to perform activities in a virtual environment. It has been found feasible and safe in subjects with stroke. It has been found to improve motor control, balance, and functional recovery after stroke. ⁷ Literature suggests that Xbox Kinect training has positive effects on muscle tone, muscle strength, and activities of daily living. ⁸ Xbox is an effective way to improve motor function and postural control in stroke survivors. ⁹ Considering the growing incidence of stroke in Pakistan and disabilities associated with it, the study aims to determine the effects of virtual reality training using Xbox Kinect on balance, postural control, and functional independence in subjects with stroke.

Materials and Methods

The parallel double-blind randomized control trial was started on August 1, 2019, after gaining approval from ethical committee of Shifa International Hospital, Islamabad, Pakistan (Reg No. 169-659-2019). The procedures used were in accordance with ethical standards given in Declaration of Helsinki of 1975, as revised in 2000. The sample size of 40 subjects, with 20 in each group was calculated through G power samples size calculator keeping the margin of error to 0.05, confidence interval at 95%, and effect size 0.25. Informed written and verbal consent was taken from all the participants before their inclusion to the study.

Subjects were assessed for inclusion criteria of being stable vitally, suffered from ischemic or hemorrhagic stroke at least 3 months back, Berg balance score of 21–40, able to stand for at least 10 seconds independently, mild to moderately affected upper limb functions, and excluded if they had any synergy and surgical maneuver in past year. The process led to recruitment of 41 participants who fulfilled the criteria; they were further divided into experimental (n = 20) and control (n = 21). Participants and outcome assessor were kept blinded about the intervention group. Subjects were divided into two groups by concealed envelope method: intervention and control group.

Intervention group received exergaming by Xbox Kinect, 3 days a week for 30 minutes for 8 weeks. The intervention comprised Kinect sport, Kinect adventure, your shape fitness evolved, and carnival. The sequence in which the subjects played games was Kinect sport, Kinect adventure, carnival, and your shape fitness evolved. Kinect sport and adventure were played for 2 weeks initially, and then carnival and your shape were added. The games allowed a specific combined body movement with weight shifts and direction changes. The games were chosen to stimulate the components to improve balance and mobility.

The control group was given exercises comprising balance training, upper limb strengthening, and core strengthening, 3 days a week for 8 weeks. The exercise sequence was from simple to complex. Ten minutes warm up and cool down sessions were also given before and after intervention in both groups. All the sessions were provided in a safe and participant-friendly environment under close supervision of a physical therapist. Berg balance scale (BBS), timed up and go (TUG), trunk impairment scale (TIS), and functional independence measure (FIM) were the outcome measures.

The BBS consists of 14-items that quantitatively measure the ability to maintain balance in multiple neurological disorders, including stroke, either statically or while performing various functional movements and assess the risk for falls through direct observation of their performance. Test–retest reliability of BBS is 0.99, inter- and intrarater reliability is 0.97 and 0.98, respectively, whereas Cronbach's alpha is 0.98. The score ranges from 0 to 4, with a score of 0 representing an inability to complete the task and a score of 4 representing independent item completion.

Out of 56 possible points, a score of 0–20 represents balance impairment, 21–40 represents acceptable balance, and 41–56 represents good balance. ¹⁰ For TUG test, the participants were asked to rise from a standard chair, walk a 3-m distance, turn, walk back to the chair, and sit down to assess their functional mobility. Test–retest reliability of TUG is 0.96 in stroke population. ¹¹ TIS evaluates motor impairment of the trunk after stroke with scores for static and dynamic sitting balance as well as trunk co-ordination ranging from 0 to 23. It also aims to score the quality of trunk movement.

The reliability of TIS is 0.96, whereas Cronbach's alpha is 0.89. ¹² The FIM consists of 18 items in total with 7 levels developed to assess severity of disability and serves as medical rehabilitation functional outcome. FIM has reliability and validity of 0.96 and 0.88, respectively, in stroke. ¹³ Subjects were reassessed after 8 weeks of intervention. The participants were motivated and encouraged to continue their participation and activities for better outcomes, which led to their adherence to the treatment sessions. There was one dropout from the control group after 3 weeks of intervention, with the subject travelling to another city. Figure 1; CONSORT flow diagram shows the detailed study procedure.

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FIG. 1.

CONSORT flow diagram.

Statistical analysis was performed using SPSS v21. The normality testing was done, and all the measures had a Shapiro–Wilk value of <0.05, on the basis of which the longitudinal within group analysis was performed using paired sample t test and the between-group analysis was done through independent sample t test. Effect size was also calculated for Cohen's d value.

Results

Mean age of the participants of Xbox group and exercise group were 58.6 ± 3.3 and 58.1 ± 4.3 years, respectively, whereas the poststroke duration was 7.2 ± 1.8 and 6.3 ± 2.1 months for Xbox and exercise group, respectively. Population characteristics are mentioned in Table 1. Within group and between group analyses are described in Table 2. Cohen's d values are also mentioned in Table 2.

Within group analysis showed significant differences in both groups. Between group results are also significant for TUG, TIS, and FIM, whereas in BBS there was no significant difference reported (P = 0.08). Cohen's d was also calculated to see the effect size of interventions. The Cohen's d was medium for BBS (0.45), whereas it was large for TUG, TIS, and FIM (>1.0).

Discussion

The aim of this study was to determine the effects of virtual reality training using Xbox Kinect on balance, postural control, and functional independence in subjects with stroke. The study comprised an 8-week intervention using Xbox Kinect versus balance training, upper limb strengthening, and core strengthening. The study found that Wii Fit improved functional mobility, independence, and trunk coordination extension in the stroke patients, whereas balance could be equally improved from Wii Fit and exercises.

This study showed no difference between treatment strategies on functional balance and is contradictory to a study conducted by In et al., which provided evidence that as compared with control group, improvement in functional balance was markedly better in the virtual reality (VR) training group. ¹⁴ This may be due to the relatively less age difference of participants in both groups of our study compared to the study conducted earlier where mean age of participants in control group was less opposed to intervention group.

There was also a greater improvement in dynamic balance in chronic stroke patients undergoing virtual reality-based training previously, ¹⁵ and this may be attributed to physical therapy and occupational therapy inculcated in both experimental and control groups. In a recent study, comparing the effects of Wii Fit combined with conventional physical therapy on the one hand, and conventional physical therapy alone on balance in chronic stroke patients in the other, showed that the former treatment approach had promising results. In addition, the said treatment approach showed improved results in functional mobility as well as activities of daily living when virtual reality using Nintendo Wii was incorporated to conventional therapy. ¹⁶

Furthermore, neither of the two treatment approaches―treatment based on VR and conventional therapy used in this study―was preferable over the other for the treatment of balance in patients with chronic stroke. Both treatment protocols were found to be effective, which is in line with studies conducted earlier.^17,18

Evidence from this study is in line with the previous study conducted by Park et al., which was also supportive of VR training using Xbox Kinect for improving motor function and mobility during stroke rehabilitation. ⁹ This study showed that VR positively influenced functional mobility measured by FIM, which is in line with previous studies.^15,19 There was also greater improvement in the same group for independence in activities of daily living and trunk coordination in the participants.

However, in a study conducted in 2013, no statistically significant difference was found for the aforementioned parameters in the intergroup comparison between Wii Fit with conventional physical therapy and conventional physical therapy alone. ²⁰ In this study, the reason could be that the treatment protocol for both groups lasted for 8 weeks with three sessions per week as compared in the previous study, which lasted for 5 weeks with only two sessions per week. In the intragroup analysis for both studies, all groups demonstrated a significant improvement in all variables studied.

Significant improvement is evident on functional independence in the group receiving Xbox training in this study. However, no significant difference is shown between both treatment groups regarding functional independence; performing activities of daily living, as per the study by Lee, had almost twice the smaller sample size than this study with participants having a relatively greater stroke duration in the control group. ⁸

This study involved major components: balance, mobility, functional independence, and trunk control, which are necessary for independent activity levels in subjects with stroke. However, the major limitation is that it does not include any objective outcome measure. Using any objective measure may result in much improved results.

Conclusion

Xbox Kinect was found to improve functional mobility, independence, and trunk coordination in the stroke patients, whereas balance could be equally improved from Xbox Kinect and exercises.