Abstract
Objective:
Physical rehabilitation by virtual reality (VR) gamification is gaining acceptance. This study was designed to verify whether neck movements invoked by a fully immersive VR game environment may be physiotherapist-prescribed rehabilitation exercise.
Methods:
This was a single-visit prospective clinical trial (NCT03104647). Healthy participants put on VR headsets and entered a fully immersive game environment (VRPhysio, XRHealth, Tel Aviv, Israel) that prompted neck movement (flexion, extension, rotation, lateral bend, and combinations repeated twice in random order) accompanied by feedback encouraging correct performance. Four board-certified physiotherapists independently viewed videotapes recorded during the session, identified movements, and determined whether they were recommended as neck rehabilitation exercises.
Results:
Twenty (n = 20) participants (male–female ratio = 13:7; age = 38 ± 14 years old) completed the training session (16 movements per participant). All movements were identified correctly and determined to be appropriate for neck rehabilitation. No adverse events were reported.
Conclusions:
The VRPhysio software invoked movements identified by board-certified physiotherapists as appropriate for neck rehabilitation. The potential advantage of home-based VR gamification of cervical spine rehabilitation programs over common practice in motivating patient adherence warrants evaluation by randomized controlled trials.
Introduction
Dysfunction of the cervical spine has an annual prevalence of 30%–50% in Western society and is associated with considerable pain, disability, and costs.1,2 Physical therapy is the first-line treatment aimed at improving muscle strength and active range of motion (AROM), but often requires considerable commitment by subjects over a long period of time, 3 frequently requiring a home exercise program for a successful outcome.4,5 Adherence to home exercises, however, is often not as high as desired. 6 It is, therefore, imperative to identify new motivational interventions.
Virtual reality (VR) systems are gaining popularity in physiotherapy clinics since they combine fun with interactive training. By providing immediate feedback and gamification, the VR environment enhances motor learning 7 and delays the onset of boredom from the therapeutic exercises, thus improving patient adherence to the rehabilitation program. 8 The use of VR has been studied for a variety of orthopedic-related rehabilitation conditions 9 including patients with chronic neck pain.10–15
Although over-the-shelf products (e.g., Microsoft Xbox® or Nintendo® Wii™) provide a practical way to deliver VR, they are not focused on specific tailored training goals required to complete successful rehabilitation. Moreover, specific exercises invoked by the VR environment do not necessarily promote rehabilitation.
This study was designed to verify whether the neck movements invoked by a fully immersive VR game environment may be considered comparable with those by physiotherapist-prescribed rehabilitation exercises.
Materials and Methods
Study overview
This study was a single-site prospective one-arm study. Eligible healthy participants were asked to sit and put on a VR headset, thereby entering a fully immersive VR game environment (VRPhysio; XRHealth, Tel Aviv, Israel) in which they filled water barrels using neck movements. Procedure-related adverse events were documented throughout the study. Each session was videotaped and subsequently evaluated by four board-certified physiotherapists.
Ethical statement
The trial was approved by the IRB (#0076-17-SZMC) . All patients provided written informed consent before entering the study.
Participants and settings
Participants were recruited at the Shaare Zedek Medical Center (Jerusalem, Israel) during July 2017. Inclusion criteria: Men and women, 18–65 years of age, healthy by self- declaration. Exclusion criteria: (1) history of neck-related disorders (whiplash, disk degeneration disease, or other acute cervical spine conditions); (2) current neck pain; (3) under observation for any health-related issue; (4) recent trauma; (5) oncology background; (6) acute disease/illness; (7) pregnancy; (8) using drugs affecting physical function or balance (i.e., corticosteroids, antipsychotics, and antidepressants); (9) glasses (cannot fit into the headset).
VR software
The VRPhysio N-110 is an FDA-approved software for neck rehabilitation that reliably measures AROM. 16 Coupled with compatible VR hardware (Oculus rift headset), the software tracks motion and kinematics and guides the patients to perform exercises according to goals set by the patients' medical practitioner. The VR system head-mounted display sensor allows interaction in six degrees of freedom: X, Y, Z, roll (side bend = sagittal plane), pitch (flexion/extension = frontal plane), and yaw (rotation = transverse plane). The objects inside the VR software are generated at a frequency of 90 Hz. Thus, by following the smoothly moving objects, the patients move their necks in all anatomical planes.
In this trial, graphic instructions prompted the participant to aim a stream of water to fill barrels using neck movements at a speed of up to 25°/s (see Fig. 1 and Supplementary Video S1), accompanied by feedback that encouraged correct performance. The movements included flexion, extension, rotations, and combinations, for a total of eight movements repeated twice in a random order. The goal for movements from neutral position was 50, 30, and 60° for rotation, lateral flexions, and extension, respectively.
Gamification of neck rotation by fully immersive VR environment.
Study outcomes and statistics
Four board-certified physiotherapists separately viewed the video recordings. They (1) identified each movement seen on the video from a predefined list and (2) determined whether the movement fits a rehabilitation training program for neck-related pathologies.
A sample size of 20 achieves 80.421% power to detect a difference (P1–P0) of 0.3000 using a two-sided exact test with a target significance level of 0.0500. The actual significance level achieved by this test is 0.0414. These results assume that the population proportion under the null hypothesis (P0) is 0.5000. Sample size was calculated using PASS 15.0.4 software (NCSS, LLC, Kaysville, UT, USA).
The primary outcome was the proportion of movements that were determined by the physiotherapist to fit a rehabilitation training program for neck-related pathologies. The success criterion was 80%. The secondary outcome was the rate of procedure-related adverse events.
Results and Discussion
Twenty (n = 20) eligible participants (male–female ratio 13:7; age 38 ± 14 years old) completed the training session. All 16 movements made by each of the 20 participants (320 movements in total) were identified correctly by the physiotherapists and deemed fit for neck rehabilitation. The movements of one of the participants were characterized as “not smooth” but were nonetheless identified. No adverse events were reported throughout the study.
In a meta-analysis by Gumaa et al., VR was not found beneficial compared with exercises for orthopedic rehabilitation. 9 However, more than half of the studies used off-the-shelf software (i.e., Nintendo Wii, Xbox). The software used in this study was developed in collaboration with physiotherapists and spine specialists, which may explain the high level of positive results (100% movements determined fit for rehabilitation). Adherence to home exercises is important for the success of the rehabilitation program.4–6
The addition of a motivational tool, verified as rehabilitative, is critical. Moreover, patient involvement and positive attitude are very important for achieving positive clinical outcomes. In previous studies based on VR software tailored for neck rehabilitation, patients with chronic neck pain reported a high level of satisfaction and positive attitude toward the VR intervention.10,13,17
Limitations
This study did not include patients with neck dysfunction or patients who could not follow written instructions. Kinematic information was not collected as it was not one of the study goals.
Conclusions
In a group of healthy participants, the VRPhysio software was shown to invoke movements that were identified by board-certified physiotherapists as fit for neck rehabilitation, with no adverse events. The potential advantage of home-based VR gamification of cervical spine rehabilitation programs over common practice in motivating patient adherence warrants evaluation by randomized controlled trials.
Footnotes
Acknowledgment
We thank Miss Noa Makhervax for technical assistance.
Authors' Contributions
Authors jointly designed the study, conducted, and supervised all study procedures, interpreted the data, critically reviewed the article for important intellectual content, approved the final article as submitted, and agree to be accountable for all aspects of the work. L.G. was the study director, performed the statistical analysis, and wrote the initial draft. O.W. contributed with conceptualization, methodology, and medical software. Y.B. was the principal investigator, recruited patients, and supervised clinical evaluations.
Author Disclosure Statement
L.G. was paid as a scientific consultant. O.W. is an XRHealth employee. Y.B. owns stock in XRHealth.
Funding Information
This study was sponsored by XRHealth Ltd. These studies were supported in part by The Stuart Roden Family Research Fund, London, United Kingdom; The Saul and Joyce Brandman Fund for Cardiovascular Research; The Alexander Grass Family Research Fund; The Dr. Bruce and Baila Waldholtz Research Fund; and The Dr. Martin and Grace Rosman Research Fund, Faculty of Medicine, The Hebrew University of Jerusalem, Israel.
References
Supplementary Material
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