Virtual Reality as a Therapy Tool for Walking Activities in Pediatric Neurorehabilitation: Usability and User Experience Evaluation.

Background: Many essential walking activities in daily life, such as crossing a street, are challenging to practice in conventional therapeutic settings. Virtual environments (VEs) delivered through a virtual reality (VR) head-mounted display (HMD) would allow training such activities in a safe and attractive environment. Furthermore, the game-like character and high degree of immersion in these applications might help maintain or increase children's motivation and active participation during the rehabilitation process.

Objective: This study aimed to investigate the usability, user experience, and acceptability of an immersive VE experienced through a VR HMD to train everyday life walking activities in pediatric neurorehabilitation.

Methods: In a cross-sectional study, 21 youths (median age 12.1 years; range 6.8-17.7 years) with a neuromotor impairment undergoing inpatient or outpatient neurorehabilitation tested a VE experienced through the VR HMD Oculus Quest. The participants, accompanied by their physiotherapists, moved freely around a 4.4 by 10-meter VE, displaying a magical forest and featuring various gamified everyday activities in different game designs. Using their hands, represented in the VE, the participants could interact with the virtual objects placed throughout the VE and trigger visual and auditory feedback. Symptoms of cybersickness were checked, and usability, user experience, and acceptability were evaluated using customized questionnaires with a visual analog scale for youths and a 5-point Likert scale for their therapists.

Results: None of the participants reported any signs of cybersickness after 20 minutes of VR HMD exposure time. They rated comfort (median 10/10) and movement ability (median 10/10) with the VR HMD as high. The VE was perceived as being really there by the majority (median 8/10), and the participants had a strong feeling of spatial presence in the VE (median 9.5/10). They enjoyed exploring the virtual world (median 10/10) and liked this new therapy approach (median 10/10). Therapists' acceptance of the VR HMD was high (4/5). There were 5 patients that needed more support than usual, mainly for supervision, when moving around with the VR HMD. Otherwise, therapists felt that the VR HMD hardly affected their patients' movement behavior (median 4.75/5), whereas it seemed to increase their level of therapy engagement (median 4/5) compared to conventional physiotherapy sessions.

Conclusions: This study demonstrates the usability of an immersive VE delivered through a VR HMD to engage youths in the training of everyday walking activities. The participants' and therapists' positive ratings on user experience and acceptance further support the promising application of this technology as a future therapeutic tool in pediatric neurorehabilitation.