Applications of Head-Mounted Displays for Virtual Reality in Adult Physical Rehabilitation: A Scoping Review

The Use of Head-Mounted Display Systems for Upper Limb Kinematic Analysis in Post-Stroke Patients: A Perspective Review on Benefits, Challenges and Other Solutions

In recent years, there has been a notable increase in the clinical adoption of instrumental upper limb kinematic assessment. This trend aligns with the rising prevalence of cerebrovascular impairments, one of the most prevalent neurological disorders. Indeed, there is a growing need for more objective outcomes to facilitate tailored rehabilitation interventions following stroke. Emerging technologies, like head-mounted virtual reality (HMD-VR) platforms, have responded to this demand by integrating diverse tracking methodologies. Specifically, HMD-VR technology enables the comprehensive tracking of body posture, encompassing hand position and gesture, facilitated either through specific tracker placements or via integrated cameras coupled with sophisticated computer graphics algorithms embedded within the helmet. This review aims to present the state-of-the-art applications of HMD-VR platforms for kinematic analysis of the upper limb in post-stroke patients, comparing them with conventional tracking systems. Additionally, we address the potential benefits and challenges associated with these platforms. These systems might represent a promising avenue for safe, cost-effective, and portable objective motor assessment within the field of neurorehabilitation, although other systems, including robots, should be taken into consideration.

Limitations and solutions of low cost virtual reality mirror therapy for post-stroke patients

Mirror therapy is applied to reduce phantom pain and as a rehabilitation technique in post-stroke patients. Using Virtual Reality and head-mounted displays this therapy can be performed in virtual scenarios. However, for its efficient use in clinical settings, some hardware limitations need to be solved. A new system to perform mirror therapy in virtual scenarios for post-stroke patients is proposed. The system requires the patient a standalone virtual reality headset with hand-tracking features and for the rehabilitator an external computer or tablet device. The system provides functionalities for the rehabilitator to prepare and follow-up rehabilitation sessions and a virtual scenario for the patient to perform rehabilitation. The system has been tested on a real scenario with the support of three experienced rehabilitators and considering ten post-stroke patients in individual sessions focused on upper limb motor rehabilitation. The development team observed all the sessions and took note of detected errors regarding technological aspects. Solutions to solve detected problems will be proposed and evaluated in terms of feasibility, performance cost, additional system cost, number of solved issues, new limitations, or advantages for the patient. Three types of errors were detected and solved. The first error is related to the position of the hands relative to the head-mounted display. To solve it the exercise area can be limited to avoid objectives that require turning the head too far. The second error is related to the interaction between the hands and the virtual objects. It can be solved making the main hand non-interactive. The last type of error is due to patient limitations and can be mitigated by having a virtual hand play out an example motion to bring the patient's attention back to the exercise. Other solutions have been evaluated positively and can be used in addition or instead of the selected ones. For mirror therapy based on virtual reality to be efficient in post-stroke rehabilitation the current head-mounted display-based solutions need to be complemented with specific strategies that avoid or mitigate the limitations of the technology and the patient. Solutions that help with the most common issues have been proposed.

Immersive Virtual Reality in Basic Point-of-Care Ultrasound Training: A Randomized Controlled Trial

This study was aimed at comparing the learning efficacy of a traditional instructor-led lesson with that of a completely virtual, self-directed lesson in immersive virtual reality (IVR) in teaching basic point-of-care ultrasound (PoCUS) skills. We conducted a blinded, non-inferiority, parallel-group, randomized controlled trial in which final-year medical students were randomized to an instructor-led (n = 53) or IVR (n = 51) lesson. Participants' learning efficacy was evaluated by blinded assessors, who rated each participant's performance using the Objective Structured Assessment of Ultrasound Skills (OSAUS) assessment tool.The mean total scores for participants were 11.0 points (95% confidence interval: 9.8-12.2) for the instructor-led lesson and 10.3 points (95% confidence interval: 9.0-11.5) for the IVR lesson. No significant differences were observed between the groups with respect to total score (p = 0.36) or subgroup objectives of the OSAUS score (p = 0.34 for familiarity, p = 0.45 for image optimization, p = 0.96 for systematic approach and p = 0.07 for interpretation). Maintenance costs for both courses were estimated at 400 euros each. Startup costs for the instructor-led course were estimated 16 times higher than those for the IVR course. The learning efficacy of an instructor-led lesson on basic US did not differ significantly from that of a self-directed lesson in IVR, as assessed using the OSAUS. The results suggest that IVR could be an equivalent alternative to instructor-led lessons in future basic US courses, but further research is warranted to clarify the role of IVR in PoCUS courses.

Immersion Therapy with Head-Mounted Display for Rehabilitation of the Upper Limb after Stroke-Review

Immersive virtual therapy technology is a new method that uses head-mounted displays for rehabilitation purposes. It offers a realistic experience that puts the user in a virtual reality. This new type of therapy is used in the rehabilitation of stroke patients. Many patients after this disease have complications related to the upper extremities that limit independence in their everyday life, which affects the functioning of society. Conventional neurological rehabilitation can be supplemented by the use of immersive virtual therapy. The system allows patients with upper limb dysfunction to perform a motor and task-oriented training in virtual reality that is individually tailored to their performance. The complete immersion therapy itself is researched and evaluated by medical teams to determine the suitability for rehabilitation of the upper limb after a stroke. The purpose of this article is to provide an overview of the latest research (2019-2022) on immersive virtual reality with head-mounted displays using in rehabilitation of the upper extremities of stroke patients.

The effectiveness of immersive virtual reality in physical recovery of stroke patients: A systematic review

Background

Over the past few years, technological innovations have been increasingly employed to augment the rehabilitation of stroke patients. Virtual reality (VR) has gained attention through its ability to deliver a customized training session and to increase patients' engagement. Virtual reality rehabilitation programs allow the patient to perform a therapeutic program tailored to his/her needs while interacting with a computer-simulated environment.

Purpose

This study aims to investigate the effectiveness of a fully immersive rehabilitation program using a commercially available head-mounted display in stroke patients.

Methods

A systematic search was conducted in three databases, namely, PubMed, Google Scholar, and PEDro. Four hundred thirty-two references were identified. The keywords used for the literature search were in English, which are given as follows: immersive, virtual reality, neurorehabilitation, stroke, and head-mounted display. Additionally, applicable articles were identified through screening reference lists of relevant articles.

Results

Only 12 studies used head-mounted display for immersing the patient into the virtual world. Apart from the feasibility of this new technology, a range of benefits were identified, especially in terms of functional ability as measured by FIM or Barthel, the Action Research arm Test, Box and Block Test, Fugl-Meyer assessment of physical performance, strength, and balance outcomes.

Conclusion

The results from this review support the potential beneficial effect of fully immersive virtual reality in the rehabilitation of stroke patients, maximizing recovery through increased motivation and adherence.

Overground Walking in a Fully Immersive Virtual Reality: A Comprehensive Study on the Effects on Full-Body Walking Biomechanics

Virtual reality (VR) is an emerging technology offering tremendous opportunities to aid gait rehabilitation. To this date, real walking with users immersed in virtual environments with head-mounted displays (HMDs) is either possible with treadmills or room-scale (overground) VR setups. Especially for the latter, there is a growing interest in applications for interactive gait training as they could allow for more self-paced and natural walking. This study investigated if walking in an overground VR environment has relevant effects on 3D gait biomechanics. A convenience sample of 21 healthy individuals underwent standard 3D gait analysis during four randomly assigned walking conditions: the real laboratory (RLab), a virtual laboratory resembling the real world (VRLab), a small version of the VRlab (VRLab-), and a version which is twice as long as the VRlab (VRLab+). To immerse the participants in the virtual environment we used a VR-HMD, which was operated wireless and calibrated in a way that the virtual labs would match the real-world. Walking speed and a single measure of gait kinematic variability (GaitSD) served as primary outcomes next to standard spatio-temporal parameters, their coefficients of variant (CV%), kinematics, and kinetics. Briefly described, participants demonstrated a slower walking pattern (-0.09 ± 0.06 m/s) and small accompanying kinematic and kinetic changes. Participants also showed a markedly increased gait variability in lower extremity gait kinematics and spatio-temporal parameters. No differences were found between walking in VRLab+ vs. VRLab-. Most of the kinematic and kinetic differences were too small to be regarded as relevant, but increased kinematic variability (+57%) along with increased percent double support time (+4%), and increased step width variability (+38%) indicate gait adaptions toward a more conservative or cautious gait due to instability induced by the VR environment. We suggest considering these effects in the design of VR-based overground training devices. Our study lays the foundation for upcoming developments in the field of VR-assisted gait rehabilitation as it describes how VR in overground walking scenarios impacts our gait pattern. This information is of high relevance when one wants to develop purposeful rehabilitation tools.

The Effects of Visual Backgrounds in the Virtual Environments on the Postural Stability of Standing

A photorealistic scene in a head mount display (HMD) is considered high fidelity and associated with postural stability similar to that in the real world, but the effects of visual background under different standing conditions have not been examined. Thirty-four healthy adults performed four standing (standardized, narrow, tandem and one-leg) tasks in three scenes with an HMD, while viewing one of three scenes: a real room (real scene, RS), a photorealistic scene (VrS) and a blank scene (BS). The effects of the visual scenes and standing tasks on sway parameters were analyzed. Romberg quotients (RQs) of the sway parameters were compared between RS and VrS with reference to BS to compare visual contribution to posture stability. Sway parameters were similar during all three scenes during the standardized and narrow standing tasks, but higher in VrS and BS conditions than in the RS condition during the tandem and one-leg standing tasks. The effects of visual scenes on postural stability showed a significant interaction with the standing tasks. The BS/VsR and BS/RS ratios were close to 1.0 for the standardized and narrow standing tasks, and the magnitude of increase was lower for BS/VsR than BS/RS during the tandem and one-leg standing tasks, indicating different levels of visual dependence. The effects of virtual scenes on postural stability were task-dependent. Adjusting the amount of visual stimuli and choosing tasks with higher postural demands may result in synergic effects, but the influence of visual environments should be examined with consideration of visual targeting.

Procedural Learning through Action Observation: Preliminary Evidence from Virtual Gardening Activity in Intellectual Disability

Intellectual disability (ID) compromises intellectual and adaptive functioning. People with an ID show difficulty with procedural skills, with loss of autonomy in daily life. From an embodiment perspective, observation of action promotes motor skill learning. Among promising technologies, virtual reality (VR) offers the possibility of engaging the sensorimotor system, thus, improving cognitive functions and adaptive capacities. Indeed, VR can be used as sensorimotor feedback, which enhances procedural learning. In the present study, fourteen subjects with an ID underwent progressive steps training combined with VR aimed at learning gardening procedures. All participants were trained twice a week for fourteen weeks (total 28 sessions). Participants were first recorded while sowing zucchini, then they were asked to observe a virtual video which showed the correct procedure. Next, they were presented with their previous recordings, and they were asked to pay attention and to comment on the errors made. At the end of the treatment, the results showed that all participants were able to correctly garden in a real environment. Interestingly, action observation facilitated, not only procedural skills, but also specific cognitive abilities. This evidence emphasizes, for the first time, that action observation combined with VR improves procedural learning in ID.

Virtual reality for pediatric periprocedural care

PURPOSE OF REVIEW

Commercial availability of virtual reality headsets and software has exponentially grown over the last decade as it has become more sophisticated, less expensive, and portable. Although primarily used by the general public for entertainment, virtual reality has been adopted by periprocedural clinicians to improve patient experiences and treatments. The purpose of this review is to explore recently reported evidence for virtual reality effectiveness for pediatric periprocedural care and discuss considerations for clinical implementation.

RECENT FINDINGS

In the preprocedure setting, practitioners use virtual reality to introduce children to periprocedural environments, distract attention from preprocedural vascular access, and increase cooperation with anesthesia induction. Intraprocedure, virtual reality decreases sedation requirements, and in some instances, eliminates anesthesia for minor procedures. Virtual reality also augments pain reduction therapies in the acute and extended rehabilitation periods, resulting in faster recovery and improved outcomes. Virtual reality seems to be well treated for pediatric use, given close clinical care and carefully curated content.

SUMMARY

Given the multiple clinical applications of virtual reality to supplement pediatric periprocedural care, practitioners should consider developing clinical programs that reliably provide access to virtual reality. Future research should focus on identification of patient characteristics and types of software that yield optimal patient outcomes.