Today, falls constitute a substantial health problem, especially in the elderly, and the diagnostic tests used by clinicians present often a low sensitivity and specificity. This is the case for the Timed Up and Go test which lacks contextualization with regard to everyday life limiting the relevance of its diagnosis. Virtual reality enables the creation of immersive, reproducible and secure environments, close to situations encountered in daily life, and as such could improve falling risk assessment. This study aims to evaluate the effect of immersive virtual reality by wearing a virtual reality headset with a non-disturbing virtual environment compared to real world on the Timed Up and Go test completion. Thirty-one elders (73.7 ± 9 years old) volunteered to participate in the study and the mean times and number of steps to complete a Timed Up and Go were compared in two conditions: actual-world clinical and virtual reality conditions. The results showed that the mean completion times and most of the mean number of steps of the Timed Up and Go in virtual reality condition were significantly different to those in clinical condition. These results suggest that there is a virtual reality effect and this effect is significantly correlated to the time taken to complete the Timed Up and Go. This information will be of interest to quantify the potential part of virtual reality effect on the motor control, measured in a virtual task using virtual controlled disturbances.

<b><i>Background/Aims:</i></b> Falling among the elderly is a major public health issue, especially with the advancing age of the baby boomers. The fall risk assessment tests for many lack a context that would bring them closer to everyday life. Thus, immersive virtual reality, which makes it possible to simulate everyday situations, could make it possible to strengthen the quality of the assessment of the risk of falls. However, it is necessary to understand how the use of a virtual reality device influences the motor control of elderly participants. If vestibular physiotherapists use VR to virtualize their tools, what impact would a visual simulation of movement have on motor control in a locomotor task, if this simulation were plausible? <b><i>Methods:</i></b> Sixty-two elders (70.8 ± 6.7 years old) completed a Timed Up and Go task under 3 conditions: real, virtual reality, and virtual reality with visual and sound movement information. The virtual reality task takes place in a train either stationary at a station or in uniform linear motion. The time and number of steps were recorded using video, and comparisons between conditions were made using Friedman’s test. <b><i>Results:</i></b> The results show a significant increase in the time and number of steps in “virtual reality” condition compared to the “real” condition. They do not show significant differences between the 2 virtual conditions. <b><i>Conclusion:</i></b> The use of a running virtual train to provide plausible movement is particularly distinguished from vestibular physiotherapy applications with first a fixed visual support partially obscuring the optical flow. This visual aid coupled with the attention dedicated to the task inhibits the effect of the moving environment on locomotion. However, the visual optical flow will potentially have an effect in people with fear of falling. Virtual reality shows great potential for the simulation of realistic environments for the assessment of the risk of falls and opens up avenues for the development of tests.

Immersive virtual reality makes possible to perceive and interact in a standardized, reproductible and digital environment, with a wide range of simulated situations possibilities. This study aimed to measure the potential effect of virtual reality on time and number of steps when performing a locomotor task, in a young adult’s population. Sixty young adults (32W, 28M, mean age 21.55 ± 1.32), who had their first immersive virtual reality experience, performed a locomotor task based on "Timed Up and Go" (TUG) task in real, in virtual reality in a stopped train and in virtual reality in a moving train. Time and number of steps variables representing primary locomotion indicators were measured and compared between each condition. Results showed significant increases in time and number of steps in the two virtual reality conditions compared to real but not between the two virtual reality conditions. There was an effect of virtual reality in young adults when performing the locomotor task. It means that technological and digital characteristics of the immersive virtual reality experience led to modify motor strategies employed. Adding a plausible visual optic flow did not appear to affect motor control further when the information is negligible and not essential for performing the task.

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La chute est la première cause d'accident chez les personnes âgées. Chaque année, elle concerne 1 personne sur 4 chez les plus de 65 ans. Le risque de chute est multifactoriel : ses causes peuvent notamment être motrices, attentionnelles ou cognitives. Afin de mieux caractériser, comprendre et prédire ce risque de chute, nous proposons aux praticiens une solution technologique fondée sur la réalité virtuelle, permettant de collecter et d'identifier différents indicateurs du risque de chute. Cette solution simple d'utilisation automatise le protocole expérimental et la collecte d'indicateurs, assure la reproductibilité des conditions expérimentales, et immerge le patient dans un environnement réaliste et des situations de la vie courante.Notre outil, compatible avec des dispositifs de réalité virtuelle grand public, utilise un total de 6 capteurs portés par le patient pour permettre une capture cinématique du corps complet, restitué en temps réel au patient sous la forme d'un avatar virtuel. Ces données cinématiques, rejouable pour le praticien, permettent d'alimenter un processus d'apprentissage numérique.L'expérimentation place le patient dans 6 situations de test, introduisant progressivement différentes tâches et obstacles afin de tester et de collecter des indicateurs sur ses capacités motrices, attentionnelles et cognitives, permettant des comparaisons interpatient et inter-condition.