People with multiple sclerosis (MS) often have a greatly increased risk of falling and injuring themselves even when they feel they’re able to walk normally. Now a team led by scientists from The University of North Carolina (UNC) Chapel Hill School of Medicine has demonstrated what could be a relatively easy method for the early detection of such problems using virtual reality (VR). The study was recently published in PLoS One.
Study principal investigator Jason Franz, assistant professor in the UNC-Chapel Hill/North Carolina State Joint Department of Biomedical Engineering, and his colleagues sought to develop a test that would reveal balance and gait impairments even in people with MS who may not be aware of these problems or display them during normal walking. They employed a VR device that allows the experimental manipulation of visual perception. Their laboratory device is like a semi-circular theatre screen that study participants watch while walking on a treadmill. The VR scene depicted a hallway down which participants seemed to be walking, at the same speed that they walked on the treadmill. Sometimes side-to-side wobbles in the scene created the illusion for each participant that he or she was becoming unstable, triggering a corrective reaction that could be measured as a change in gait and foot placement. Franz’s hypothesis was that the participants who had MS with balance impairments would differ clearly from non-MS participants in these corrective reactions.
The scientists tested 14 people with MS and 14 age-matched non-MS participants. They found that there was indeed a clear difference between the groups in their reactions, but this only became clear when using the VR balance challenge. Franz and his colleagues now are adapting their system for use with consumer-grade VR headsets as a routine diagnostic tool to be used in neurologists’ clinics to detect balance impairments that would otherwise go unrecognized. They also hope to develop the VR system as a physical therapy tool to help MS patients improve their balance and thus reduce the risk of falls.