Avoiding trip- and slip-hazards in suburban footpaths by older adults: an immersive virtual reality experiment

BACKGROUND: Older people often fall due to trips and slips in daily life. This study aimed to elucidate the mechanisms of trip- and slip-hazard avoidance while walking through an immersive virtual reality suburban footpath. METHODS: Forty-six participants (71.8 ± 4.7 [65-84] years) wore an immersive head-mounted display (Oculus Rift S) and safety harness while walking on a split-belt treadmill (M-Gait). Participants walked on a virtual footpath while avoiding hazards including raised concrete slabs (trips) and puddles (slips) and as a secondary task collected apples. Foot-hazard contacts resulted in treadmill belt accelerations/decelerations to evoke balance loss. Hazard contact rates and gait kinematics were measured using Vicon motion capture. RESULTS: Participants contacted more trip-hazards (63.1%) than slip-hazards (22.2%; p <.001). Trip-hazards were more frequently collided with by the trailing foot (56.9%) compared to the leading foot (16.7%; p <.001). Trailing foot contact with both trip- and slip-hazards resulted in significant changes in extrapolated Centre of Mass (XCoM) and Margin of Stability (MoS) (p <.05). Following trailing foot contacting trip-hazards, participants compensated effectively by increasing MoS, whereas contacting slip-hazards reduced MoS, indicating a higher risk of losing balance. CONCLUSION: On a virtual suburban footpath, older adults often collided with trip-hazards with their trailing foot, which was typically beyond their visual field, while slip-hazards more commonly involved the leading foot. These insights can support the development of fall prevention programs that better mirror everyday walking challenges.