Gait instability in community-dwelling older fallers : how visual search behaviors reveal hidden fall risk

Abstract

Introduction: Falls during walking contribute significantly to injuries in older adults, with gait instability being a key risk factor. While visual search behaviors are essential for safe navigation, their relationship to instability remains unclear. This study compared visual search behaviors during walking between community-dwelling older adults with and without a fall history and examined their association with gait instability. Methods: Seventy-four older adults (mean age: 70.7 ± 3.9 years; 37 fallers, 37 non-fallers) walked at a self-selected pace along an 8-m level-ground walkway for five trials. Gait stability was assessed by variability of spatial and temporal gait parameters, where greater variability reflects reduced stability. Visual search behaviors were assessed by the percentage of total fixations and the percentage of total fixation duration directed towards the ground (floor area of the walkway), the destination (end-point of the walkway), and random areas (non-task-relevant areas). Results: No significant differences in visual search behaviors were observed between groups. In fallers, greater variability of stride time was associated with greater percentages of the number of fixations on the ground (ρ = 0.348, p = 0.043), while greater variability of step width was associated with fewer percentages of the number of fixations (ρ = -0.464, p = 0.006) and fixation duration on the destination (ρ = -0.452, p = 0.007). These associations were not apparent in non-fallers. Conclusions: Despite similar visual search behaviors between older fallers and non-fallers, fallers exhibited unique associations between reduced visual scanning towards the destination and lateral instability (i.e., increased variability of step width) during walking—an effective predictor of falls. This suggests maladaptive visuomotor behaviors and compromised gait stability may be interrelated, collectively increasing fall injury risk in older fallers. Practical Applications: The observed associations suggest that visuomotor training could be explored in fall prevention programs to improve gait safety in older fallers. Future studies should investigate causality and evaluate efficacy in hazard-rich environments.