Recent evidence suggests most slip-related falls in daily life happen in diverse slipping conditions where the ground is not level, or the person is turning or changing direction. While slips that occur during straight walking on level ground and the responses to those slips are relatively well understood, very little is known about slips that occur while walking slopes or curved paths and which reactive responses are effective to prevent falls in such conditions. This limits the ability of clinicians to incorporate a diverse range of slipping experiences into fall- prevention interventions. Understanding how reactive responses and slip vulnerability depend on diverse slip conditions may guide future interventions that promote a more general fall resistance to the broader range of slips we encounter in the real environment. Thus, the objective of our research project is to determine the impact of turns and slopes on reactive movements and fall vulnerability.
The aims of this study are (1) to determine the effects of path curvature on reactive movements and slip vulnerability at different times in the gait cycle, and (2) to determine the effects of ground slope on reactive movements and slip vulnerability at difference times in the gait cycle. We hypothesize that diverse slipping conditions will change the reactive responses involving protective stepping and arm swing. In addition, we hypothesize that the distinct dynamics of turns and slopes produce maximum vulnerability to slips at different times in the gait cycle compared to slips during straight walking on level ground. To evaluate these aims, we will administer slip perturbations on slopes that vary in both magnitude and direction, on curved paths that vary in curvature, and with slip onset that varies across early, middle, and late stance. Understanding the relationships between diverse slipping conditions, reactive responses, slip severity and fall vulnerability may guide future research and training interventions towards more comprehensive fall resistance ability.
Slips cause approximate 25-40% of falls, which are the number one cause of injury, and for older adults, the number one cause of injury related death. Emerging evidence from studies in slip epidemiology indicate a majority of slips come from diverse slipping conditions, and that to improve a general fall resistance in daily life, a general ability to respond effectively to the full range of slips must be developed. Using movement analysis and state-of-the-art equipment, we will determine the relationships between diverse slip conditions, reactive responses to slips from those conditions, and slip vulnerability across the gait cycle to generate new data that may guide future interventions.
