A systematic review of the effect of ageing and falls history on minimum foot clearance characteristics during level walking

Minimum foot clearance (MFC) is the minimum vertical distance between the lowest point of the foot of the swing leg and the walking surface during the swing phase of the gait cycle. MFC is a gait variable that is linked to the mechanism of a trip because reduced MFC for a given step during walking increases the susceptibility to tripping on an unseen obstacle or due to undetected changes in surface height. Given that tripping is a common cause of falls in older persons, this review was undertaken to determine whether ageing and/or history of falls in older adults influences MFC characteristics during level walking. Studies that assessed MFC characteristics including measures of central tendency (mean and/or median), variability (linear and non-linear measures) and shape (skewness, kurtosis) of the MFC distribution were included in the review. The final yield from a search of seven electronic research databases was 12 unique articles that met all the inclusion criteria. Ageing does not appear to alter measures of central tendency or shape of the MFC distribution. However greater MFC variability was observed in older compared to younger adults and older fallers compared to older non-fallers in the majority of studies. Greater MFC variability may contribute to increased risk of trips and associated falls in older compared to young adults and older fallers compared to older non-fallers.