Plantar force characteristics during walking in older adults with pronated feet: A study using a three-sensor in-shoe system

Foot pronation is common in older adults and may be associated with altered plantar loading patterns during walking. This study aimed to investigate the impact of foot pronation on regional plantar force characteristics in community-dwelling older adults. Eighty-seven participants aged ≥65 years were classified into a pronated foot group ( n = 36) or a control group ( n = 51) based on Foot Posture Index-6 (FPI-6) scores. Plantar forces were measured during overground walking using loadsol® in-shoe sensors. Peak force (PF) and impulse were calculated for the forefoot, midfoot, and rearfoot regions. Between-group comparisons were conducted using analysis of covariance adjusted for age, sex, body mass index, and walking speed, and correlations between FPI-6 scores and plantar force variables were assessed. Compared with controls, the pronated foot group showed significantly higher midfoot PF and impulse and lower forefoot PF and impulse. FPI-6 scores were positively correlated with midfoot PF and impulse. Older adults with pronated feet exhibited altered regional plantar force profiles characterized primarily by increased midfoot loading. These findings suggest that meaningful differences in plantar loading patterns associated with foot posture may be detectable using a simplified wearable insole system despite reduced sensing resolution.