Determination of the minimum number of steps for assessment of plantar pressure in gait of children, adults and older adults

BACKGROUND: Plantar pressure provides useful information for the study of locomotion. Such measure is often conducted based on average of different number of steps. Previous studies are not clear regarding the minimum number of observations to reduce group variability in determination of peak pressures, especially when comparing people in different age groups. AIM: To determine the minimum number of steps required to determine peak pressure in different regions of the foot during the gait of people from different age groups. METHODS: Children (n=12), adults (n=13) and older adults (n=12) underwent measurements of plantar pressure using a Matscan pressure mapping system for two days, while walking barefoot at their preferred gait speed. Peak pressure was determined for 10 steps in each of the days of assessment and analyzed considering foot regions of rearfoot, midfoot and forefoot. Peak pressure variability was determined considering data from two to ten steps. RESULTS: Four steps measurements showed the lower variability in peak pressure in participants from different age groups. Although variability in rearfoot showed to be higher, the minimal number of steps we determined was useful to determine peak pressure across the different regions of the foot. INTERPRETATION: The determination of peak pressure in assessment of gait in able bodied participants from different age groups can consider data recorded from four steps.