Does foot placement affect the reliability of static foot posture measurements?

Background: Previous studies have reported conflicting results on whether different foot placements in standing can affect static measurements of foot posture. We sought to determine whether three measurements of static foot posture could be consistently measured in three different foot placements while standing.

Methods: Twenty individuals, 12 women and eight men, with a mean age of 24.8 years consented to participate. Two raters assessed the dorsal arch height, midfoot width, and heel width of each foot while the participant stood in the following three foot placements: a standardized placement, a participant-determined placement after marching in place, and a rater-determined foot placement based on observation of the participant's angle of gait and base of support while walking.

Results: All three measurements of static foot posture were shown to have high levels of intrarater and interrater reliability. Significant differences in the measurements of dorsal arch height, midfoot width, and heel width were found among all three of the foot placements. There were no differences between the two raters for any of the three measurements of foot posture.

Conclusions: Based on these findings, we recommend that clinicians perform measurements of static foot posture using the same standing foot placement between sessions to ensure a high level of measurement consistency.