Differences in Postural Control During Single-Leg Stance Among Healthy Individuals With Different Foot Types

OBJECTIVE: To identify differences in postural control among healthy individuals with different architectural foot types. DESIGN AND SETTING: We compared postural control during single-leg stance in healthy individuals with cavus, rectus, and planus foot types in our athletic training research laboratory. SUBJECTS: Thirty healthy, young adults (15 men, 15 women; age, 21.9 +/- 2.0 years; mass, 71.6 +/- 16.7 kg; height, 168.4 +/- 13.6 cm) had their feet categorized based on rearfoot and forefoot alignment measures. The right and left feet of a subject could be classified into different categories, and each foot was treated as a subject. There were 19 cavus, 23 rectus, and 18 planus feet. MEASUREMENTS: Subjects performed three 10-second trials of single-leg stance on each leg with eyes open while standing on a force platform. Dependent measures were center-of-pressure (COP) excursion area and velocity. RESULTS: Subjects with cavus feet used significantly larger COP excursion areas than did subjects with rectus feet. However, COP excursion velocities were not significantly different among foot types. CONCLUSIONS: Clinicians and researchers assessing postural control in single-leg stance with measures of COP excursion area must be cognizant of preexisting differences among foot types. If individuals' foot types are not taken into account, the results of clinical and research investigations assessing COP excursion area after injury may be confounded.