Effect of Foot Position on Postural Balance Assessment Using Center of Pressure Parameters During the Romberg Test

The Romberg test is widely used for static postural balance assessment, but the effect of foot position on center of pressure (CoP) parameters remains unclear. This study compared CoP parameters in 47 participants aged 13 to 71 years, with two foot positions: a comfortable stance and feet together. This broad age range was used to capture significant diversity in physical development, balance, and health conditions, ensuring results representative of variability in a general population. Participants performed the test with eyes open (EO) and closed (EC). CoP parameters such as mean velocity, range, standard deviation, area of the 95% confidence ellipse, mean frequency, and Romberg ratio were measured. Paired t-tests were used to evaluate the effect of vision and foot position. The results showed that both vision and foot position significantly influenced postural stability, with greater sway in the EC and feet together conditions, especially in the mediolateral direction. For example, mean velocity increased from 10.02 ± 4.09 mm/s in EO-comfortable stance to 21.75 ± 8.93 mm/s in EC-feet together. These findings highlight the importance of standardizing foot position and considering the effect of vision when assessing postural stability.