Abstract: Objective To study the balance function of normal persons and to explore the differences in gender and age groups.Methods Forty parameters of 445 normal persons(16-70 years old, 205 of male, 240 of female ) were detected by static posturography while they were in seat, double foot standing with opening and closing eyes, and single foot standing with opening eyes. The results of male and female, standing with opening eyes and closing eyes, left foot standing and right foot standing were compared.Results Everyone's center of gravity was distributed in A zone while they were in seat. At standing with opening eyes and closing eyes, the center of gravity in A zone were in 429 subjects( 96.4%) and 436 subjects( 98.0%). Most parameters showed significant difference between the women and the men, opening eyes and closing eyes, left foot standing and right foot standing, different age groups. The stability in closing eyes was better than that in opening eyes, right foot standing was better than left foot standing. Most values of 20—39 years old group were the best, 70—79 years old group were the worst.Conclusion Static posturography can evaluate human balance function objectively and quantitatively. The stability is related to age and gender. To judge the balance function, the subject's age and sex must be taken into account.

Key words: balance function, static posturography, normal subject, stability