Effect Of Different Standing States And Visual Interference On Standing Stability

Objective This study intends to analyze the effects of different standing states and visual interference on standing stability,and the factors affecting standing stability;to examine the test-retest reliability and effectiveness of the DE-A body balance detection system.Methods One hundred and forty-five healthy subjects were recruited from a tertiary hospital in Beijing and divided into three groups according to age,including 47 subjects in the youth group(18-44 years old),45 subjects in the middle-aged group(45-59 years old)and 53 subjects in the elderly group(60-80 years old).After basic information was collected.The acceleration RMS data were collected by inertial sensor during different standing states and visual interference,including standing still with eyes opened and closed on both feet in a horizontal plane,standing still with eyes opened and closed on both feet in a forward inclined plane,standing still with eyes opened and closed on both feet in a backward inclined plane,standing with eyes opened and closed on DE-A platform with dynamic forward inclined stress and standing with eyes opened and closed on DE-A platform with dynamic backward inclined stress.The lower limb Y balance test(YBT),the "stand walk" timing test(TUG)and the visual function index VF-7 questionnaire were tested at the same time.At an interval of 2 weeks,30 subjects were selected for acceleration RMS retest.Results(1)The acceleration RMS values of stationary stance on the backward inclined plane were greater than those of stationary stance on the flat ground(p < 0.05)and the forward inclined plane(p < 0.05,p < 0.01),and the acceleration RMS values of the dynamic backward inclined stance were greater than those of stationary stance on the flat ground(p < 0.05);(2)There was no difference in acceleration RMS values between Eyes opened and closed during the different stance states(p > 0.05);(3)Age and gender were significant factors affecting standing stability(p < 0.05,p < 0.01),BMI and exercise habits also had an effect on stability(p < 0.05),but history of falls and sports injuries had no significant effect on standing stability(P > 0.05);(4)Acceleration RMS gradually increased with age,with significantly higher acceleration RMS values in the older group than in the younger group(p < 0.05,p < 0.01),and some acceleration RMS values in the middle-aged group were significantly higher than those in the younger group(p < 0.05).The acceleration RMS values in the AP direction were higher in middle-aged and older women than those in middle-aged and older men(p <0.05,p < 0.01);(5)The acceleration RMS values detected by the inertial sensors used in this study had good test-retest reliability(ICC=0.741-0.892)and were significantly correlated with YBT,TUG and VF-7(p< 0.05,p < 0.01).Conclusion(1)Stability during static and dynamic backward leaning stance is worse than that during flat ground stance;stability in backward leaning stance is worse than that in forward leaning stance;there is no significant difference in stance stability between dynamic forward stance and dynamic backward leaning stance.(2)The acceleration RMS detected by inertial sensor is not sensitive to the changes in standing stability during eyes opened and closed.(3)Age and gender are important factors affecting standing stability,and their influence is greater than that of BMI and exercise habits;Acceleration RMS gradually increase with age,and it may be better in men than in women.(4)The acceleration RMS detected by the posture sensor of the DE-A body balance detection system has good test-retest reliability,and has significant correlation with the balance function test.