Development of Lumbar Stability Index (LSI) Using Motion Sensor According to Age

The total number of subjects initially aimed for in this study was 60 but due to the disruption in data collection, the data from 3 subjects were omitted, and a total of 57 control subjects were used for data analysis. As the main outcome measure, a consistent average movement pattern in healthy subjects during the wall plank-and-roll test was verified. In this axial rotation axis, there were 2 types of movements, whereas in the kyphosis lordosis axis, 98.2% of the subjects showed one movement pattern, and in the lateral bending axis, 94.7% of the subjets showed one movement pattern. When the subjects were stratified based on age to 20-42 year old group and 51-79 year old group, statistically significant differences were observed in the axial rotation axis and in the kyphosis lordosis axis. In the axial rotation axis, the 20-42 year old group showed 2 representative movement patterns (40:60), and in the 51-79 year old group, most subjects showed a single pattern (8:60), yielding a P-value<0.05 using the chi-square test. In the kyphosis lordosis axis the two age groups had a difference in offset throughout the wall plank-and-roll test, which was verified using the Wilcoxon rank sum test yielding a P-value=0.03.