The Relationship Between Ambulatory Activity Patterns and Gait Kinematic Variability
Advisor Information
Sara Myers
Location
Milo Bail Student Center Ballroom
Presentation Type
Poster
Start Date
8-3-2013 1:00 PM
End Date
8-3-2013 4:00 PM
Abstract
The purpose of this study is to investigate the relationship between ambulatory activity as measured through an accelerometer and gait kinematic variability as measured through 3-D motion capture. Analysis of gait variability can provide insights in the motor control of the movement. However, current scientific methods for assessing gait variability are limited to a laboratory. An accelerometer is a tool that may be used to provide similar insight into gait variability. Seven healthy young adults were asked to walk on a treadmill while wearing an accelerometer at the hip. Subjects walked at a slow self-selected speed followed by a fast self-selected speed. Continuous joint angle time series were calculated at the ankle, knee, and hip. Raw acceleration was analyzed from the accelerometer. Measures of the temporal structure of variability included the Lyapunov Exponent (LyE) and approximate entropy (ApEn). Pearson’s correlations were used to calculate the relationship between gait kinematics and acceleration. There was a significant, positive relationship at the LyE of the hip during the slow condition. There were several moderate but non-significant correlations for LyE at the ankle during slow speed and for ApEn at the knee during slow speed and at the ankle and knee during fast speed. These results provide evidence that there is a relationship between variability of ambulatory activity and gait kinematic variability, however the sample size may be too low to reveal strong correlations. Furthermore, the hip may show the strongest correlation due to the fact that the accelerometer was placed at the hip.
The Relationship Between Ambulatory Activity Patterns and Gait Kinematic Variability
Milo Bail Student Center Ballroom
The purpose of this study is to investigate the relationship between ambulatory activity as measured through an accelerometer and gait kinematic variability as measured through 3-D motion capture. Analysis of gait variability can provide insights in the motor control of the movement. However, current scientific methods for assessing gait variability are limited to a laboratory. An accelerometer is a tool that may be used to provide similar insight into gait variability. Seven healthy young adults were asked to walk on a treadmill while wearing an accelerometer at the hip. Subjects walked at a slow self-selected speed followed by a fast self-selected speed. Continuous joint angle time series were calculated at the ankle, knee, and hip. Raw acceleration was analyzed from the accelerometer. Measures of the temporal structure of variability included the Lyapunov Exponent (LyE) and approximate entropy (ApEn). Pearson’s correlations were used to calculate the relationship between gait kinematics and acceleration. There was a significant, positive relationship at the LyE of the hip during the slow condition. There were several moderate but non-significant correlations for LyE at the ankle during slow speed and for ApEn at the knee during slow speed and at the ankle and knee during fast speed. These results provide evidence that there is a relationship between variability of ambulatory activity and gait kinematic variability, however the sample size may be too low to reveal strong correlations. Furthermore, the hip may show the strongest correlation due to the fact that the accelerometer was placed at the hip.