Stability Measures to Compare Fallers and Non-Fallers During Locomotion
Advisor Information
Brian A Knarr
Location
Omaha, NE
Presentation Type
Poster
Start Date
1-3-2019 12:30 PM
End Date
1-3-2019 1:45 PM
Abstract
Falls represent a critical health issue for the elderly community as it causes injury, disability, and even death. Thus, maintaining postural stability during locomotion is essential to perform activity of daily living safely and efficiently. Variability measures have been used to assess stability in different environments only for young healthy, or between fallers and non-fallers during static balance but not during locomotion. Despite the promising literature, limited research has investigated the effects of stability measures on identifying fallers safely within different environments. Therefore, the purpose of this study was to assess the sensitivity of outside motion measures relative to the in-lab motion measures using different stability assessments in elderly with history of falls. Four participants with a history of falling and six age-matched community dwelling participants were recruited. Participants performed a 6-minute treadmill walk test indoors, and a 3-minute walk test on paved surface outdoors during self-selected (SS) speed. A split-belt treadmill (Bertec) and motion capture system (16 camera Vicon) were used to collect biomechanical data indoors. An IMU-based system (Xsens,) was used to collect biomechanical data indoors and outdoors. Two methods were used to assess stability. A/P and M/L Margin of Stability (MOS)6 at heel strike for each limb were used to analyze motion capture data. Means and minimums were included. Lyapunov exponents (LyE)7 of M/L pelvis sway and pelvis acceleration, for motion capture and accelerometer data respectively, were used as a measure of gait stability. Independent t-test was used to measure the difference in stability measures between fallers and non-fallers groups. Only LyE of M/L pelvis sway captured using motion capture during indoor walking trials showed significant differences between fallers and non-fallers. Our main finding indicates LyE of ML pelvis sway using motion capture may be the best method to indicate elderly with a history of falls during indoor self-selected gait, which could be due to its ability to measure variability of pelvis sway on a wider scale using a more precise measure of motion. From our initial findings, accelerometer data was unable to differentiate between fallers and non-fallers during both indoor and outdoor trials.
Stability Measures to Compare Fallers and Non-Fallers During Locomotion
Omaha, NE
Falls represent a critical health issue for the elderly community as it causes injury, disability, and even death. Thus, maintaining postural stability during locomotion is essential to perform activity of daily living safely and efficiently. Variability measures have been used to assess stability in different environments only for young healthy, or between fallers and non-fallers during static balance but not during locomotion. Despite the promising literature, limited research has investigated the effects of stability measures on identifying fallers safely within different environments. Therefore, the purpose of this study was to assess the sensitivity of outside motion measures relative to the in-lab motion measures using different stability assessments in elderly with history of falls. Four participants with a history of falling and six age-matched community dwelling participants were recruited. Participants performed a 6-minute treadmill walk test indoors, and a 3-minute walk test on paved surface outdoors during self-selected (SS) speed. A split-belt treadmill (Bertec) and motion capture system (16 camera Vicon) were used to collect biomechanical data indoors. An IMU-based system (Xsens,) was used to collect biomechanical data indoors and outdoors. Two methods were used to assess stability. A/P and M/L Margin of Stability (MOS)6 at heel strike for each limb were used to analyze motion capture data. Means and minimums were included. Lyapunov exponents (LyE)7 of M/L pelvis sway and pelvis acceleration, for motion capture and accelerometer data respectively, were used as a measure of gait stability. Independent t-test was used to measure the difference in stability measures between fallers and non-fallers groups. Only LyE of M/L pelvis sway captured using motion capture during indoor walking trials showed significant differences between fallers and non-fallers. Our main finding indicates LyE of ML pelvis sway using motion capture may be the best method to indicate elderly with a history of falls during indoor self-selected gait, which could be due to its ability to measure variability of pelvis sway on a wider scale using a more precise measure of motion. From our initial findings, accelerometer data was unable to differentiate between fallers and non-fallers during both indoor and outdoor trials.