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Updated: May 7, 2026
08:24
Sit-to-stand-and-walk from 120% Knee Height: A Novel Approach to Assess Dynamic Postural Control Independent of Lead-limb
Published on: August 30, 2016
Development of a new approach to quantifying stepping stability using ensemble empirical mode decomposition
Xingran Cui1, Chung-Kang Peng, Madalena D Costa
1Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Gait & Posture
|October 8, 2013
Summary
A new step stability index (SSI) effectively distinguishes fall risk in older adults. Higher SSI indicates better gait stability, even during challenging obstacle navigation, aiding fall prevention strategies.
Area of Science:
- Biomechanics
- Gerontology
- Signal Processing
Background:
- Gait is a non-stationary process due to environmental interactions.
- Assessing gait stability and fall risk in older adults is crucial.
Purpose of the Study:
- Introduce a novel step stability index (SSI) for quantifying gait stability in older adults.
- Evaluate SSI's ability to differentiate fallers from non-fallers and assess fall risk.
Main Methods:
- Utilized ensemble empirical mode decomposition to develop the SSI.
- Analyzed accelerometer data from older adults (fallers and controls) during varied walking conditions.
- Measured SSI under baseline and obstacle course walking scenarios.
Main Results:
- Controls exhibited significantly higher SSI than fallers across all conditions (p ≤ 0.05).
- SSI was significantly lower during obstacle walking for both groups (p<0.0001).
- SSI correlated with established clinical measures of mobility and fall risk (r = 0.27–0.73).
Conclusions:
- The novel SSI, derived from ensemble empirical mode decomposition, shows promise in quantifying gait stability.
- SSI may serve as a valuable tool for assessing fall risk in older adults during dynamic, real-world walking conditions.
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