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Published on: August 30, 2016
Local dynamic stability in turning and straight-line gait
Ava D Segal1, Michael S Orendurff, Joseph M Czerniecki
1Center of Excellence for Limb Loss Prevention and Prosthetic Engineering, Rehabilitation Research and Development, Veterans Administration Puget Sound Health Care System, Seattle, WA, USA. avasegal@gmail.com
Journal of Biomechanics
|April 15, 2008
Summary
Turning gait is less stable than straight-line walking, increasing fall risk. This study quantified turning stability using local dynamic stability (lambda) in able-bodied individuals, finding reduced stability in key joints during turns.
Area of Science:
- Biomechanics
- Gait Analysis
- Human Movement Science
Background:
- Navigating corners and obstacles presents unique challenges for ambulation.
- Turning gait may increase the risk of falls and fall-related injuries.
- Quantifying turning stability can identify individuals at higher risk of falling.
Purpose of the Study:
- To determine if local dynamic stability during constant speed turning is reduced compared to straight-line walking.
- To assess the efficacy of therapeutic interventions for mobility-impaired populations by comparing turning stability.
Main Methods:
- Employed Maximum finite-time Lyapunov exponents (lambda) to estimate local dynamic stability.
- Analyzed sagittal plane hip, knee, and ankle trajectories in 19 able-bodied subjects.
- Compared turning gait stability to straight-line treadmill walking at two speeds.
Main Results:
- Turning lambda was significantly greater than straight lambda for the hip, right knee, and ankle (p<0.05).
- Left knee angle stability during turning was similar to straight-line walking.
- No significant differences in stability were found between left and right limbs or inside/outside limbs during turning.
Conclusions:
- Able-bodied individuals exhibit reduced local dynamic stability in hip, right knee, and ankle kinematics during turning compared to straight-line walking.
- These findings suggest that turning stability metrics can serve as a comparative tool for evaluating interventions aimed at improving mobility.
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