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Updated: Apr 19, 2026
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Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
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Difference in static and dynamic stability between flexible flatfeet and neutral feet.
Jeong-Ah Kim1, One-Bin Lim1, Chung-Hwi Yi2
1Department of Physical Therapy, The Graduate School, Yonsei University, Wonju, Republic of Korea.
Gait & Posture
|January 7, 2015
Summary
Individuals with flexible flatfeet (FF) exhibit poorer static postural stability than those with neutral feet (NF). However, dynamic stability and the relationship between static and dynamic measures did not differ between groups.
Area of Science:
- Biomechanics
- Orthopedics
- Sports Medicine
Background:
- Flexible flatfeet (FF) are associated with altered postural control.
- Secondary injuries may arise from postural instability in individuals with FF.
- Limited research exists on static versus dynamic stability differences in FF and NF populations.
Purpose of the Study:
- To compare static and dynamic postural stability between individuals with FF and NF.
- To explore the relationship between static and dynamic stability measures in these groups.
Main Methods:
- Twenty-eight participants (14 FF, 14 NF) were recruited.
- Static stability was assessed via center of pressure (COP) speed during single-leg stance (eyes open/closed).
- Dynamic stability was evaluated using the Y Balance Test (Y score).
Main Results:
- COP speed was significantly higher in the FF group compared to the NF group (both eyes open and closed conditions).
- No significant differences in Y balance test scores were found between the FF and NF groups.
- No significant correlation was observed between COP speed and Y balance test scores within either group.
Conclusions:
- Individuals with FF demonstrate impaired static postural stability relative to those with NF.
- Dynamic postural stability does not appear to differ between FF and NF groups.
- Static and dynamic postural stability may be independent in individuals with FF and NF.
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