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Updated: Jul 13, 2026
07:52
Evaluating Postural Control and Lower-extremity Muscle Activation in Individuals with Chronic Ankle Instability
Published on: September 18, 2020
The relation between postural stability and weight distribution in healthy subjects
Linda C Anker1, Vivian Weerdesteyn, Ilse J W van Nes
1Sint Maartenskliniek Research, Development and Education, Nijmegen, The Netherlands.
Gait & Posture
|July 24, 2007
Summary
Altering leg weight distribution significantly impacts balance control during standing. Increased weight-bearing asymmetry amplifies postural sway and control asymmetry, particularly in the lateral direction.
Area of Science:
- Biomechanics
- Human postural control
- Motor control
Background:
- Understanding leg-loading asymmetry effects on postural control is crucial for patients with lateralized disorders.
- Assessing postural control and asymmetry in healthy individuals provides a baseline for clinical comparisons.
Purpose of the Study:
- To investigate the relationship between weight-bearing asymmetry (WBA) and postural control and control asymmetry during quiet upright standing.
- To quantify how varying degrees of WBA affect center of pressure (CP) fluctuations.
Main Methods:
- Utilized a dual-plate force platform for posturographic assessment.
- Healthy young and middle-aged participants stood with controlled WBA (0-30% extra body weight on one leg).
- Measured CP fluctuations in lateral (LAT) and anterior-posterior (AP) directions under both feet individually and together.
Main Results:
- Increased WBA led to greater overall postural sway velocity, primarily in the LAT direction.
- Postural control asymmetry increased with WBA, favoring the more loaded leg in both LAT and AP directions.
- First-order polynomial functions best described the relationship between WBA and sway velocity asymmetry.
Conclusions:
- Weight-bearing asymmetry alters biomechanical constraints, increasing postural instability.
- Increased WBA may reduce hip load/unload mechanism efficiency and increase compensatory ankle moments.
- Findings provide insights into postural adjustments necessitated by uneven leg loading.
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