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Evaluating Postural Control and Lower-extremity Muscle Activation in Individuals with Chronic Ankle Instability
Published on: September 18, 2020
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Nonlinear Dynamic Measures for Evaluating Postural Control in Individuals With and Without Chronic Ankle Instability.
Masafumi Terada1, Megan Beard2, Sara Carey3
11 Ritsumeikan University.
Motor Control
|October 16, 2018
Summary
Individuals with chronic ankle instability (CAI) show reduced time-to-boundary during single-leg balance, indicating impaired sensorimotor control. Sample entropy did not differ between groups, suggesting balance regularity remains intact despite instability.
Area of Science:
- Biomechanics
- Motor Control
- Sports Medicine
Background:
- Chronic ankle instability (CAI) is a common condition following lateral ankle sprains.
- Impaired sensorimotor control is often associated with CAI, affecting balance.
- Understanding balance deficits is crucial for effective rehabilitation strategies.
Purpose of the Study:
- To compare time-to-boundary and sample entropy during a single-leg balance task.
- To evaluate these measures in individuals with CAI, lateral ankle sprain copers, and healthy controls.
Main Methods:
- Single-leg balance task performed under eyes-closed conditions.
- Involved 22 participants with CAI, 20 copers, and 24 healthy controls.
- Analysis of time-to-boundary and sample entropy of center of pressure data.
Main Results:
- Participants with CAI exhibited significantly lower time-to-boundary values compared to copers and controls.
- No significant differences in sample entropy were found between the three groups.
- Lower time-to-boundary suggests a constrained sensorimotor system in individuals with CAI.
Conclusions:
- Chronic ankle instability may limit the ability to maintain center of pressure within the base of support.
- The regularity of center of pressure velocity appears unaffected in individuals with CAI during this task.
- Time-to-boundary may be a more sensitive indicator of balance deficits in CAI than sample entropy.
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