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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
Nonlinear analysis of sitting postural sway indicates developmental delay in infants
Joan E Deffeyes1, Regina T Harbourne, Anastasia Kyvelidou
1Biomechanics Laboratory, University of Nebraska at Omaha, Omaha, NE, USA.
Clinical Biomechanics (Bristol, Avon)
|June 5, 2009
Summary
The largest Lyapunov exponent, a nonlinear measure of postural sway, effectively differentiates typical infant development from delayed development, including those with cerebral palsy risks. This finding aids in identifying developmental delays and assessing therapeutic interventions.
Area of Science:
- Developmental Pediatrics
- Motor Control Science
- Biomechanical Analysis
Background:
- Upright sitting is a key infant motor milestone.
- Sitting postural sway reflects developing motor control.
- Optimal measures for assessing infant postural sway are not well-established.
Purpose of the Study:
- To identify optimal measures of sitting postural sway for infant development.
- To differentiate between typically developing infants and those with delayed development or cerebral palsy risks.
Main Methods:
- Collected sitting postural sway data from 33 typically developing infants and 26 infants with delayed development (or at risk for cerebral palsy).
- Infants were tested at the point of maintaining sitting for approximately 10 seconds.
- Analyzed center of pressure data using linear and nonlinear measures from force platform recordings.
Main Results:
- The largest Lyapunov exponent, a nonlinear measure, was the sole significant differentiator between the two infant groups.
- Typically developing infants exhibited a higher largest Lyapunov exponent, suggesting less repetitive movement patterns.
Conclusions:
- Nonlinear measures like the largest Lyapunov exponent show promise for identifying developmental pathology in infants.
- This measure could serve as a valuable tool for evaluating the efficacy of therapeutic interventions in infant motor development.
