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Differences in geriatric anthropometric data between DXA-based subject-specific estimates and non-age-specific
April J Chambers1, Alison L Sukits, Jean L McCrory
1Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA.
Journal of Applied Biomechanics
|August 17, 2011
Summary
This study reveals significant differences in body segment parameters between dual-energy x-ray absorptiometry (DXA) and traditional regression models in older adults. Age, obesity, and gender impact these anthropometric predictions, highlighting the need for tailored geriatric models.
Area of Science:
- Geriatric medicine
- Biomechanics
- Anthropometry
Background:
- Aging, obesity, and gender significantly influence adult anthropometrics.
- Accurate body segment parameters are crucial for biomechanical analysis and clinical applications in older adults.
Purpose of the Study:
- To compare body segment parameters derived from a dual-energy x-ray absorptiometry (DXA) subject-specific method versus traditional regression models.
- To examine the impact of aging, gender, and obesity on the discrepancies between these two anthropometric measurement methods.
Main Methods:
- Eighty-three healthy older adults participated.
- Whole-body DXA scans were used to determine segment mass, length, center of mass, and radius of gyration.
- Traditional regression models (de Leva, 1996) were employed for comparative parameter estimation.
Main Results:
- Method type significantly impacted most body segment parameters, excluding forearm segment mass.
- Observed differences related to obesity and gender indicate potential inaccuracies when using traditional regressions in the aging population.
Conclusions:
- Traditional regression models may not accurately predict body segment parameters in older adults.
- Future regression models should incorporate age, gender, and obesity to improve anthropometric accuracy in the geriatric population.
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