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Multi-segment trunk kinematics during a loaded lifting task for elderly and young subjects.
R J Burgess1, S Hillier, D Keogh
1Huggins Hospital, Wolfeboro, NH, USA.
Ergonomics
|March 20, 2009
Summary
Elderly individuals exhibit altered trunk motion during lifting tasks, with increased displacement and reduced range of motion in key segments. This segmental trunk kinematics difference may increase their risk of injury and falls.
Area of Science:
- Biomechanics
- Human Movement Science
- Gerontology
Background:
- Manual handling often simplifies trunk motion to a single segment, overlooking multi-segmental contributions.
- Understanding age-related changes in trunk kinematics is crucial for injury prevention during lifting tasks.
Purpose of the Study:
- To compare segmental trunk motion between young and elderly populations during a standardized lifting task.
- To investigate the influence of stance conditions on trunk kinematics in different age groups.
Main Methods:
- Twelve elderly and 19 young subjects performed repeated lifting of a 5 kg box.
- Electromagnetic tracking system recorded displacement and angular kinematics of trunk segments (pelvis, lumbar, thorax).
Main Results:
- Elderly subjects showed significantly greater pelvic and trunk displacement.
- Elderly subjects exhibited significantly reduced range of motion in the pelvis and lower thorax (T10-L1).
- Upper thorax (C7-T10) motion was sometimes greater than lumbar motion and contrasted with lower segment movements.
Conclusions:
- Decreased segmental trunk angular kinematics in the elderly may lead to increased displacement, heightening the risk of injury and falls.
- Multi-segmental analysis of trunk mechanics is essential, revealing unique contributions of the pelvis, lumbar spine, and thorax segments.
- Reduced pelvic and lower thoracic angular motion in the elderly contributes to increased displacement kinematics, elevating fall risk compared to younger individuals.
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