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Hand-hold location and trunk kinematics during box handling
1The Ergonomics Laboratory, Department of Industrial and Manufacturing Systems Engineering, Iowa State University, Ames, IA 50011-2164, USA.
Ergonomics
|July 27, 2010
Summary
Hand placement significantly impacts trunk kinematics during lifting tasks, influencing low back injury risk. Asymmetric grips and heavier loads increased the probability of high-risk lifting postures.
Area of Science:
- Occupational Biomechanics
- Ergonomics
- Injury Prevention
Background:
- Trunk kinematics are linked to low back injury risk during lifting.
- Hand-hold positions may alter trunk movements and associated risks.
Purpose of the Study:
- To investigate how different hand placement locations affect trunk kinematics.
- To determine the influence of hand placement on the probability of high-risk lifting.
Main Methods:
- Fourteen subjects performed lifting tasks with varying box weights (5 or 10 kg) and hand placements (symmetric and asymmetric).
- Trunk kinematics (position, velocity, acceleration) were measured using the lumbar motion monitor (LMM).
- Probability of High Risk Group Membership (PHRGM) was calculated using LMM risk assessment model.
Main Results:
- Significant effects of hand placement on trunk kinematics were observed.
- PHRGM varied significantly, from 20% (symmetric, low load) to 38% (asymmetric, 10 kg).
Conclusions:
- Hand placement is a critical factor influencing trunk kinematics during lifting.
- Altering hand-hold positions can modify lifting biomechanics and associated injury risk profiles.
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