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12:18
An Instrumented Pull Test to Characterize Postural Responses
Published on: April 6, 2019
Wrist postures and forces in tree planters during three tree unloading conditions
Kathleen Denbeigh1, Tegan R Slot, Geneviève A Dumas
1a Department of Mechanical and Materials Engineering , Queen's University , Kingston , Canada.
Ergonomics
|August 15, 2013
Summary
Tree planters experience significant wrist extension and high forces during shoveling, increasing risks for musculoskeletal pain and repetitive strain injuries like carpal tunnel syndrome. Unloading techniques did not alter these risks.
Area of Science:
- Occupational Health
- Ergonomics
- Musculoskeletal Disorders
Background:
- Wrist pain is a common complaint among tree planters.
- Repetitive strain injuries (RSIs) and musculoskeletal pain are prevalent in manual labor occupations.
- Understanding biomechanical factors during tree planting is crucial for injury prevention.
Purpose of the Study:
- To investigate wrist postures and forces during tree planting using a shovel.
- To determine if different tree unloading techniques affect wrist biomechanics.
- To identify potential risk factors for musculoskeletal pain and RSIs in tree planters.
Main Methods:
- Experienced tree planters performed simulated tree planting in a laboratory.
- Three unloading conditions were tested: symmetric, right-loaded, and left-loaded planting bags.
- An optoelectric system captured wrist posture, and a strain-gauged shovel measured forces at the wrist.
Main Results:
- Observed wrist extension reached up to 45°, combined with wrist deviation.
- Average resultant forces at the wrist were consistently high (over 30 N).
- No significant differences in wrist posture or forces were found between the different unloading conditions.
Conclusions:
- Extreme wrist extension and deviation postures are potential risk factors for musculoskeletal pain.
- Sustained high forces at the wrist increase the risk of developing RSIs, including carpal tunnel syndrome.
- Current tree unloading techniques do not mitigate the identified biomechanical risks.
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