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12:18
An Instrumented Pull Test to Characterize Postural Responses
Published on: April 6, 2019
Shoulder disorders and postural stress in automobile assembly work
L Punnett1, L J Fine, W M Keyserling
1Center for Ergonomics, The University of Michigan, Ann Arbor, Michigan, United States. Laura_Punnett@UML.EDU
Scandinavian Journal of Work, Environment & Health
|September 20, 2000
Summary
Severe shoulder flexion or abduction in nonneutral postures is linked to increased risk of shoulder disorders. This risk escalates with longer exposure durations during the work cycle, impacting both left and right shoulders.
Area of Science:
- Occupational Health
- Ergonomics
- Musculoskeletal Disorders
Background:
- Nonneutral postures are common in manual labor and may contribute to shoulder disorders.
- Evaluating the specific risks associated with shoulder postures in an industrial setting is crucial for prevention.
Purpose of the Study:
- To investigate the association between nonneutral shoulder postures and the risk of developing shoulder disorders.
- To quantify the risk related to specific shoulder flexion and abduction angles and exposure durations.
Main Methods:
- A case-referent study was conducted in an automobile assembly plant.
- Cases were workers with shoulder pain; referents were workers without shoulder disorders.
- Job analyses assessed postural and biomechanical demands for 79 cases and 124 referents.
Main Results:
- Severe shoulder flexion or abduction (above 90 degrees) was prevalent, affecting 41% of the right arm and 35% of the left arm.
- Shoulder disorders were significantly associated with severe left arm (OR 3.2) and right arm (OR 2.3) flexion/abduction.
- Risk increased with the proportion of the work cycle involving these postures; hand-held tool use also increased risk.
Conclusions:
- Severe shoulder flexion or abduction, particularly when exceeding 10% of the work cycle, predicts chronic or recurrent shoulder disorders.
- Findings highlight the importance of addressing nonneutral shoulder postures in occupational settings to mitigate disorder risk.
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