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Published on: June 16, 2021
The Association Between Forceful Hand Exertions and Musculoskeletal Disorders of the Neck and Shoulder: A Prospective
Alexa Zimbalist1, David Rempel, Lydia Feng
1From the University of California Berkeley, Berkeley, California (Mss Zimbalist and Feng, Dr Harris-Adamson); University of California San Francisco, San Francisco, California (Dr Rempel).
Objective:
The aim of this study was to estimate associations between biomechanical exposures and workplace neck and shoulder musculoskeletal disorders (NSMSDs) in a prospective cohort.
Methods:
Manufacturing workers (N = 349) were followed for 28 months. Biomechanical exposures were collected on each individual, and physical examinations were performed every 4 months. Prevalent cases at baseline (n = 30) were excluded from the analysis.
Results:
There were 18 incident cases of NSMSDs. Greater than 33% time in forceful hand exertion doubled the rate of incident NSMSDs. Greater than 18 degrees of shoulder abduction, during forceful hand exertion, increased the rate by 55%. Confidence intervals were wide.
Conclusions:
Effect estimates of the relationship between forceful hand exertions and NSMSDs were consistently elevated whether measured in isolation or while in shoulder abduction. Following a larger cohort with more frequent physical examinations would improve estimates of the model.
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