To evaluate the association of upper extremity musculoskeletal disorders with job demand-control and effort-reward related job stress.

Questionnaires concerning symptoms, psychosocial factors and work conditions were completed by 436 workers from a refrigerator assembly line, mobile phone assembly line, and an office, musculoskeletal conditions of the upper extremities were defined by the frequency, duration, and intensity of symptoms. A walk-through survey was performed to evaluate various physical work factors. Data were analyzed with the use of logistic regression.

A total of 382 workers completed the survey, for whom neck and shoulder symptoms were the most frequently reported, followed by finger and wrist, and then elbow symptoms. Both awkward working posture and forceful exertion were associated with an increase in shoulder/neck and finger/wrist symptoms. In addition, job stress factors such as monotony, low job clarity, low job control, low promotion prospect, economic issues, and retirement pressures were associated with increased neck/shoulder, elbow, and finger/wrist conditions. Women were more likely to report symptoms, and the association between musculoskeletal conditions and job stress factors was stronger in female assembly line workers and office workers than in male assembly line workers.

The results suggest that musculoskeletal conditions of the upper extremities are associated with not only physical work factors but also job stress factors. In particular, economic issues and career development factors are important influences on workers in Korea.