Assessment of upper limb musculoskeletal pain and posture in workers of packaging units of pharmaceutical industries.

BACKGROUND: Work-related musculoskeletal disorders are defined as the disabling or painful injury to the muscles, nerves or tendons that are caused by work or aggravated by it. Some studies confirm the association between working in packaging units in various industries and the pain in the upper limb, but also there are controversies about the possible risk factors among different working populations.

OBJECTIVE: The present study aims to define the potential ergonomic risk factors for musculoskeletal pain in the upper limb.

METHODS: The Nordic Musculoskeletal Questionnaire was used for assessment of the musculoskeletal pain. Some other questions about the possible risk factors were included in the questionnaire. In order to assess posture, rapid upper limb assessment (RULA) test was performed by trained ergonomists.

RESULTS: The findings of the study reveals that shoulder pain is associated with work history (P-value = 0.01), smoking (P-value = 0.02), the level of education (P-value = 0.04) and age more than 40 years old (P-value = 0.01). Wrist pain was associated with shiftwork (P-value = 0.04) and especially fixed shiftwork (P-value = 0.04) and also age more than 40(P-value = 0.03) and missed days from work with a cut point of 7 days (P-value = 0.03). After regression, only the work history (OR = 14.4 for 10 to 20 years and OR = 32.2 for more than 20 years) and shiftwork (OR = 2.35) remained statistically significant.

CONCLUSIONS: In this study, RULA was not associated with symptoms in the upper limb in non-heavy working industries so we do not recommend it for screening purposes. The use of decades of working history and shiftwork can be considered for this purpose in the shoulder and wrist pain respectively.