Work-related Musculoskeletal Disorders Among Machinery Manufacturing Factory Workers in a Chinese Factory

The prevalence of work-related musculoskeletal disorders (WMSDs) is high among workers in the machinery manufacturing industry yet effective prevention and control measures are currently lacking.

This study recruited 226 workers from a machinery manufacturing factory in Huaibei City. The prevalence of WMSDs was investigated by a modified Chinese version of the questionnaire based on the Nordic Musculoskeletal Questionnaire and the Dutch Musculoskeletal Questionnaire. The risk factors of WMSDs were explored by structural equation modeling and multiplicative interaction models based on logistic regression.

The prevalence of WMSDs among workers from a machinery manufacturing factory was 86.28%, with the highest prevalence of lower back pain (62.38%) and the lowest prevalence of thigh/hip joint (26.99%) among the nine affected areas. The structural equation models indicated a negative correlation between body postures in work and musculoskeletal health, regardless of static, dynamic, or combined static-dynamic work. The multiplicative interaction model showed that the duration and frequency of lateral head bending were negatively associated with neck health (odds ratio [OR]: 0.071, 95% confidence interval [CI]: 0.018-0.281) and shoulder health (OR: 0.028, 95%CI: 0.001-0.692).

The survey revealed the prevalence of WMSDs in a machinery equipment manufacturing factory reached 80%. This study combined structural equation modeling with multiplicative interaction to explore the relationships between WMSDs and poor ergonomic postures under dynamic, static, and combined dynamic-static working conditions. The results demonstrated a negative association between poor ergonomic postures and musculoskeletal health. In the future, intervention studies targeting poor ergonomic postures will be critical for the prevention of WMSDs.