Association of lower extremity work-related musculoskeletal disorders and types of working among manufacturing workers / 中国职业医学

ABSTRACT

OBJECTIVE: To investigate the prevalence of lower extremity work-related musculoskeletal disorders(WMSDs) among manufacturing workers, and to explore the association of lower extremity WMSDs and different types of working. METHODS: A total of 7 908 workers were selected as study subjects from four manufacturing factories in China using the cluster sampling method. The Musculoskeletal Disorders Investigating Questionnaire was adopted to investigate the prevalence of lower extremity WMSDs and the distribution of types of working. The prevalence ratio(PR) of WMSDs, calculated by log-binomial model, was used to estimate the correlation of WMSDs in different parts of lower extremity. The multi-factor logistic regression was used to analyze the association of lower extremity WMSDs and different types of working. RESULTS: The total annual prevalence of lower extremity WMSDs was 41.0%(3 241/7 908) among manufacturing workers. The annual prevalence of WMSDs of different parts in lower extremity from high to low were knee(29.5%), ankle/foot(23.9%) and hip/thigh(16.7%). The correlation of WMSDs of the three parts in lower extremity was close, and the range of PR values was 2.21-3.88. The result of logistic regression analysis showed that the workers who frequently sat for long periods had higher risk of lower extremity WMSDs than those who never/rarely sat for long periods(odds ratio=1.39, P<0.01). The higher the frequency of standing, kneeling/squatting for long periods, carrying heavy loads ≥5 kg and driving, the higher the risk of lower extremity WMSDs(the odds ratios were 1.33, 1.41, 1.16 and 1.12, respectively, P<0.01). CONCLUSION: The prevalence of lower extremity WMSDs was relatively high among manufacturing workers. There is a dose-effect relationship between the types of working and lower extremity WMSDs.