[Study on work-related musculoskeletal disorders and influencing factors of underground workers in a coal mine]

Objective: To investigate the occurrence of work-related musculoskeletal disorders (WMSDs) among underground coal mine workers, identify the risk factors for WMSDs, and provide a scientific evidence for the prevention and treatment of WMSDs. Methods: In March 2024, through cluster sampling, the on-the-job workers who underwent questionnaire surveys and health examinations at a certain coal mine from July to August 2018 were selected as the research subjects. Basic information of employees, ergonomics-related characteristics, and the occurrence status of WMSDs in each part were collected, and multivariate logistic regression was used for analysis. Results: The incidence rate of WMSDs in at least one site among underground coal mine workers within the past year was 62.22% (219/352). The top three sites in sequence were the lower back (44.32%, 156/352), neck (26.14%, 92/352), and knee (26.14%, 92/352). Multivariate logistic regression analysis showed that frequently exerting great force with arms or hands during work (OR=2.223, 95%CI: 1.022-4.836), prolonged static forward bending (OR=1.544, 95%CI: 1.305-1.972), and frequently exerting great effort to operate tools or machines (OR=2.206, 95%CI: 1.011-4.813), absence of external support systems (OR=1.589, 95%CI: 1.349-1.996), and repetitive full-body twisting (OR=1.523, 95%CI: 1.298-1.916) were all risk factors for the occurrence of WMSDs in the lower back (P<0.05). Both night shift work (OR=1.564, 95%CI: 1.339-1.939) and frequent forward neck flexion (OR=1.532, 95%CI: 1.312-1.907) were all risk factors for the occurrence of WMSDs in the neck (P<0.05). Lifting heavy objects above the shoulder (OR=1.333, 95%CI: 1.142-1.782), uncomfortable posture and inability to exert force (OR=1.873, 95%CI: 1.104-2.712), the use of vibration tools (OR=2.958, 95%CI: 1.255-6.972), and length of service >10 years (OR=1.525, 95%CI: 1.105-1.967) were all risk factors for the occurrence of WMSDs in the knee (P<0.05) . Conclusion: The incidence of WMSDs among underground coal miners is relatively high, mainly concentrated in the lower back, neck and knee, and is related to factors such as poor working postures, and work organization. Coal mining enterprises should strengthen work organization, provide appropriate working equipment, and ensure reasonable distribution of workloads.