Abstract:
Background
Work-related musculoskeletal diseases (WMSDs) occur in a variety of occupational populations. Because of their various discomfort and serious disease burden, they have become an important issue worthy of attention in the field of occupational health. The prevention and control of WMSDs is one of the public health problems to be solved.
Objective
To evaluate the intervention effect on WMSDs among assembly workers in a railway vehicle manufacturing enterprise, so as to provide scientific basis for the prevention and control of WMSDs.
Methods
A total of 250 assembly workers in a railway vehicle manufacturing enterprise were selected using convenience sampling from August to December 2017. The Chinese Musculoskeletal Questionnaire was used for epidemiological investigation, and the Ergonomic Checkpoints was used for ergonomic inspection and worker interview. According to the above survey results, a six-month intervention plan including stepladder improvement and ergonomics training were implemented in the assembly workshop from September 2018 to February 2019. The intervention effects including the awareness of WMSDs, the exposure level of ergonomic load, and the occurrence of WMSDs symptoms were evaluated with relevant cross-sectional survey results before and after the intervention. The scores of WMSDs symptom intensity, symptom duration, and symptom frequency from low to high were 0-10, 1-4, and 1-5, respectively.
Results
After the intervention, the awareness rates of assembly workers on WMSDs types, affected body sites, influencing factors, preventive measures, and symptoms all increased from 52.3%, 51.9%, 25.5%, 19.1%, and 51.5% to 68.5%, 61.3%, 48.1%, 40.9%, and 61.3%, respectively (P<0.05). After the intervention, the proportion of assembly workers who "often" bend their head backwards frequently decreased from 34.6% to 21.8%, the proportion who "often" keep their trunk backward for a long time decreased from 26.6% to 15.0%, and the proportion who "never" raise their arms frequently increased from 3.4% to 9.0% (P<0.05). After the intervention, the scores of WMSDs symptom intensity in neck, shoulders, upper back, low back, elbows, hands/wrists, hips/thighs, knees, and ankles/feet all decreased, and the medians were mostly decreased from 6 to 3 (P<0.05); the scores of WMSDs symptom duration only decreased in neck (P<0.05) and there was no significant difference in the other body sites before and after the intervention; the median scores of WMSDs symptom frequency in low back, hands/wrists, and hips/thighs decreased from 3 to 2 (P<0.05).
Conclusion
The six-month intervention of stepladder improvement and ergonomics training among assembly workers in a railway vehicle manufacturing enterprise can improve workers' awareness of WMSDs, and reduce the exposure frequency of awkward postures and the intensity, duration, and frequency of WMSDs symptoms.