Objective: To investigate the prevalence and risk factors of occupational musculoskeletal disorders among workers in heavy-duty automobile parts factories in Beijing Municipality, so as to provide insights into development of effective interventions for occupational musculoskeletal disorders. Methods: The workers in three heavy-duty automobile truck parts factories in Beijing Municipality were recruited using the convenient sampling method during the period from May 2019 to October 2020. Subjects' demographic characteristics, type of job and prevalence of occupational musculoskeletal disorders at various sites were collected using self-designed electronic questionnaires, and the factors affecting the development of occupational musculoskeletal disorders were identified using a multivariable logistic regression model. Results: A total of 264 workers were enrolled, including 260 males (98.48%) and 4 females (1.52%). The participants had a mean age of (31.71±6.13) years, and mean duration of (7.51±5.25) years at current position, and mechanical technician was the major type of work (129 workers, 48.86%). The prevalence of occupational musculoskeletal disorders was 70.08% among the participants, and high prevalence of occupational musculoskeletal disorders was found in the lower back/waist (41.28%), shoulder (40.15%), neck (39.02%) and upper back (33.33%). Multivariable logistic regression analysis identified females (OR=1.280, 95%CI: 1.021-1.602) and head-down posture at work (OR=2.644, 95%CI: 1.034-6.763) as risk factors for occupational musculoskeletal disorders at neck; females (OR=1.633, 95%CI: 1.624-2.117), sheet metal workers, mechanical technicians and painters (OR: 5.811-10.452, 95%CI: 1.205-54.027), working in an uncomfortable posture (OR：1.376-7.749, 95%CI: 1.034-27.270) and frequent working overtime (OR=2.081, 95%CI: 1.192-4.137) as risk factors for occupational musculoskeletal disorders at shoulder; and sheet metal workers, mechanical technicians and painters (OR: 8.760-11.948, 95%CI: 1.630-66.927), working in an uncomfortable posture (OR：4.067-12.185, 95%CI: 1.332-47.523) and frequent working overtime (OR=2.201, 95%CI: 1.142-4.244) as risk factors for occupational musculoskeletal disorders at waist/back. Conclusions The prevalence of occupational musculoskeletal disorders is high among workers in heavy-duty automobile parts factories, which mainly occur at shoulder, neck, waist and back. Type of work, working posture and working duration are main factors affecting the development of occupational musculoskeletal disorders.

{L-End}Objective To analyze the prevalence of multi-site work-related musculoskeletal disorders (WMSDs) and their influencing factors among workers in the chemical pharmaceutical industry. {L-End}Methods A total of 563 workers from three chemical pharmaceutical factories in Guangzhou City were selected as the research subjects using the judgment sampling method. The prevalence of multi-site WMSDs in the past 12 months was investigated using the electronic questionnaire of Chinese Version of Musculoskeletal Disorders Questionnaire. {L-End}Results The prevalence of multi-site WMSDs in the research subjects was 30.0% (169/563). The results of multivariable logistic regression analysis showed that workers who smoked regularly/frequently and those who had their hands above shoulder level for long periods of time had a lower risk of multi-site WMSDs than those who never/occasionally smoked (all P≤0.05). Workers with a high school, secondary specialty, college degree, or above had a lower risk of multi-site WMSDs than those with a middle school education or below (all P<0.05). The longer the daily working hours, the higher the risk of multiple WMSDs (all P<0.05). Workers with regular/frequently work shifts had a lower risk of multi-site WMSDs than those with none/occasional work shifts (P<0.05). {L-End}Conclusion The prevalence of multi-site WMSDs among workers in the chemical pharmaceutical industry is relatively high. The influencing factors are individual factors, unreasonable work organization and poor ergonomics factors.

AIM: To explore the effect of spinal anesthesia on ventricular arrhythmia and involved mechanisms in myocardial ischemia-reperfusion (MIR) rats. METHODS: The rat MIR model was made by occlusion the left anterior descending coronary artery for 30 minutes and reperfusion for 45 minutes. Bupivacaine (0.05 mL / 100 g, 1 mg / kg) was injected slowly via intrathecal for spinal anesthesia. The electromyelogram at T2 thoracic spinal cord was recorded. Ventricular arrhythmias, cardiac function, myocardial damage were assessed by electrocardiography, echocardiography and TTC or HE staining. RESULTS: MIR reduced left ventricular short-axis shortening (LVFS) and left ventricular ejection fraction (LVEF), caused myocardial histological damage and ventricular arrhythmias, promoted spinal electrical discharge frequency and amplitude in T2 dorsal horn. Spinal injection of bupivacaine could significantly reduce spinal cord electrical activities and eliminate MIR-induced arrhythmias. Moreover, bupivacaine also significantly improved MIR-induced myocardial histological damage and cardiac function inhibition. CONCLUSION: Spinal anesthesia can reduce ventricular arrhythmias induced by MIR. The mechanism may be related to the effect of abolishing spinal nerve excitability.

Background Work-related musculoskeletal disorders (WMSDs) are one of the major occupational health problems in the world. Pharmaceutical industry is an important part of China's national economy. At present, there are few related studies reported at home and abroad. Objective To investigate the status and influencing factors of WMSDs in chemical pharmaceutical industry. Methods A cross-sectional epidemiological survey was conducted among all workers from three chemical pharmaceutical enterprises in Guangzhou. The Musculoskeletal Disorders Questionnaire was used to collect information on demographic characteristics, symptoms of musculoskeletal disorders, types of work, work organization, and and work postures. Multiple logistic regression method was used to analyze the risk factors of WMSDs in chemical pharmaceutical workers. Results In this study, 563 workers were selected as subjects. The total prevalence rate of WMSDs symptoms in the chemical pharmaceutical workers was 43.9% (247/563), and the leading body part-specific prevalence rate from high to low was 34.3% in the lower back, 24.3% in the upper back, 24.0% in the shoulders, and 23.8% in the neck. The prevalence rate of WMSDs symptoms in multiple body parts (30.0%) was 2.16 times higher than that in single body part (13.9%), and the prevalence rate of WMSDs symptoms in four body parts was the highest (11.4%). The results of multiple logistic regression analysis showed that age ≥50 years (reference age <30 years) (OR=2.140, 95%CI: 1.054-4.345), often or very often (reference never/rarely) long-time head rotating (OR=2.695, 95%CI: 1.753-4.142) and long-time keeping arms above shoulders (OR=1.902, 95%CI: 1.108-3.265) increased the risk of reporting WMSDs symptoms (P<0.05). Regarding education level, workers with high school and technical secondary school (OR=0.333, 95%CI: 0.175-0.636) or college and above (OR=0.413, 95%CI: 0.216-0.790) education had a lower risk of reporting WMSDs symptoms than those with middle school or below (P<0.05). Conclusion The prevalence rate of reporting WMSDs symptoms in chemical pharmaceutical industry is high, the involving body parts are lower back, upper back, shoulders, and neck, and reporting simultaneous occurrence of WMSDs symptoms in multiple body parts is common. The chemical pharmaceutical manufacturers can reduce the risk of WMSDs by strengthening the training on workers' ergonomics knowledge, paying attention to the less educated personnel, protecting the elderly workers, and avoiding awkward work postures, like rotating head for a long time and raising arms over shoulders.