Objective: To investigate the incidence of shoulder work-related musculoskeletal disorders (WMSDs) among occupational population in China, and to explore their intrinsic association with personal and work-related factors. Methods: In April 2024, 73497 valid questionnaires of the Chinese version of the Musculoskeletal Disorders Electronic Questionnaire were retrospectively analyzed from June 2018 to December 2023 in 22 provinces and 29 key industries in China, and the general information, occurrence of WMSDs and related risk factors of key occupational populations in different regions in China were collected. By using Chi-square test and confirmatory factor analysis, the relationship between shoulder fatigue and pain in key occupational groups and individual factors, work type, work posture and work organization was discussed, and the internal relationship was analyzed based on structural equation model. Results: Higher incidence of shoulder fatigue and pain were associated with female, lack of physical exercise, uncomfortable working posture and neck leaning forward (P<0.05). Structural equation model analysis showed that work type, work posture and work organization were strongly correlated (r=0.58, 0.55). Work organization and work type were strongly correlated with shoulder fatigue (r=0.65) and moderately correlated with shoulder fatigue (r=0.21). Shoulder fatigue was moderately associated with shoulder pain (r=0.40). Individual factors, work type, work posture and shoulder fatigue could directly affect shoulder pain (OR=0.07, -0.09, 0.17 and 0.40), and work type and work posture could also indirectly affect shoulder pain through shoulder fatigue (OR=0.08, 0.03). Work organization only indirectly affected shoulder pain through shoulder fatigue (OR=0.26) . Conclusion: The main influencing factor of shoulder pain is shoulder fatigue, followed by work posture and individual factors. Structural equation model can better reflect the complex relationship between work type, work posture and work organization and shoulder WMSDs. Improving work posture and work organization may be an effective way to control the influence of shoulder fatigue on shoulder pain.
目的： 调查我国职业人群肩部工作相关肌肉骨骼疾患（work-related musculoskeletal disorders，WMSDs）发生率，并探索其与个人和工作相关因素的内在联系。 方法： 于2024年4月，回顾分析2018年6月至2023年12月我国22个省份、29个重点行业的73 497份《中文版肌肉骨骼疾患电子问卷》，收集不同地区重点职业人群的一般资料、WMSDs发生情况及其相关危险因素等信息。综合运用χ(2)检验、验证性因子分析，探讨重点职业人群肩部疲劳及疼痛与个体因素、工作类型、工作姿势和工作组织的关系，并基于结构方程模型分析其内在联系。 结果： 女性、缺乏体育锻炼者、以不舒服的姿势工作和工作时颈部大幅前倾者均与较高的肩部疲劳、疼痛发生率有关（P<0.05）。结构方程模型分析显示，工作类型、工作姿势与工作组织呈强相关（r=0.58、0.55）；工作组织和工作类型与肩部疲劳分别呈强相关（r=0.65）和中等相关（r=0.21）；肩部疲劳与肩部疼痛呈中等相关（r=0.40）。个体因素、工作类型、工作姿势和肩部疲劳均可直接影响肩部疼痛（OR=0.07、-0.09、0.17、0.40），工作类型和工作姿势还可通过肩部疲劳间接影响肩部疼痛（OR=0.08、0.03），而工作组织仅通过肩部疲劳间接影响肩部疼痛（OR=0.26）。 结论： 肩部疼痛的主要影响因子是肩部疲劳，其次是工作姿势、个体因素。结构方程模型更好地反映了工作类型、工作姿势和工作组织与肩部WMSDs之间复杂相关关系，改善工作姿势和工作组织可能是控制肩部疲劳对肩部疼痛影响的有效方法。.
Keywords: Musculoskeletal system; Shoulder fatigue; Shoulder pain; Structural equation model; Work-related musculoskeletal disorders.