Prevalence and associated factors of musculoskeletal disorders among Chinese healthcare professionals working in tertiary hospitals: a cross-sectional study

Musculoskeletal disorders (MSDs) are prevalent in working populations around the globe [1‐6]. Long-term and severe MSDs could affect quality of life, reduce work productivity, increase sick leave absence, shorten working life and cause chronic occupational disability and constitute a major health challenge for individuals and healthcare systems around the world [5, 7, 8]. Numerous workplace hazard exposures and demographic and psychosocial risk factors have been demonstrated to be associated with MSDs, such as awkward postures, repetitive movements, high-pressure forces and other factors, including age, sex, body mass index (BMI) and stress [9‐13]. Some occupational groups are at an increased risk of developing MSDs due to the nature of their job duties.

Healthcare professionals (HCP) in hospitals, as a special occupational group, engage in a large number of job-related tasks and experience relatively high levels of mental stress while caring for patients [14, 15]. Many studies [13, 16‐23] have revealed that MSDs occur commonly in HCP, for example, 50 to 93% in nurses, 86.7% in 503 vaginal surgeons, 67% in 402 orthopaedic paediatric surgeons and 91% in 211 sonographers. In Mainland China, with the development of the economy and the improvement in people’s spending power, an increasing number of patients are inclined to go to large hospitals to seek medical services. Considering shortages in medical staff, the large Chinese population base, an aging population, and unevenly distributed medical resources, the workload of HCP may be heavy, especially in general hospitals, which could result in extended working hours or an increased pace of the work and subsequently expose HCP to additional hazards. In addition, long working hours and intense schedules could lead to high levels of mental stress and fatigue in the workplace, which could then aggravate MSDs.

In Mainland China, although a high prevalence of MSDs among some groups of HCP had been reported in a few studies, such as a 12-month period prevalence of 98.3% in 381 sonographers and 85.6% in 271 dental postgraduates [24‐26], these studies were either small scale, only considered one hospital of workers or focused on particular subgroups of HCP. No large-scale or multi-centre-based studies have been conducted in Mainland China, and to our knowledge, little is known about the prevalence and risk factors of MSDs in Chinese HCP. In addition, not enough attention has been paid to the occupational health risks (psychological, ergonomic and organizational factors and workload) of HCP in China. The purpose of our study was to determine the prevalence of work-related MSDs among HCP in tertiary hospitals in Mainland China and to quantify the relationships of potential factors associated with MSDs in various body locations.

The mean age of the 14,720 respondents was 33.8 ± 8.6 years (ranging from 19 to 63 years), including 5351 male subjects (36.4%) and 9369 female subjects (63.6%). Among the participants, the average number of years worked was 10.7 ± 7.9 years (ranging from 1 to 43 years). The participants were all well-educated, with at least twelve years of education.

The 12-month period prevalence of MSD in at least one body site for at least 24 h, at least 7 days and at least three months was 91.2, 58.3 and 17.1%, respectively. Pain and discomfort were mostly found in the lower back (72.8, 50.7, 14.3%, respectively), knees (65.7, 42.9, 8.1%), shoulders (52.1, 35.2, 6.2%), and neck (47.6, 28.9, 4.8%), followed by wrists/hands (31.1, 23.8, 3.2%), ankles/feet (23.6, 15.1, 1.9%), upper back, hips/thighs and elbows. The proportions of MSDs among the different body sites were significantly different (p < 0.001). For more details, see Table 1.

Of those who reported MSDs, 68.3% reported that they had sought health care for the MSD in the preceding twelve months. When asked about MSD knowledge, most HCP reported that they had not received any MSD education outside of work.

Multivariable logistic regression analysis revealed that the following factors were associated with lower back MSDs: work hours per week, break times during workday, bending the trunk frequently, heavy or awkward lifting, bending or twisting the neck, psychological fatigue, mental stress, employment status, age and sex (Table 2). Regarding knee-related MSDs, there were associations with the following factors: work hours per week, break times during workday, standing for long periods of time, walking for long periods of time, psychological fatigue, mental stress, employment status, age and BMI (Table 3).

Multivariable analysis found that shoulder MSDs were associated with work hours per week, break times during workday, maintaining shoulder abduction for long periods of time, bending or twisting the neck, psychological fatigue, mental stress, employment status and age (Table 4).

In this multi-centre large-scale survey of HCP and work-related MSDs and associated factors, the HCP were sampled from eight tertiary hospitals selected by random cluster sampling from among all tertiary-level hospitals in Shandong Province, and the response rate of 93.3% was comparable to or higher than those reported in previous studies [20, 23, 32, 33]. Therefore, the sample can be considered representative of HCP working in tertiary hospitals in Shandong, China. We found that MSDs were common among HCP working in tertiary hospitals, with the most frequently reported MSDs in the lower back, knee, shoulder and neck regions. Most HCP had not received any MSD education outside of work and lacked the basic knowledge of MSD prevention. The high MSD prevalence among HCP was associated with workload (work hours per week, break times during work day), ergonomic factors (bending the trunk frequently, heavy or awkward lifting, bending or twisting the neck, walking for long periods of time, standing for long periods of time, maintaining shoulder abduction for long periods of time), psychosocial factors (mental stress and psychological fatigue in the work place), and employment status, in addition to demographic factors (age, sex and BMI).

In this study, the 12-month prevalence rate of MSDs lasting for at least 24 h in any body region was 91.2%, which was lower than that among HCP in Brazil (93%) [21], similar to that among HCP in Nigeria (90.7%) [34] and in Japan (91.9%) [35], but higher than that among HCP in other countries (31–78%) [19, 32, 36]. Similar to previous studies [19, 21], our study found the highest 12-month prevalence rate of MSDs in the lower back, knees, shoulders and neck. The highest prevalence of the 12-month period MSDs among HCP in this study was 72.8% (in the lower back), which was lower than that among HCP in Nepal (78%) [33], similar to that among HCP in Turkey (70.1%) [1], Iran (73.2%) [37] and Nigeria (73.5%) [23], but higher than that among HCP in Sweden (64.0%) [38], England (45.0%) [39], the US (29.0%) [40], and Hong Kong (40.6%) [41]. The prevalence of knee and shoulder MSDs in the present study was 65.7 and 52.1%, respectively, which was also similar to or higher than that among HCP in other studies [35, 37, 42‐44]. The prevalence rate of lower back MSDs lasting for at least three months observed in our study was 14.3%, which was higher than that observed in the Netherlands (12%), Greece (11%) [45] and Taiwan (8.6%) [10]. The prevalence of MSDs has been found to vary over national boundaries and across occupational groups [35], and there are variations in measurement instruments, subjectivity of terms, cultural differences in the perception and reporting of MSDs and organizational differences in work environments that contribute to the variation in prevalence rates of MSDs assessed by different surveys. Compared with the studies listed above, the prevalence of MSDs among HCP working in tertiary hospitals in Mainland China were quite high.

The research showed that bending the trunk frequently, heavy or awkward lifting, bending or twisting the neck, walking for long periods of time, standing for long periods of time, and maintaining shoulder abduction for long periods of time contributed to healthcare workers’ MSDs, which was in agreement with findings of previous studies [16‐18, 29, 46]. However, the associated ergonomic factors for different body regions MSDs were different. Bending the trunk frequently, heavy or awkward lifting and bending or twisting the neck were shown to be factors associated with MSDs in the lower back, consistent with previous studies [29, 39]. Walking for long periods of time and standing for long periods of time contributed to knee MSDs, which was similar to a previous study [32]. MSDs in the shoulder region were linked to maintaining shoulder abduction for long periods of time and bending or twisting the neck, which were consistent with results from another study [22]. In the present study, bending or twisting the neck was noted to be associated with lower back and shoulder MSDs, probably because bending or twisting the neck may appear together with other awkward postures, such as bending the trunk, maintaining shoulder abduction for long periods of time, heavy or awkward lifting and other trunk postures [29]. This finding might suggest the need for a proposal of ergonomic training and education about MSD prevention for hospital HCP in Mainland China. In addition, when exploring preventive measures, different ergonomic factors that target the prevention of MSDs in different body regions should be considered.

With increasing work hours per week and fewer break times during the workday, MSDs increase significantly, possibly because longer work hours results in a longer period of maintaining a poor posture, increased exposure to high-pressure forces and more repetition. As indicators of workload, work hours per week and break times during the workday have been identified as risk factors of lower back pain in hospital nurses [23]. Considering the fact that Chinese people tend to go to large and comprehensive hospitals when seeking medical services, patients with minor ailments or patients having an initial doctor visit should be discouraged from going to the large hospitals, and the availability of tiered medical service needs to be improved. Measures also need to be taken to limit the maximum number of patients cared for per worker and the maximum working hours per week in tertiary hospitals to limit exposure to the factors associated with MSDs.

Our study also showed that contract/temporary HCP were more prone to experiencing MSDs than permanent HCP. Previous studies [47, 48] have suggested that temporary or contract employees experience more job insecurity than permanent employees. In China, the recruitment of permanent personnel is approved by the local government, the requirements are more stringent, and accordingly, their job stability is greater; in contrast, temporary or contract employees are recruited by the hospital itself and the employee’s job stability is decided largely by the hospital, not themselves, based on the fact of more job applicants for fewer positions. Job insecurity has been identified as an important occupational stress factor [49] and negatively contributes to the psychological and physical health and well-being of employees [50‐52]. Contract or temporary HCP were more likely to be stressed for these reasons and to work harder to keep their job, which might lead to the occurrence or aggravation of MSDs.

In our study, psychosocial factors (mental stress and psychological fatigue in the workplace) were shown to be associated with MSDs. HCP who experienced a high level of psychological fatigue seemed more likely to present with MSDs. The effect of psychosocial factors on MSD has been supported by other studies [53, 54]. Researchers in the US [53] have suggested an association between psychological stress and a higher presentation of MSD symptoms in the lower back among full-time employees, who were mostly from retail service industries (e.g., customer service representative) and professional industries (e.g., nurses). This association may be caused by the stress of the necessity for accurate and fast critical care treatment, the tense scheduling, and the high job demands of HCP in tertiary hospitals. Therefore, job design may be optimized, and the working environment may be improved. Measures that could be recommended in tertiary hospitals to relieve occupational stress include slowing down the pace of the work, conflict resolution and supportive group systems.

As to the limitations, this cross-sectional study precludes identifying the causal influence among the associated factors and MSDs. Another limitation is that our study ignored the quantitative interactions between occupational, psychosocial, and demographic factors. A prospective cohort study design may be needed in the future to provide more sound research evidence. Like all other cross-sectional or self-report studies, it is possible that our respondents might have given vague answers or exaggerated their MSDs. As musculoskeletal ultrasound has become a validated and economically viable tool to screen neuromuscular and musculoskeletal disorders, it would be better to consider this portable tool for future studies, and it was a limitation of our study for not using it. This study was limited to HCP in active service only, thus those who had left the workforce due to MSDs or any other reason were not included in the current analysis.

This study suggested an extremely high prevalence of MSDs in Chinese HCP working in tertiary hospitals. The associated factors were workload (work hours per week, break times during the work day), occupational factors (bending the trunk frequently, heavy or awkward lifting, bending or twisting the neck, walking for long periods of time, standing for long periods of time, and maintaining shoulder abduction for long periods of time), psychosocial factors (mental stress and psychological fatigue in the work place), and contract/temporary employment status, in addition to demographic factors. The factors associated with MSDs and identified in the present study need to be considered when exploring effective and concrete intervention strategies for MSDs.