Prevalence of musculoskeletal disorders among school teachers from urban and rural areas in Chuquisaca, Bolivia: a cross-sectional study

Musculoskeletal disorders (MSD) have been reported as one of the most common and important health problems in working populations, generating social and economic implications [1]. In teachers, prevalence of MSD was found to range between 39% and 95% [2]. In general, they reported more frequently back, neck and upper limbs problems although there have been marked differences between the type of teacher and the body part affected.

Teachers working conditions in rural schools face greater challenges than in urban areas, such as social and geographic isolation, poor working conditions, poor remuneration, limited opportunities for professional improvement, lack of adequate resources, careless buildings, cultural differences and poor community involvement [3, 4]. Additionally educational system in many countries has no adequate strategies to attract and retain competent and qualified teachers [5], impacting on working conditions with greater limitations in rural schools.

Some studies reported that physical factors such as prolonged standing, sitting and uncomfortable posture are known to be associated with increased prevalence of MSD [6]. In addition, several studies suggest that psychosocial factors including high workload and demands, high perceived stress levels, low social support, low job control, low job satisfaction and monotonous work are associated with MSD among school teachers [7]. In this sense, it is possible that teachers in rural areas may be more exposed to develop musculoskeletal disorders.

In Bolivia, teachers and administrative staff working in the educational sector represent the largest public workforce (around 100,000 workers) [8]. According to the World Bank, expenditure of the Bolivian Government on education increased from 5.7% in 1999, to 6.4 in 2012 [9]. Chuquisaca, one of the nine departments (regions) in Bolivia, is located in the south part of the country. It has an estimated population of 616,073 inhabitants from which 50.2% are living in rural areas [10]. Illiteracy rate in Chuquisaca is around 8 to 37%, school attendance between 69 to 89% and coverage for primary education 86.2%, lower than the national coverage (92%) [11]. As in other Latin American countries, educational indicators in Bolivia and in Chuquisaca show big differences between urban and rural areas with lower educational levels and more unfavorable working conditions in rural areas [11‐13].

Working and health conditions in Latin-American and especially in Bolivian teachers have been scarcely explored. In the same way, there are few reports exploring health conditions in teachers working in rural areas. Therefore the objectives in our study were to determine the prevalence of musculoskeletal disorders considering the whole body and to compare differences between schools teachers working in rural and urban areas of Chuquisaca, Bolivia.

A cross-sectional study was conducted in Chuquisaca, Bolivia from August to November 2015.

A total of 620 teachers returned the complete questionnaire reaching response of 58% (57% in urban and 59% in rural schools). For analysis, 103 questionnaires were excluded because participants were administrative staff (N = 19) or did only complete the questionnaire partially (N = 84). There were no statistically significant differences in descriptive variables between included and excluded teachers.

In rural areas compared to urban areas, teachers were statistically significantly younger, more likely to be male, to work at the secondary level and to work at a public school (Table 1).

The period prevalence of MSD in any region was 86%, 63% and 15% for the last 12-months, 7-days and 12-months prevalence of work limiting pain respectively and 48%, 26% and 5% for musculoskeletal disorders in three or more parts of the body (Table 2). In general, rural area showed a higher prevalence of MSD although the difference was not statistically significant for all outcome definitions.

The 12-months prevalence of musculoskeletal disorders ranged from 26% for wrist/hands to 47% for neck. Only for neck and knee disorders the prevalence was higher in urban areas. Following the same pattern, 7-day prevalence ranged from 14% for disorders in wrist/hands to 31% for neck disorders. For work limiting pain during last 12-months it ranged from 3% for wrist/hands to 6% for neck (Table 2).

The adjusted logistic regression models basically confirmed the bivariate analyses: teachers working in rural areas reported statistically significantly higher odds than teachers from urban schools for any work limiting musculoskeletal pain during the last 12-months prior to survey (aOR 2.2; 95% CI 1.1–4.1) and for work limiting pain in at least 3 parts of the body (aOR 3.7; 95% CI 1.3–10.6) (Table 3). For specific parts of the body, work-limiting pain in ankles or feet was higher in rural than in urban teachers (aOR 4.4; 95% CI 1.4–13.7). No statistically significant differences were seen for the 12-months nor the 7-days prevalence of symptoms regardless of body part in these adjusted models.

This study aimed to explore self-reported musculoskeletal disorders (MSD) considering 12-months and 7-days prevalence as well as the 12-months prevalence of work limiting pain comparing teachers from urban and rural schools. Prevalence of MSD was high and especially work-limiting pain was more common in teachers employed at rural than in those working in urban schools.

Our results showed considerable prevalence of MSD affecting several parts of the body maybe due to the variety of activities that teachers perform each day at work. Almost half of the participants reported MSD in ≥ 3 parts of the body during the last 12-months and 26% during the last 7-days. It is relatively high if we compare with Brazilian teachers, where 7-days prevalence (≥ 3 parts of the body) was 15.9% in 2011 [20]. This could be explained due to differences in geographic context. Brazilian study comprised metropolitan area with high Municipal Human Development Index (0.717) than the region studied in Bolivia (0.563) [21], and probably working and living conditions are different.

In agreement with previous studies, we found considerable prevalence of disorders reported in the neck and upper extremities but also in back and lower extremities [2]. Although the main focus of the present study is to compare the prevalence of musculoskeletal disorder in urban and rural areas, a major limitation of the study is the lack of inclusion of risk factors that explain these differences. Individual factors, as well as working conditions under which the teachers perform their work could explain the presence of specific musculoskeletal disorders for each region of the body. MSD in neck and upper extremities can be a consequence of the significant use of uncomfortable physical activities, like ‘head down’ posture, during reading, writing on a blackboard or marking of assignments for several hours [22, 23]; but also back and lower extremities could be affected due to long hours standing while teaching [24], postural overloads in the classroom, uncomfortable back support while seated, recurrent twisting, and prolonged static postures [25]. Additionally teachers face every day social and psychological demands inside and outside the school [26, 27], and have reported less time for rest after work, because of extra work at home [28], which could lead in chronic and disabling musculoskeletal disorders [29]. Little information is available about work limiting pain prevalence in teachers. Our results reported a prevalence around 15% for any musculoskeletal disorder, lower than previously reported. One study in Brazilian public school teachers found a prevalence of work-limiting pain in any part of the body of 47.4% [30], also Converso et al. reported a prevalence of 42.9% suffering moderate to severe limiting musculoskeletal pain in nursery school and kindergarten teachers in Italy [31]; In the same way staff at special schools in Germany reported a prevalence of chronic back pain of 27.6% [32]. This difference could be explained, because those studies explored MSD mainly in teachers from special schools, where physical demands as frequently carrying and lifting heavy loads must be taken into consideration.

This is the first study comparing working and health conditions in teachers working in urban and rural areas in Bolivia. Our study showed higher MSD prevalence in rural areas, especially for work-limiting pain independently to age, sex, teaching level and school type. Living and working conditions in rural areas of Bolivia, represents a great challenge for professionals, especially because limited geographic access, bad road conditions, distancing from the family and poor social support between peers, limited access to technology (including internet), language and cultural issues and poor academic support of parents [4]. Additionally the perceived role of the teacher in the rural areas implies a closer work with the community which could demand more physical and psychological demands in the daily work [33]. This situation often leads to the concentration of professionals in urban areas impacting on the quality of education and increasing inequalities between these two areas [34].

Most of the studies explored musculoskeletal disorders through self-reported questionnaires. Although this could have its limitations, Nordic Questionnaire has shown to be a good screening tool, especially in occupational settings. A study found a sensitivity of 100% and specificity of 88% to detect subjects with chronic or recurring low back pain for this questionnaire [17]. Additionally information about pain or discomfort during the last seven days could provide more reliable information minimizing memory recall bias. In this sense we may assume that this situation is not different in our study because teachers were able to understand these questions through their level of education, and fill it in a reliable way due to the anonymous report in the study.

Even though our study had 58% of response, it is within the expected percentage considering studies which focused in musculoskeletal disorders in schools teachers [2]. Nevertheless it is possible that teachers who did not want to participate in the study were those with greater workload and possibly those who may have presented less muscular disorders. Due to feasible reasons, we had to exclude schools with very difficult geographic access or with very few students, mainly located in the rural area (less than 15% from the total). Working conditions and in particular psychosocial factors at work could be a challenge for teachers working in those schools because perception of social, cultural, and professional isolation reported in teacher working in rural areas [35]. For that reason it is possible that the differences between rural and urban areas could be underestimated in our study.

Although prevalence of musculoskeletal disorders is considerable in school teachers in Chuquisaca, it is within the range reported previously. Teachers working in rural areas reported higher prevalence and more severe symptoms than teachers working in urban areas. It is needed to explore in-depth risk factors related to musculoskeletal disorders in this occupational group in order to propose appropriate strategies to control and reduce it. In the same way, it is important to consider surveillance systems in working conditions which include musculoskeletal disorders in teachers.