Musculoskeletal problems among workers of an Iranian ...

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Original Article

Musculoskeletal problems among workers of an Iranian communication company Abstract

Th a is si P te D ho F st is ed av by aila m Me ble ed dk fo kn no r f ow w ree .c Pu d om b ow ). lica nlo tio a ns d f (w rom w w.

Introduction: Work-related musculoskeletal disorders (WMSDs) are a common health problem throughout the world and a major cause of disability in the workplace. Awkward working posture is a main risk factor for developing WMSDs. Assessment of exposure level to WMSDs risks can be an appropriate base for planning and implementing interventional ergonomics program in the workplace. This study was conducted among workers of an Iranian communication company with the objectives of a) determination of WMSDs prevalence and b) assessment of exposure level to WMSDs risks. Materials and Methods: In this cross-sectional study, 85 randomly selected workers from assembly line and closed circuit TV (CCTV) participated. Nordic musculoskeletal questionnaire (NMQ) was used to study prevalence of WMSDs and rapid upper limb assessment (RULA) technique was applied to assess physical exposure to the risks. Results: The results of NMQ revealed that WMSDs occurred at an high rate. The highest rates of WMSDs prevalence were reported in shoulders (73%), knees (67.1%) and back (66.7%). RULA showed that the Grand Score of 88.1% of cases were high and very high (action levels 3 and 4). Significant association was found between risk level and musculoskeletal symptoms in lower back (P0.05).

Upon completion of the field survey, collected data were transferred into the computer for statistical analysis. Statistical analyses were performed using SPSS (Ver. 13). Independent t-test, chi-square and Mann-Whitney tests were used to assess associations between personal and work variables with reported musculoskeletal symptoms.

Table 3 presents the results of assessment of physical exposure to work-related musculoskeletal risks. As shown in Table 3: a) in no cases, action level was 1. b) in 11.7% of the workers studied, RULA Grand Score was between 3 and 4 indicating that the level of exposure to musculoskeletal risks needed considering (action level 2). c) in 75.2% of the workers studied, RULA Grand Score was between 5 and 6 indicating that the level of exposure to musculoskeletal risks was high and ergonomics intervention to decrease exposure level seemed essential (action level 3). d) in 12.9% of the workers studied, RULA Grand Score was 7 indicating that the level of exposure to musculoskeletal risks was very high and immediate ergonomics intervention to decrease exposure level seemed essential (action level 4).

Th a is si P te D ho F st is ed av by aila m Me ble ed dk fo kn no r f ow w ree .c Pu d om b ow ). lica nlo tio a ns d f (w rom w w.

Score was then calculated for each case. Consequently, the level of interventional action required to reduce the risks of musculoskeletal injury due to physical loading on the worker was determined.

RESULTS

Table 1 shows the mean and standard deviation of age and job tenure of the workers participated in the study. Table 2 presents the prevalence of MSDs symptoms in different body regions of the workers during the last 12 months. As Table 2 shows, the most commonly affected regions among the workers are shoulders (73%), knees (67.1%), lower back (66.7%), upper back (66.7%), wrists/hands (64.7%) and neck (64.7%).

Statistical analyses showed significant association between job tenure and reported musculoskeletal problems in knees and upper back (P0.05 >0.05 >0.05 >0.05 0.037 >0.05 >0.05 >0.05

*Mann-Whitney test

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Choobineh A, et al.: Musculoskeletal problems in communication industry

awkward posture of this region and lack of use of backrest while working. These implies that any interventional program for preventing or reducing musculoskeletal problems among the workers should focus on reducing physical exposure to the MSDs risk factors of these regions.

ACKNOWLEDGMENTS Funding through Shiraz University of Medical Sciences, Contract No. 84-2689, supported this study.

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The results also indicated that age was not significantly associated with musculoskeletal symptoms in different body regions. In some other studies, i.e., on ship building workers and VDT operators, the same result has been reported.[23-25] No association was found between sex and MSDs prevalence rate. Although it is in agreement with the results of other studies, [26,27] but many studies have showed association between sex and musculoskeletal symptoms.[28-30]

and neck. Redesigning workstations based on ergonomics principles were recommended.

3.

Based on the results of physical exposure to work-related musculoskeletal risks assessment by RULA, in 88.1% of the workers studied the level of exposure to musculoskeletal risks was high and very high (action level 3 and 4). This indicated that the jobs and working conditions in the assembly line and CCTV units were conducive for developing WMSDs. Therefore, ergonomics interventions seemed necessary to improve working conditions and decrease exposure level.

The results also demonstrated that there was a direct association between RULA risk level and prevalence rate of the reported symptoms in lower back with the significant association. This is in line with the findings of similar studies.[31,32]

Based on the results of RULA, awkward working postures and static work were found to be the major risk factors that the workers were encountered. Since the postural problems have been found to be largely caused by improperly designed and ill-arranged workstation furniture,[33] reducing the RULA Grand Score via redesigning workstations was strongly recommended. Regarding this, the following corrective measures could be taken into consideration for reducing exposure level and consequently preventing WMSDs in this company: a) Reducing the height of tables in accordance to the workers’ anthropometric characteristics. b) Using seats with appropriate backrest in the workstation. c) Designing sitting-standing workstations to avoid posture fixation. d) Conducting workers training program on working posture. e) Devising an appropriate work-rest cycle. Based on the findings, it was concluded that WMSDs occurred in high rate in this company. Workers’ level of exposure to WMSDs risks was high. Taking corrective measures for reducing risk level into consideration seemed essential. Any ergonomics intervention program in the workplace should be focused on eliminating awkward postures of shoulders, back 35

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Source of Support: Shiraz University of Medical Sciences, Conflict of Interest: None declared.

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There is no data on follow-up of these patients. Authors’ Reply: The follow up of patients have been included in the results section [Page 3, para 2] Authors should highlight the relation of complication to duration of diabetes. Authors’ Reply: The complications as seen in our study group has been included in the results section [Page 4, Table]

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