An analytical study of musculoskeletal symptoms, demographic characteristics and physical work load among construction workers

Introduction: Physical workload is one of the main risk factors in developing of musculoskeletal disorders in construction workers. The current study was carried out to determine the prevalence of musculoskeletal disorders and its relationship with demographic characteristics and physical work load index (PWLI) in construction workers. Material and Methods: This investigation was a descriptive and cross-sectional study in which 162 subjects including 75 rebar and 87 bricklayer workers were participated. Nordic musculoskeletal and physical workload questionnaires were employed as the tools of this study. Chi-squared and logistic regression tests were used for statistical analysis in SPSS 21 software. Results: The mean of age and working experience of construction workers were 34.6 +/- 8.6 and 11.2 +/- 6.8 years, respectively. The most prevalent symptoms were in the body regions of upper back (57.4%), lower back (35.8%), and neck (30.2%). In the univariate analysis, the musculoskeletal symptoms of shoulders, low back, feet, knees, and thighs with PWLI and the upper back pain with age, working experience, and working hours had significant relationships (P<0.05). According to logistic regression analysis, with the increase of the value of PWLI to more than 90 percentile, the chance of having symptoms of musculoskeletal disorders in low back, knees, and feet and also with the increase of working hour to more than 8 hours, the chance of having symptoms in low back and feet increased significantly. Conclusion: The prevalence of musculoskeletal disorders was high in the studied construction workers. Most of the musculoskeletal symptoms were correlated with PWLI. Therefore, PWLI could be used to determine the construction jobs with the high risk of musculoskeletal disorders. To reduce the symptoms of musculoskeletal disorders in construction workers, the reduction of sources of physical workloads such as heavy material handling and awkward postures are proposed. It is also recommended that the working hours be limited to less than 8 hours.