Factors associated with musculoskeletal an postural discomfort of bus drivers

Abstract

Background: Sitting and driving for long hours can subject bus drivers' bodies to the stress of poor blood circulation and static muscle contractions. Body posture and workplace ergonomics influence musculoskeletal and discomfort. Consequently, musculoskeletal stress and inadequate posture increase muscle and joint overloads. Such factors contribute to the discomfort of these workers and increase their health problems. However, the factors associated with musculoskeletal pain and discomfort among bus drivers are insufficiently understood. The objectives of this study is to identify repetitive and forced postural changes, which cause musculoskeletal disorders, with bodily discomfort and worsening injuries and to detect incompatibilities between the anthropometry of drivers and the working environment of the bus, in addition to recommend preventive measures. Methods: Through an empirical and observational method, 65 drivers and 38 buses were surveyed, over four months in a bus transportation company in Bel em, State of Par a, Brazil. Ergonomics of the cabin features and techniques to assess postural discomfort have been implemented; Measurements of the vehicle cabin were made for the conformity evaluation to the Brazilian standards; Interviews with drivers to survey their socio-ergonomic profile and complaints about health problems; Questionnaire, performed after the drivers' working day, using Corlett and Bishop's body part discomfort scale to assess the interviewee's direct experience of discomfort in different body parts. Results: The profile of drivers, most of them are over 50 years old and have more than 6 years in the occupation, and with frequent long time shifts and overtime, can explain tiredness and discomfort. The lower back region is the most prevalent for discomfort level. Repetitive and forced postural changes were observed, performed in an almost fixed position in the sitting posture. The permanent musculoskeletal disorder arises from this longlasting static sitting posture between the seat and the steering wheel. Conclusion: Findings reveal that ergonomic layout of the cabin features could be improved by ergonomic changes in the design. Psychological and physical stresses characterize bus driving conditions and fatigue, overwork, and traffic environments, which contributed greatly to the symptoms observed and the respective diseases. Twenty six percent of bus drivers who participated in the study are burdened with musculoskeletal pain and discomfort that could eventually lead to the development of musculoskeletal disorders. Henceforth, ergonomic changes are recommended for posture adjustment and maintaining the driver vigilant for long working hours, including simple adjustments, such as instructing the driver to take more frequent breaks. Keywords: Musculoskeletal disorder(s). Bus drivers. Ergonomic features.