|Year : 2022 | Volume
| Issue : 3 | Page : 193-197
Work related musculoskeletal disorders among bus conductors of Udupi District, Karnataka
Garima Verma1, Rajnarayan R Tiwari2
1 Department of Public Health, MPH Scholar, Prasanna School of Public Health, Manipal, Karnataka, India
2 Department of Environmental Epidemiology, ICMR-National Institute for Research in Environmental Health, Bhopal, Madhya Pradesh, India
|Date of Submission||30-Oct-2021|
|Date of Decision||25-Mar-2022|
|Date of Acceptance||03-Apr-2022|
|Date of Web Publication||26-Sep-2022|
Dr. Rajnarayan R Tiwari
ICMR-National Institute for Research in Environmental Health, Bhopal Bypass Road, Bhauri, Bhopal - 462030, Madhya Pradesh
Source of Support: None, Conflict of Interest: None
Background: Government bus conductors are at high risk for work-related musculoskeletal disorders (MSDs) due to the work environment and work conditions. Thus, the present study was undertaken to assess the prevalence and associated factors of musculoskeletal problems among bus conductors. Materials and Methods: This cross-sectional study included 237 bus conductors of government bus depots. The data were collected by interview technique on a structured questionnaire. Self-reported musculoskeletal pain over the last 12 months was the case definition. Results: The present study revealed that 62.4% of bus conductors had musculoskeletal pain. The multivariate analysis suggested that tobacco smoking, overweight or obesity, and lack of enough breaks during work were significant risk factors for the occurrence of musculoskeletal pain in study participants. Conclusion: Thus, to conclude, the conductors are at risk of musculoskeletal problems, which can be attributed to occupational as well as non-occupational factors.
Keywords: Conductors, obesity, vibration, WMSDs
|How to cite this article:|
Verma G, Tiwari RR. Work related musculoskeletal disorders among bus conductors of Udupi District, Karnataka. Indian J Occup Environ Med 2022;26:193-7
|How to cite this URL:|
Verma G, Tiwari RR. Work related musculoskeletal disorders among bus conductors of Udupi District, Karnataka. Indian J Occup Environ Med [serial online] 2022 [cited 2022 Dec 7];26:193-7. Available from: https://www.ijoem.com/text.asp?2022/26/3/193/357024
| Introduction|| |
Musculoskeletal disorders (MSDs) are a significant cause of physical limitation affecting humans around the globe. MSDs can cause severe physical impairment, pain, and can greatly alter the psychosocial status of the affected individual. In 2016, the Global Burden of Disease study reported that MSDs were the second most common cause of disability worldwide, with back pain as the leading cause. Approximately 20–30% of people worldwide live with a musculoskeletal condition.
Work-related musculoskeletal disorders (WMSDs) develop in the musculoskeletal system over a prolonged period and may limit activities in the professional environment or non-professional activities., The WMSDs also have significant medical, economic, and social impacts in terms of absence due to sickness, cost of medical care, lost production, and personal suffering.
The prolonged sitting or standing posture during long-distance driving and the whole-body vibration from poorly maintained vehicles increases the vulnerability of professional drivers to developing MSDs.,,, In addition, non-occupational factors such as age, gender, smoking habit, obesity, and general health status are associated with work-related musculoskeletal ailments among drivers. Similarly, prolonged standing is related to lower extremity musculoskeletal symptoms through blood pooling. The prolonged standing has also been linked to changes in discomfort and cognitive function, along with muscle fatigue, movement, lower limb swelling, and mental state.
In India, a government transport bus is controlled by a driver and a conductor. The conductor issues tickets to the passengers through handheld equipment. The conductors work in three shifts with a leave per week. Though one seat is reserved for the conductor; however, he seldom gets time to sit due to the often-overcrowded bus and he has to issue tickets to every passenger. The buses are often old and poorly maintained thereby increasing the vibration. The poor road conditions such as roads having potholes and mud roads having uneven surfaces further aggravate the exposure.
Though several studies have been carried out on MSDs among passengers traveling in such vehicles, the study among conductors is not available., Thus, the present study was undertaken among conductors of government buses to assess the prevalence of MSDs and find the occupational, environmental, and non-occupational factors associated with it.
| Materials and Methods|| |
This cross-sectional study was conducted among long-distance government bus conductors (more than 500 km/day) in Udupi District. The conductors on leave for more than 3 months or on office duties were excluded. In total, 237 conductors were randomly selected from the selected depot and fulfilled inclusion criteria. The study was approved by the Institutional Ethics Committee of Kasturba Medical College, Manipal (IEC140/2014).
After obtaining written informed consent, the data collection was done on a predesigned and semi-structured questionnaire by direct interview of the conductors. The questionnaire in vernacular language was validated through a pilot study and the reliability of the questionnaire was found to be good (Cronbach's alpha = 0.798). The assessment of musculoskeletal pain was done using a modified Nordic questionnaire.
Self-reported pain in any of the joints over the last 12 months was considered the operational definition of MSD. The occupational factors included working years, daily working hours, the shift of work, daily distance traveled, and breaks in between work, non-occupational factors included age, presence or absence of a chronic condition, physical activity, Body Mass Index (BMI), tobacco smoking, tobacco chewing, alcohol drinking, whereas environmental factors included bus type, maintenance condition of the bus, driving speed, self-reported exposure to whole-body vibration and self-reported road condition.
The observational data were collected from the participants during work. The Rapid Entire Body Assessment (REBA) scale was used to do a postural analysis of those reporting WMSDs. The total traveling time on the bus was about 10–15 min. After observing the conductor for 5 min, the most frequent posture was used for scoring. On the basis of score, the participants were classified in to five groups namely “No risk” (score = 1), “Low risk” (scores = 2-3), “Medium risk” (scores = 4–7), “High risk” (scores = 8–10) and, “Very high risk” (scores > 11).
The statistical analysis was done using SPSS version 24.0. The descriptive variables were presented in percentages. The association of different factors with the presence of musculoskeletal pain was assessed using the Chi-square test and Odds ratio (OR) with their 95% confidence intervals (CI), whereas the interactive effect of multiple factors was done through multivariate analysis.
| Results|| |
All bus conductors included in the study were male. The mean age was 42.53 ± 8.95 years, the majority were married, studied until pre-university college (78.7%), and were having monthly salaries between Rs 10,000 and 20,000 (73.1%).
Based on the operational definition, 148 (62.4%) participants had musculoskeletal pain. [Table 1] shows the characteristics of these MSDs. It can be observed that the lower back (27.4%) and knees (31.6%) were the most common joints affected by pain.
[Table 2] depicts the distribution of overall musculoskeletal pain according to the study variables. More proportion of those in the job for ≥10 years (P = 0.03), smokers (P = 0.04), travelling lesser distances daily (P = 0.03), overweight or obese (P = 0.02), and taking lesser breaks in between work (P = 0.04) had musculoskeletal problems.
|Table 2: Distribution of musculoskeletal pain among participants according to the study variables|
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The univariate and multivariate analysis of MSDs according to study variables is depicted in [Table 3]. On univariate analysis, the employment duration for ≥10 years (odds ratio [OR] = 1.86; 95% confidence interval [CI]: 1.07–3.21), tobacco smoking (OR = 1,86; 95% CI: 1.03–3.37), higher BMI (OR = 1.99; 95% CI: 1.13–3.53), and less than two breaks between work (OR = 1.75; 95% CI: 1.03–2.97) were significant risk factors, whereas on multivariate analysis all except employment duration for ≥10 years was found to be statistically significant.
|Table 3: Multiple logistic regression for musculoskeletal pain and study variables|
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The REBA analysis revealed that 34.7% were having no risk, 6.3% had low risk, 35.7% had medium risk, 15.1% had high risk, and only 5.5% had a very high risk of developing WMSDs with respect to the awkward posture they adopt during their work.
| Discussion|| |
The present study found that 62.4% of bus conductors had musculoskeletal pain. The commonly affected regions were the knee joints and lower back. These being the most weight-bearing joints are more liable to the insults of awkward posture, heavy lifting, and whole-body vibration. An earlier study also reported problems in knees (83.3%), and back areas (56.7%) in the past 1 year; however, the prevalence was found to be more than in the present study.
Significantly more participants who were in the job for ≥10 years had musculoskeletal pain, which may be due to cumulative musculoskeletal trauma. Further, a significantly more proportion of younger workers (<40 years) and those working continuously (taking <2 breaks) during working hours had musculoskeletal pain. Smoking could theoretically be a risk factor for developing chronic pain due to the nicotine, which increases the degradation of collagen, and decreases blood and oxygen supply, resulting in vascular damage predisposing to back pain.
It was also observed that a higher proportion of obese or overweight bus conductors had musculoskeletal pain. As reported earlier, there is a strong bidirectional relationship between obesity and musculoskeletal pain. This can further be explained by the fact that reduction of weight mainly through increased physical activity is advocated for managing and preventing MSDs. The prevalent obesity can be partly attributed to unhealthy food habits, effects of change in circadian rhythm in those working in night shift, and lack of physical activity. Those working continuously were more susceptible to developing musculoskeletal pain, which can be attributed to the overuse of musculoskeletal tissues as reported in the earlier studies.
The multivariate analysis suggested that tobacco smoking, overweight or obesity, driving more distances per day, and lack of enough breaks during work were significant risk factors for the occurrence of musculoskeletal pain.
When compared with BMI, the REBA scores were found to have a direct relation to BMI as reported in an earlier study. Further, a very strong association was found between higher REBA scores and the occurrence of musculoskeletal symptoms (χ2 = 162; df = 3, P < 0.01).
The limitation of the study includes the non-measurement of actual vibrations generated and transmitted through the bodies of conductors due to non-feasibility issues. Though most of the driving environmental conditions were self-reported some of which were substantiated through observation by the investigators. Nevertheless, the study highlights the issue that conductors are equally vulnerable to musculoskeletal pain while at work due to exposure to several occupational, non-occupational, and environmental factors.
The conductors are at risk of musculoskeletal pain, which can be attributed to a repetitive strain injury, vibrations, long hours of traveling, tobacco smoking, and physical inactivity. Thus, ergonomic practices such as comfortable seating with sufficient back support, automatic electronic ticket issuing systems to ensure reduced time spent on standing, regular physical activity such as stretching and bending exercises, yoga, and better work organization such as splitting the shifts could benefit these conductors.
The investigators would like to express their genuine and sincere gratitude to the Department of Public Health and Administration department of Manipal University, Manipal. The support and help provided by supervisors and the supporting staff of bus depots are also acknowledged.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Brooks PM. The burden of musculoskeletal disease-a global perspective. Clin Rheumatol 2006;25:778-81.
Vos T, Abajobir AA, Abate KH, Abbafati C, AbbasKM, Abd-Allah F, et al
. Global, regional and national incidence, prevalence and years lived with disability for 328 diseases and injuries for 195 countries, 1990-2016: Asystematic analysis for the Global Burden of Disease Study 2016. Lancet 2017;390:1211-59.
Baldwin ML, Butler RJ. Upper extremity disorders in the workplace: Costs and outcomes beyond the first return to work. J Occup Rehabil 2006;16:303-23.
Latko WA, Armstrong TJ, Franzblau A, Ulin SS, Werner RA, Albers JW. Cross-sectional study of the relationship between repetitive work and the prevalence of upper limb musculoskeletal disorders. Am J Ind Med 1999;36:248-59.
Werner RA, Franzblau A, Gell N, Ulin SS, Armstrong TJ. Predictors of upper extremity discomfort: A longitudinal study of industrial and clerical workers. J Occup Rehabil 2005;15:27-35.
Kasemsan A, Joseph L, Paungmali A, Sitilertpisan P, Pirunsan U. Prevalence of musculoskeletal pain and associated disability among professional bus drivers: Across-sectional study. Int Arch Occup Environ Health 2021;94:1263-70.
Szeto GP, Lam P. Work-related musculoskeletal disorders in urban bus drivers of Hong Kong. J Occup Rehabil. 2007;17:181-98.
Hulshof CT, Verbeek JH, BraamITJ, Bovenzi M, van Dijk FJH. Evaluation of an occupational health intervention programme on whole-body vibration in forklift truck drivers: Acontrolled trial. Occup Environ Med 2006;63:461-8.
Chen JC, Chang WR, Chang W, Christiani D. Occupational factors associated with low back pain in urban taxi drivers. Occup Med 2005;55:535-40.
Coenen P, Parry S, Willenberg L, Shi JW, Romero L, Blackwood DM, et al
. Associations of prolonged standing with musculoskeletal symptoms-A systematic review of laboratory studies. Gait Posture 2017;58:310-8.
Baker R, Coenen P, Howie E, Lee J, Williamson A, Straker L. A detailed description of the short-term musculoskeletal and cognitive effects of prolonged standing for office computer work. Ergonomics 2018;61:877-90.
Araújo AV, Arcanjo GS, Fernandes H, Arcanjo GS. Ergonomic work analysis: A case study of bus drivers in the private collective transportation sector. Work 2018;60:41-7.
Wibowo RKK, Soekarno S, Syuhri A, Vayendra DD. Analysis and design of bus chair for economic class using ergonomic function deployment (EFD) method. Int J Adv Sci Res Eng 2018;4:161-7.
Crawford JO. The Nordic musculoskeletal questionnaire. Occup Med 2007;57:300-1.
Gangopadhyay S, Dev S, Das T, Ghoshal G, Ara T. An ergonomic study on the prevalence of musculoskeletal disorders among Indian bus conductors. Int J Occup Saf Ergon 2012;18:3-12.
Abate M, Vanni D, Pantalone A, Salini V. Cigarette smoking and musculoskeletal disorders. Muscles Ligaments Tendons J 2013;3:63-9.
Cameron AJ, Magliano DJ, Dunstan DW, Zimmet PZ, Hesketh K, Peeters A, et al
. A bi-directional relationship between obesity and health-related quality of life: Evidence from the longitudinal Aus Diab study. Int J Obes 2012;36:295-303.
Aicale R, Tarantino D, Maffulli N. Overuse injuries in sport: Acomprehensive overview. J Orthop Surg Res 2018;13:309.
Sethi J, Sandhu JS, Imbanathan V. Effect of body mass index on work related musculoskeletal discomfort and occupational stress of computer workers in developed ergonomic setup. Sports Med Arthrosc Rehabil Ther Technol 2011;3:22.
[Table 1], [Table 2], [Table 3]