Assessing the exposure of street sweeping and potential risk factors for developing musculoskeletal disorders and related disabilities: a cross-sectional study

OBJECTIVE This study aims to assess the exposure of those involved in street sweeping to the development of musculoskeletal disorders (MSDs) and related disabilities and tries to identify the individual risk factors thereof. DESIGN A cross-sectional survey was conducted among street sweepers together with a comparison group. A modified Standardized Nordic Questionnaire was adopted to measure the prevalence of MSDs and related disabilities. The impact of the occupation of sweeping on the development of MSDs and related disabilities was assessed using the propensity score matching (PSM) method. A multivariate logistic regression model was employed to identify the individual risk factors. PARTICIPANTS Street sweepers (n=180) and a comparison group (n=180), working for at least a year as formal employees of the Municipal Corporation of Greater Mumbai (MCGM), were randomly selected from 6 municipal wards. RESULTS The prevalence of the MSDs was significantly higher among the sweepers for shoulders (32%), wrists/hands (29%), elbows (27%) and neck (17%) compared with the comparison group, in which the prevalence was 11%, 19%, 9% and 11%, respectively. The disabilities too were significantly higher among the street sweepers for the lower back (27%), upper back (27%), wrists/hands (26%), shoulders (24%) and elbows (23%) compared with the comparison group, for which the figures were 18%, 19%, 13%, 9% and 6% respectively. The PSM method highlighted that the occupation of sweeping raised the risk of developing MSDs and disabilities particularly for the shoulders (17-16%), wrists/hands (14% each), elbows (13% each) and the upper back (12-13%). After adjusting the age, body mass index and the caste of the street sweepers, the number of years of engagement in street sweeping and the location of work emerged as potential risk factors in the development of MSDs and, thereby, related disabilities. CONCLUSIONS The study concluded that the occupation of street sweeping raises the risk of MSDs and related disabilities. This study recommends preventive and curative measures to deal with MSDs among street sweepers.