How to Use Biomechanical Job Exposure Matrices with Job History to Access Work Exposure for Musculoskeletal Disorders? Application of Mathematical Modeling in Severe Knee Pain in the Constances Cohort

Abstract

Introduction: Musculoskeletal disorders related to work might be caused by the cumulative effect of occupational exposures during working life. We aimed to develop a new model which allows to compare the accuracy of duration of work and intensity/frequency associations in application to severe knee pain. Methods: From the CONSTANCES cohort, 62,620 subjects who were working at inclusion and coded were included in the study. The biomechanical job exposure matrix “JEM Constances” was used to assess the intensity/frequency of heavy lifting and kneeling/squatting at work together with work history to characterize the association between occupational exposure and severe knee pain. An innovative model G was developed and evaluated, allowing to compare the accuracy of duration of work and intensity/frequency associations. Results: The mean age was 49 years at inception with 46 percent of women. The G model developed was slightly better than regular models. Among the men subgroup, odds ratios of the highest quartile for the duration and low intensity were not significant for both exposures, whereas intensity/duration were for every duration. Results in women were less interpretable. Conclusions: Though higher duration increased strength of association with severe knee pain, intensity/frequency were important predictors among men. Exposure estimation along working history should have emphasis on such parameters, though other outcomes should be studied and have a focus on women.

Occupational Risk Factors by Sectors: An Observational Study of 20,000 Workers

“…Furthermore, many workers within the public administration sector engage in desk-based tasks, such as typing, writing, or reading, which reduce the physical demands placed on the body. Work situations exposed to biomechanical factors are known to play a role in the appearance of musculoskeletal disorders [ 29 ], which are the main sources of work-related morbidity [ 30 ], and in the loss of productivity [ 31 , 32 ]. This study supports the importance of controlling these exposures through the installation of suitable equipment and tools, taking action in the workplace, and adapting the workstation if necessary [ 33 ].…”