Work-related musculoskeletal disorders (WMSDs) represent one of the major issues concerning the occupational safety and health of workers. Thus, a reliable evaluation of workers' exposure to the risk factors that may contribute to WMSDs development is mandatory, above all, within an industrial context. At present, standard synthetic indices are widely used in this frame, presenting - however - several limitations due to poor reliability and time efficiency. The aim of this work was to investigate the contribution of the displacement quantified for each single joint during the execution of simple reaching tasks, to the overall discomfort of the worker evaluated by means of standard observational methods. Forty-five healthy volunteers were included in the analysis; each subject was asked to reach and rotate 2 spheres placed on a custom-made rack in standardized positions, i.e., above the head and one at floor level at centre side. Whole-body kinematics was acquired via a system based on wearable inertial measurement units. Standard ergonomic scales including RULA (Rapid Upper Limb Assessment), REBA (Rapid Entire Body Assessment), and MMGA (Method for Movement and Gesture Assessment), were assessed for each subject and each sphere position. Moreover, a quantitative index based on actual joint kinematics, i.e., W1 index, was computed for each joint angle involved in the task. Correlation analysis was performed for W1 relative to each joint with respect to RULA, REBA, and MMGA scores. Considering REBA and MMGA scores, the most comfortable reaching areas were the ones in which the sphere was positioned at the top; in contrast, the lowest positions evidenced the most increased discomfort indexes. The RULA did not result sensitive to the different positions, while REBA and MMGA seemed to be more influenced by the range of motion of the lower limb joint angles than the upper limb ones. This study underlines the necessity to focus on multiple potential contributors to WMSDs and underlines the importance of subject-specific approaches toward risk assessment by exploiting quantitative measurements and wearable technologies, which indeed represent key enabling approaches even in consideration of the novel “Industry 5.0” perspective.
Quantifying the contribution of single joint kinematics to the overall ergonomic discomfort
Scalona E.
;Rossetto G.;Mosso M.;Lopomo N. F.
2023-01-01
Abstract
Work-related musculoskeletal disorders (WMSDs) represent one of the major issues concerning the occupational safety and health of workers. Thus, a reliable evaluation of workers' exposure to the risk factors that may contribute to WMSDs development is mandatory, above all, within an industrial context. At present, standard synthetic indices are widely used in this frame, presenting - however - several limitations due to poor reliability and time efficiency. The aim of this work was to investigate the contribution of the displacement quantified for each single joint during the execution of simple reaching tasks, to the overall discomfort of the worker evaluated by means of standard observational methods. Forty-five healthy volunteers were included in the analysis; each subject was asked to reach and rotate 2 spheres placed on a custom-made rack in standardized positions, i.e., above the head and one at floor level at centre side. Whole-body kinematics was acquired via a system based on wearable inertial measurement units. Standard ergonomic scales including RULA (Rapid Upper Limb Assessment), REBA (Rapid Entire Body Assessment), and MMGA (Method for Movement and Gesture Assessment), were assessed for each subject and each sphere position. Moreover, a quantitative index based on actual joint kinematics, i.e., W1 index, was computed for each joint angle involved in the task. Correlation analysis was performed for W1 relative to each joint with respect to RULA, REBA, and MMGA scores. Considering REBA and MMGA scores, the most comfortable reaching areas were the ones in which the sphere was positioned at the top; in contrast, the lowest positions evidenced the most increased discomfort indexes. The RULA did not result sensitive to the different positions, while REBA and MMGA seemed to be more influenced by the range of motion of the lower limb joint angles than the upper limb ones. This study underlines the necessity to focus on multiple potential contributors to WMSDs and underlines the importance of subject-specific approaches toward risk assessment by exploiting quantitative measurements and wearable technologies, which indeed represent key enabling approaches even in consideration of the novel “Industry 5.0” perspective.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
