Comparing upper arm and trunk kinematics between manufacturing workers performing predominantly cyclic and non-cyclic work tasks. (May 2021)

• Record Type: Journal Article
• Authors: Schall, Mark C.; Zhang, Xuanxuan; Chen, Howard; Gallagher, Sean; Fethke, Nathan B.
• Is Part Of: Applied ergonomics. Volume 93(2021)
• Publication Date: 2021-05
• Subjects: Musculoskeletal disorders -- Exposure variability -- Inertial measurement unit -- Posture -- Low back -- Shoulder; Human engineering -- Periodicals; 620.82
• DOI: 10.1016/j.apergo.2021.103356
• Languages: English
• ISSNs: 0003-6870

Abstract

Abstract: Musculoskeletal disorders (MSDs) are common among manufacturing workers. Exposure to non-neutral postures and high movement speeds associated with MSDs among manufacturing workers may depend on the extent of the variability in the work tasks performed (i.e., predominantly "cyclic" versus "non-cyclic" work). The objectives of this study were to (i) compare mean levels of full-shift exposure summary metrics based on both posture and movement speed between manufacturing workers performing predominantly cyclic (n = 18) and non-cyclic (n = 17) tasks, and (ii) explore patterns of between- and within-worker exposure variance and between-minute (within-shift) exposure level and variation within each group. Inertial sensors were used to measure exposures for up to 15 full shifts per participant. Results indicated (i) substantially higher upper arm and trunk movement speeds among workers performing predominantly cyclic tasks relative to workers performing non-cyclic tasks despite similar postures, and (ii) greater exposure variability both between and within workers in the non-cyclic group. Highlights: Upper arm and trunk kinematics of cyclic and non-cyclic manufacturing workers were compared. Movement speed exposure metrics were significantly different between groups. Working postures were similar between the two groups of workers. Greater exposure variability was measured between and within workers in the non-cyclic group.