Anthropometry-corrected exposure modeling as a method to improve trunk posture assessment with a single inclinometer.
Measuring trunk posture in the workplace commonly involves subjective observation or self-report methods or the use of costly and time-consuming motion analysis systems (current gold standard). This work compared trunk inclination measurements using a simple data-logging inclinometer with trunk flexion measurements using a motion analysis system, and evaluated adding measures of subject anthropometry to exposure prediction models to improve the agreement between the two methods. Simulated lifting tasks (n=36) were performed by eight participants, and trunk postures were simultaneously measured with each method. There were significant differences between the two methods, with the inclinometer initially explaining 47% of the variance in the motion analysis measurements. However, adding one key anthropometric parameter (lower arm length) to the inclinometer-based trunk flexion prediction model reduced the differences between the two systems and accounted for 79% of the motion analysis method's variance. Although caution must be applied when generalizing lower-arm length as a correction factor, the overall strategy of anthropometric modeling is a novel contribution. In this lifting-based study, by accounting for subject anthropometry, a single, simple data-logging inclinometer shows promise for trunk posture measurement and may have utility in larger-scale field studies where similar types of tasks are performed.
School of Population and Public Health, University of British Columbia, Vancouver, Canada.
Robin
R
Van Driel
Catherine
C
Trask
Peter W
PW
Johnson
Jack P
JP
Callaghan
Mieke
M
Koehoorn
Kay
K
Teschke
D000293:Adolescent; D000328:Adult; D000886:Anthropometry / Q000295:instrumentation / Q000379:methods*; D053587:Arthrometry, Articular / Q000295:instrumentation*; D005542:Forearm / Q000033:anatomy & histology; D006801:Humans; D017770:Lifting; D008297:Male; D008954:Models, Biological; D009038:Motion; D011187:Posture; D013647:Task Performance and Analysis; D060726:Torso; D055815:Young Adult