Effect of Load Weight and Starting Height on the Variability of Trunk Kinematics

Abstract

Trunk kinematic variables have been used to understand the risk of low back injuries in the workplace. Variability in trunk kinematics has not been explored to the same level. In the current study, it was hypothesized that workplace variables (starting height and load weight) would have an impact on the variability in the kinematic variables describing trunk motion. Ten participants performed a repetitive lifting task under four different conditions representing two levels of load weight and starting height. The Lumbar Motion Monitor was used to capture key trunk kinematic variables from the concentric range of lifting motion. The dominant parameter in this experiment was found to be the starting height of the lift which significantly affected the variability of trunk kinematics in sagittal plane. In the transverse plane neither starting height of the load nor the weight of the load were found to influence the variability of trunk kinematics significantly.

Enhancing the Revised NIOSH Lifting Equation using ComputerVision

“…Direct measurement tools have been developed to measure trunk kinematics by placing sensors directly on the subject. For example, the lumbar motion monitor (LMM), an exoskeleton worn on the workers' shoulders and hips, has been used as an instrument for measuring trunk motion in research settings (Marras et al, 1992), and many studies have used it to collect trunk motion data for assessing the risk of LBP (Ferguson et al, 2011;Norasi et al, 2018). However, the usage of LMM in the workplace has been limited due to the cost, training, and required expertise (Patrazi et al, 2016).…”

Estimating Trunk Angle Kinematics During Lifting Using a Computationally Efficient Computer Vision Method

“…The LMM is an exoskeleton of the spine attached to the shoulder and hips using a harness, which has been found to provide reliable measurements of the position, velocity, and acceleration of the trunk (Marras et al, 1992). Many research studies have used LMMs for quantifying trunk kinematics as lifting risk factors (e.g., Ferguson et al, 2011; Lavender et al, 2017; Norasi et al, 2018). Efforts have been made to improve the wearability and usability of the direct measurement device for trunk motion to facilitate their application in the industry.…”