Description |
Lifting heavy loads is a major concern for workers and employers as it may contribute to low back pain (LBP). Although a workstation may be ergonomically abated so as to reduce lifting, it is not reasonable to completely eliminate all lifting from some jobs. For this reason, a great deal of work has been done to study the biomechanics of different lifting techniques. More recently, in an effort to reduce the risk involved with lifting, new technology is emerging that aids with human-powered lifting. A Lift Assist Device (LAD) is a mechanical aid that supports some of the forces or torques during lifting, by transferring them to an area with a lower risk of injury. The main objective of this study was to investigate the effectiveness of LAD designs, and identify key features to be incorporated into future LAD designs. Ten healthy male participants tested 36 combinations of four LAD conditions (three different designs and nonassisted), at three different speeds (slow, medium, fast), and with three twisting conditions (left, forward, right). The LAD designs included three unique methods for generating torque, two prototypes, and one commercially available device. Many statistically significant (p<0.05) differences between devices and between lifting postures were identified. These differences were examined to show strengths and weaknesses in the effect of each LAD. This information may be useful when choosing a specific type of LAD for a particular job and when considering future designs for LADs. |