Evaluation of Thumb Joint Angles of Order Pickers

The thumb’s use is associated with musculoskeletal disorders in many sectors. It plays an essential role in the fulfillment of tasks such as holding. Unlike other upper limb joints, there are insufficient data on comfort angles of the thumb. The purpose of this study was to investigate the thumb joint angles for five order pickers with different anthropometric parameters. A three-dimensional motion analysis system was used with thirty reflective markers attached to each subject skin, allowing an optoelectronic system to track the path of different markers in 3Dimension. The participants performed nine actions such as rear traction, honk and lifting for seven different forklifts and two different movements of abduction/adduction and flexion/extension. As a result of this study, specific forklift type was found as the only type adapted for all participants with their different anthropometric parameters. While the other forklifts need some modifications to be adapted by others. This study can be extended with a larger number of participants working in the same field. The aim should be having a standard angle of the thumb’s comfort for order pickers.