Differential effect of three types of exoskeletons and handling height on muscular activity, postural control and perceived effort during simulated bedside mobilization task

Abstract

Home care workers are affected by musculoskeletal disorders caused by biomechanical factors. This study investigated the effect of three exoskeletons devices (HAPO, HAPO FRONT and Japet.W) during load mobilization tasks at three bed heights in order to reduce physical risk factor. Anterior deltoid and longissimus bilateral muscular activities were recorded by EMG, a force platform was used to record center of pressure (CoP) displacement, and perceived exertion parameters were assessed using the Borg scale while nineteen healthy subjects performed a load manipulation. The use of the HAPO FRONT decreased global muscular activity by 5,6% and deltoid activity by 10,7%, exoskeletons reduced perceived effort, from 42% to 25%. Bed height has an inverse effect on deltoid and longissimus activity. These findings show that exoskeletons can reduce perceived effort and for overall and deltoids muscular activity. Therefore, the combination of shoulder and low back assistance appears as an interesting line of thought.

Keywords: Assistive device; Ergonomic intervention; Manual handling.