Comparison among standard method, dedicated toolbox and kinematic-based approach in assessing risk of developing upper limb musculoskeletal disorders

Abstract

OCRA (Occupational Repetitive Action) index is one of the most used method for supporting risk assessment in tasks requiring manual handling of low loads at high frequency. One of the main drawbacks of this method is that the operator analyses the activities by observing videos. This kind of procedure is inherently not objective and operator-dependent. To overcome these limitations, we developed a toolbox to support the analysis with contextual noting and wearable sensors kinematic data. Three expert operators were asked to evaluate seven videos with and without the aid of the developed toolbox. Results underlined a high inter (R2 mean 0.4) and intra-operator variability (posture time percentage and technical actions (TAs) count mean errors respectively 7.44%, 4 TAs) when using the only video-based approaches. On the contrary, research outcomes showed that the introduction of wearable device allow to overcome these issues and to reduce noticeably the evaluation time (−98%).