BACKGROUND: There are few epidemiological data regarding musculoskeletal
disorders (MSDs) in retail industry. Biomechanical risk assessment in
ergonomics is commonly performed in retail sector using standardized
protocols. However, such protocols have numerous limitations, such as the
lack of objectivity or applicability and restrictive conditions.
OBJECTIVE: The aim of this study was to analyze one of the most commonly
used shelves in vegetable and fruit departments in order to investigate the
effect of different shelf levels (i.e. with variations in height and
horizontal distance) and load weights on the workers' biomechanical load.
METHODS: We investigated trunk, shoulder, elbow, hip, knee and ankle joint
ROMs, as well as the mean and peak EMG values of the upper limb, trunk and
lower limb muscles.
RESULTS: We found that shelf level has a significant effect on most of the
parameters examined, whereas within this limited range of 6 and 8 kg, weight
does not affect the biomechanical load. We also identified the shelf levels
that place the least and most strain on the musculoskeletal system.
CONCLUSIONS: We therefore recommend that the height and horizontal distance
be carefully considered when shelves are being designed. Kinematic and EMG
approach may help to objectively assess shelf-related risks. Our findings
are in agreement with RNLE LI values and therefore support RNLE.
