[Lumbar biomechanical risk factors due to manual handling of loads in the distribution of meat products].

Introduction: Identify risk factors for lumbar musculoskeletal disorders (MSD) associated with manual handling (MHL) of meat products in truck loading and unloading activities.

Method: Cross-sectional descriptive observational study with a mixed approach, based on ergonomic analysis of work activity. The 4 workers from the loader and loader-driver positions participated. Kinematic and dynamometric analyzes were performed to determine compression and shear forces and musculoskeletal risk in the lumbar area. Interviews and observations were conducted to analyze tasks and determine the times involved in each operation, type of exposure and the determinants of work activity.

Results: The work context is highly variable during the loading and unloading of the truck, considering the variability at each delivery point the characteristics of the parking lots, weather conditions, the presence of animals and other obstacles during manual transport of the load. The MHL produces forces over 4000 N of disc compression at levels L4-L5 and L5-S1, the initial push and pull forces were 51.2 kg*f and 27.3 kg*f respectively, which shows the risk of MSD. The work activity is determined by the type of working day, the organization of the distribution and the lack of mechanical means to support the loading and unloading of trucks.

Conclusions: The manual handling tasks in this industry are physically very demanding and improving these working conditions represents a significant challenge for prevention.