Work-related upper limb musculoskeletal disorders (WRULMSDS) risk assessment: different tools, different results!: What are we measuring?

Abstract

Several methods may be used for Work-Related Upper Limbs Musculoskeletal Disorders (WRULMSDs) risk assessment. We compare different methods and their results at the same workplace trying to increase a more accurate WRULMSDs risk assessment based at the hazard identification. This study took place at an automotive plant and included all the workstations (n=366) which has been previously studied with OCRA checklist. The methodology included the re-application of OCRA checklist at all workstations with scores OCRA ≥16,5 (n=152). At workplaces with high risk (n=71) we also applied three other methods of «risk evaluation»: (a) Rapid Upper Limb Assessment; (b) Strain Index; and (c) Hand Activity Level. Work activity has been also videotaped and the main risk factors were analyzed. The analysis is focused on the right upper limb. Outcomes were different with the use of each method, notably, they show disagreement in the categorization of high-risk workstations. So, (a) OCRA has a moderate correlation (p<0,001) with SI (rSp=0,52) and with (b) HAL (rSp=0,42); (c) HAL has a strong correlation with SI (rSp =0,77) and (d) RULA scores are not correlated with the others methods. OCRA, SI, RULA and HAL show evidence of distinct risk results that confirm the need of a selection criterion. The knowing of witch risk factors are presents at each workstation permit the selection of the most accurate method. Different WRULMSD’s risk assessment results will influence risk management and just with a workstation rigorous knowledge and the consequent method selection criterion, the process may be more effective.

Keywords

• work-related upper limbs
• musculoskeletal disorders (wrulmsds)
• occupational risk assessment
• wrulmsds observational risk assessment