RESUMEN
BACKGROUND: The upholstered furniture industry, the so-called "triangle of the sofa industry", is a geographic area of national and strategic economic importance in southern Italy. The single tasks are carried out mostly manually, with the characteristics of a handicraft approach. OBJECTIVES: The aim of the survey was to assess the prevalence of upper limb work-related musculoskeletal disorders (UL-WMSDs) in 30 factories of the sofa industry located in a large geographic area of the Puglia and Basilicata Regions. METHODS: In the period 1 January-31 December 2003 a network of occupational physicians investigated a population of 5.477 subjects (exposed n=3481, controls n=1996, M=3865, F=1612) in 30 different factories of the area. More than 60 percent of the total workforce studied was employed in large-sized companies (>500 employees). The following work tasks were considered: filling preparation workers, leather-cutting operators, sewing and upholstery-assembly workers. Case-definition was assessed through standardized procedures: symptoms by questionnaire plus physical and laboratory/imaging findings. RESULTS: Cumulative prevalence rates of UL-WMSDs as at 31 December 2003 reached values of up to 30% in high risk groups. Prevalence rates showed good correlation with the concise OCRA index used for assessment of exposure to repetitive strain and movements of the upper limb. The most frequently occurring disorders were tendon-related cysts and wrist tendonitis. Shoulder disorders were more frequent in male and female leather-cutting operators. CONCLUSIONS: This survey showed a significantly high prevalence of UL-WMSDs in sofa industry workers. It did not seem to be confirmed in this study that there was a greater female susceptibility to UL-WMSDs with the exception of carpal tunnel syndrome: gender difference seems to be less relevant at increasing levels of occupational exposure to repetitive movements and exertion of the upper limbs.