Potential of ultrasonography for epidemiological study of work-related wrist tenosynovitis.
OBJECTIVE: To explore the possible role of ultrasonography in case definitions for epidemiological studies of work-related wrist tenosynovitis. METHODS: Clinical and ultrasonography (7.5 MHz linear probe) data systematically collected from meat workers (n = 128) with biomechanical exposure characterisation were analysed. The diagnostic accuracy of different combinations of potentially relevant ultrasonography findings (nonhomogeneity, thickening and anechoic halo) was evaluated using symptomatology as a reference standard. The concordance between ultrasonography findings and symptoms was then analysed. RESULTS: Analysis of wrist biomechanical exposure was suggestive of increased prevalence of musculoskeletal disorders. Using symptoms as a reference standard, each of the three ultrasonography findings (and their combinations) showed good specificity (> or =85%) accompanied by low sensitivity (<60%); the positive likelihood ratio for at least two findings was 4.1. kappa Values (95% confidence intervals) between symptoms and different sets of ultrasonography findings were as follows: for non-homogeneity, kappa = 0.31 (0.19 to 0.43); at least one finding, kappa = 0.28 (0.16 to 0.40); at least two findings, kappa = 0.32 (0.20 to 0.44); all p<0.01. CONCLUSION: The use of ultrasonography in symptomatic subjects could contribute to a more specific epidemiological case definition of wrist tenosynovitis. The results of this study could help orient future research in this direction.