Deformity of fingers among woman workers at papermaking mill

With regard to deformity of the fingers (chiefly Heberden's nodes) frequently occurring in Japan among workers preparing school lunches, an epidemiological study was carried out with a suspicion that this deformity might be an occupational disease. We studied the deformity of fingers among woman employees of a papermaking mill (262 mill workers in comparison with 108 office workers) who excessively use their fingers on the job like workers preparing school lunches. The results of this study showed that the number of mill workers suffering from deformity of the fingers (chiefly Heberden's nodes) was significantly (p less than 0.01) greater than that of office workers. Genetic factor, aging factor and mechanical factor have been cited as the etiological factors for the development of Heberden's nodes. However, our findings suggest that mechanical factor is a more important rather than the genetic or aging factor. As for mechanical factor, we have proposed for the first time that repetition of strong and precise pinching movement with the use of all fingers of both hands is an important factor.