Abstract

Objectives To identify the risk of hand-wrist disorders related to repetitive movements, use of hand force and wrist position in repetitive monotonous work. Methods Using questionnaires and clinical examinations, the prevalence and incidence of hand-wrist pain and possible extensor tendonitis (wrist pain and palpation tenderness) were determined in 3123 employees in 19 industrial settings. With the use of video recordings of work tasks individual measures for number of wrist movements, hand force requirements and wrist position were analysed both alone and in combination as risk factors for hand-wrist disorders controlling for potential personal and psychosocial confounders. All participants were re-examined three times during a follow-up period of approximately 3 years. Results Repetition, force and position were related to hand-wrist pain and possible tendonitis in the baseline analyses showing an exposure-response pattern. Odds ratios for the risk of possible tendonitis in the high exposure group were 2.4 (95% confidence intervals (CI) 1.1-5.1) for repetition, 2.3 (95% CI 1.1-5.0) for force, and 2.3 (95% CI 1.1-4.9) for position. Because of the strong correlation between these exposure characteristics the relative contribution of each factor could not be separated. The follow-up analyses confirmed the baseline findings for hand-wrist pain but no relationship was found for possible tendonitis (n=44). Conclusions Increasing levels of repetition, force and working with the wrist in non-neutral position were associated with prevalent hand-wrist pain and possible extensor tendonitis and were also risk factors for onset of hand pain. The effects of each of the physical factors could not be separated.