The relationship between the dominant hand and neck/shoulder pain in the workplace: a prospective cohort study.

Background: To date, no studies have investigated the relationship between one's dominant hand and neck/shoulder pain. The aim of this prospective cohort study is to explore the relationship between one's dominant hand and the severity of neck/shoulder pain. We also examined the relationship between the dominant hand and the onset of neck/shoulder pain at the follow-up among workers without neck/shoulder pain at baseline.

Methods: We conducted a prospective cohort study of 9,451 workers. The dominant hand is measured by ten items from the Japanese version of the Flanders Questionnaire at the baseline survey. We assessed neck/shoulder pain using a numeric rating scale. We calculated the unstandardized coefficient (B) using multiple regression analysis and the incidence rate ratio (IRR) for neck/shoulder pain using modified Poisson regression among workers who were free of neck/shoulder pain at baseline.

Results: Among the 9,451 respondents for the baseline survey, 6,156 responded to the follow-up survey (response rate: 65.1%). Mixed-handed workers report a higher degree of neck/shoulder pain than right-handed workers (B, 0.33; 95% CI, 0.09-0.58). Among 2,481 participants, mixed-handed workers also had a higher IRR for neck/shoulder pain (IRR, 1.27; 95% CI, 1.01-1.61). There was no difference in any of the left-handers compared with the right-handers.

Conclusions: The study found that mixed-handed workers had higher levels of neck/shoulder pain than right-handed workers, and the incidence rate was also higher among mixed-handed workers. Employers should consider these findings when designing work environments, managing tasks, and providing occupational health training to optimise worker comfort and safety.