The Strain Index and TLV for HAL: Risk of lateral epicondylitis in a prospective cohort
Background This study's objective was to quantify exposure-response relationships between job physical exposure (JPE) and incidence of lateral epicondylitis (LE).
Methods A cohort of 536 workers was enrolled from 10 manufacturing facilities and followed monthly for 6 years to ascertain changes in JPE and health status. JPE was individually measured and quantified using the Strain Index (SI) and TLV for HAL. Worker demographics, medical history, psychosocial factors, and current musculoskeletal disorders were obtained.
Results Fifty-six workers developed LE. In multivariate models JPE, age, family problems, and swimming were associated with increased risk of LE. SI showed an exposure-response relationship with maximum hazard ratio (HR) of 4.5(P = 0.04). TLV for HAL showed a non-statistically significant trend for increased risk of LE (P = 0.19).
Conclusion JPE is associated with increased risk of LE. The SI and TLV for HAL are useful metrics for estimating JPE.