Medical care surrounding work-related back injury claims among Washington State Union Carpenters, 1989-2003

Objective: We describe medical care received through workers' compensation (WC) and union-provided insurance surrounding work-related back injuries and examine relationships between care provided and time off work among a large cohort of carpenters. Methods and Participants: Union records identified a cohort of 20,642 carpenters working in Washington State from 1989-2003 and their private health insurance claims. These data were linked to workers' compensation files from this state-run program including records of medical care. Results: Over 74,000 WC medical encounters resulted from 2959 work-related back injuries. Eleven percent received private care for musculoskeletal back pain within 90 days of work-related injury; this proportion increased with increasing lost days. Delay to physical therapy was more prevalent among those out of work longest. The proportion of claimants with care from both systems and from private utilization only increased after the first 90 days and, for the subset with at least one paid lost work day, after return to work. Conclusions: Examination of medical care through both systems versus solely in workers' compensation provides a more complete understanding of back injury care while also demonstrating complexity. Differences in outcomes based upon treatment shortly after injury are worthy of further exploration.