Use of a prevention index to identify industries at high risk for work-related musculoskeletal disorders of the neck, back, and upper extremity in Washington state, 1990-1998.

BACKGROUND: The prevention of work-related musculoskeletal disorders such as carpal tunnel syndrome and low back disorders has been a focus of international prevention efforts including regulation. This study examines workers compensation claims in Washington State to provide baseline data from which to assess the need and the effects of prevention activities.

METHODS: Washington State Fund workers compensation claims for general and selected specific hand/wrist, elbow, shoulder, and back disorders in 1990-1998 as well as general self-insured compensable (four or more lost workdays) claims data were examined. Payroll hours were used to calculate claims incidence rates per 10,000 full-time equivalent employees (FTEs). We created a prevention index (PI) to rank industries by averaging the ranks of their number of claims and their claims incidence rate. The focus was on non-traumatic soft tissue musculoskeletal disorders (NTST-MSDs).

RESULTS: Between 1990-1998, there were 392,925 State Fund accepted claims for NTST-MSDs of the neck, back, and upper extremity resulting in $2.6 billion in direct costs and 20.5 million lost workdays. The average claims incidence rate (CIR) was 355 NTST-MSDs per 10,000 FTEs. The NTST-MSD CIR decreased significantly less than that for all other claims (P = 0.05) but the CIR for upper extremity NTST-MSDs did not significantly decrease over the study period. There were no significant changes in the CIRs for sciatica (4.9 per 10,000 FTEs) and rotator cuff syndrome (15.3 per 10,000 FTEs), whereas the CIR for epicondylitis (10.6 per 10,000 FTEs) increased and for carpal tunnel syndrome (24.5 per 10,000 FTEs) decreased significantly over the study period. Based on the prevention index, the top five industries for combined State Fund and Self-Insured Compensable NTST-MSDs were Trucking and Courier Services (SIC 421), Nursing Homes (SIC 805), Masonry (SIC 174), Air Transportation (SIC 451), and Residential Construction (SIC 152). Using Washington Industrial Classes (WIC), temporary workers in assembly and administrative services were also high on the prevention index.

CONCLUSIONS: NTST-MSDs continue to be a large and costly problem in Washington State. While the incidence rates for some NTST-MSDs are decreasing, the overall rate is not decreasing as fast as the rate for all other claims. In some cases, the rate is stable (sciatica, rotator cuff syndrome) or increasing (epicondylitis). Heavy manual handling and repetitive work characterize the industries with the highest risk.