Outcome of surgery for thoracic outlet syndrome in Washington state workers' compensation.

OBJECTIVE

To determine the predictors of outcome of thoracic outlet syndrome (TOS) surgery in a population-based cohort of injured workers.

METHODS

All injured workers in the Washington State Workers' Compensation system who received TOS surgery during 1986 to 1991 were identified by computerized bill payment records and validated by medical record review (n = 158). The main outcome measure was work disability status 1 year after surgery. Additional functional status and quality of life outcomes were determined by telephone survey an average of 4.8 years after operation. A sample of workers with a TOS diagnosis who did not receive surgery during 1987 to 1989 were identified as a comparison group (n = 95).

RESULTS

Sixty percent of workers were still work disabled 1 year after surgery. The strongest predictors of remaining disabled were the amount of work disability before surgery (OR = 1.85; 95% CI, 1.51 to 2.28), longer time between injury and TOS diagnosis (OR = 1.34; 95% CI, 1.09 to 1.64), and older age at injury (OR = 1.07; 95% CI, 1.00 to 1.13). There was no relationship between type of surgery, presence of any provocative tests, or experience of surgeon and work disability outcome. In follow-up surveys an average of 4.8 years after surgery, 72.5% of workers still reported they were "limited a lot" in vigorous activities. Compared with a nonsurgical sample of TOS patients, those receiving surgery had 50% greater medical costs and were three to four times more likely to be work disabled.

CONCLUSIONS

The outcome of TOS surgery among injured workers is worse than has generally been reported. The nonspecific neurogenic TOS diagnosis, the complexity of workers' compensation cases, and the adverse event profile are likely substantial contributors to the worse outcomes reported here. Well-designed prospective studies and randomized trials are required to elucidate any role of TOS surgery in nonspecific TOS.