Long-term loss of wages seen after wrist disorder

NEW YORK (Reuters Health) - Carpal tunnel syndrome can keep people out of work for months, and even lower their earnings for years to come, according to a study by the Washington State labor department.

In an analysis of nearly 8,800 workers' compensation claims made in the state between 1993 and 1994, researchers found that workers with the wrist disorder lost more days of work and experienced a steeper drop in their long-term wages than those who'd filed due to an arm fracture.

Six years after filing for their injuries, workers with carpal tunnel syndrome were making less than half their pre-injury wages, on average.

Michael Foley and colleagues at the Washington State Department of Labor and Industries in Olympia report the findings in the American Journal of Industrial Medicine.

Carpal tunnel syndrome is a disorder affecting the wrist and hand caused by pressure on the median nerve, which runs from the forearm into the hand through a narrow passageway in the wrist -- the carpal tunnel. Symptoms include pain, numbness and weakness in the hand, fingers and wrist, and left untreated, the condition can cause long-term damage to nerves and muscles.

Research has shown that some people seem to have a genetic predisposition to carpal tunnel syndrome, and that certain conditions -- such as diabetes, arthritis, obesity and even pregnancy -- can contribute to the wrist disorder.

While popular wisdom holds that repetitive motions like typing cause carpal tunnel syndrome, studies have refuted this -- although certain jobs, such as working with vibrating tools, may at least worsen symptoms.

Whatever the cause, the new findings suggest that the pain of this condition can keep people off the job for a long period and then sharply lower their earnings for years afterward.

Workers in certain industries, such as men in construction, have a particularly tough time returning to their old line of work at all, Foley told Reuters Health.

He and his colleagues based their findings on quarterly earnings records for 8,760 Washington State workers who filed claims for one of three conditions: carpal tunnel syndrome, an arm fracture or dermatitis (skin inflammation).

Compared with workers who'd suffered an arm fracture, those with carpal tunnel syndrome were out on workers' compensation three times longer -- for a median of 138 days, versus 46 days. And although workers with fractures recovered most of their pre-injury earnings and those with dermatitis recovered 100 percent, workers with carpal tunnel syndrome recovered only 45 percent.

Over the 6-year study, each carpal tunnel syndrome claimant lost $45,000 to $89,000, the researchers estimate.

It's not clear why workers with this syndrome fared worse than those with fractures, but Foley pointed out that carpal tunnel syndrome is fundamentally different from a bone break, which is sudden and hard to ignore. It is a chronic condition that workers may not at first recognize as a problem or choose to dismiss it until the symptoms become severe.

Foley said the findings highlight the importance of early diagnosis and treatment of carpal tunnel syndrome; indeed, workers who were diagnosed more promptly and had surgery -- a treatment option for carpal tunnel syndrome -- recovered much more of their earnings by the 6-year mark.

It's also important for employers to try to accommodate workers when they first return to work, Foley said. This includes, whenever possible, giving them tasks that are less likely to aggravate their symptoms as they are recovering.

SOURCE: American Journal of Industrial Medicine, March 2007.