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January 19, 2006

Carpal Tunnel Syndrome: Who Should Pay?

Back in December fellow Insider blogger Julie Ferguson wrote about a Harvard Medical School newsletter that finds no relationship between keyboarding and carpal tunnel syndrome. This information has been out there for a while, based upon a 2003 study of 5,600 Danish workers. But for those of us who track workers compensation, these findings raise significant issues. If carpal tunnel is usually not work related, why are workers comp carriers routinely paying for all those surgeries?

What is Carpal Tunnel
According to The Harvard newsletter, carpal tunnel syndrome occurs when the median nerve (one of the three main nerves that pass through the wrist to the fingers) is compressed or pinched. This usually occurs as the nerve passes through a tunnel of tough fibers that runs between small bones in the wrist - the carpal tunnel.

Carpal tunnel syndrome is a relatively new phenomenon. You may remember the informational videos that came out in the early 1990s, which dramatically presented the classic symptoms of carpal tunnel: pain, weakness and tingling in the thumb, index finger, middle finger and half of the ring finger. Many people viewed the videos and immediately started feeling the symptoms! In any event, only 2 percent to 3 percent of the general population has carpal tunnel syndrome.

As anyone working in the comp system knows, women are twice as likely to develop carpal tunnel syndrome as men - and the risks increase with age. It's thought to arise from a combination of factors that increase pressure on the median nerve and surrounding tendons. The contributing factors are not work related: having a small carpal tunnel to begin with; having a history of certain diseases such as diabetes or rheumatoid arthritis; or having a previous bone dislocation or fracture. Being overweight or obese increases the risk; so does pregnancy. Keeping your wrists bent while sleeping, reading or driving also appears to increase the risk.

The newsletter points out that certain jobs involving assembly-line work - for instance, manufacturing, sewing, cleaning and meat-packing - can also make people more prone to carpal tunnel syndrome. (In other words, for workers performing these jobs, carpal tunnel may well be work related and compensable.) But using a computer does not appear to increase the risk for carpal tunnel syndrome. The Danish study, published in the Journal of the American Medical Association in 2003, found that workplace computer use does not pose a risk of developing carpal tunnel syndrome. And a 2001 study in Neurology of computer users at a medical facility found that heavy computer use (up to seven hours a day) did not increase a person's risk of developing carpal tunnel syndrome.

Carpal Tunnel vs. Repetitive Stress
So here is the crux of the matter: a typist who develops carpal tunnel syndrome probably does not have a work-related condition. But a typist who develops repetitive stress problems does. Repetitive stress involves the neck, shoulders, arms and hands and includes hand and wrist pain caused by repetitive finger motions and contracting the forearm and wrist muscles for long periods of time. Contributing factors in repetitive stress injuries include incorrect positioning of the keyboard and computer mouse, remaining in a seated posture, and gripping a computer mouse for long time periods - all of which can certainly be work-related. However, no matter how long you type, or what position you type in, you will not develop carpal tunnel syndrome, unless you have a prediliction for it.

As a result, if the diagnosis for an office worker is carpal tunnel syndrome, the comp carrier could actually deny the claim. On the other hand, if the diagnosis is repetitive stress syndrome, it's probably work related. So why is this such a big deal?

Carpal Tunnel in the Comp System
In a major study published by NCCI (PDF) in April of 2005, we learn that carpal tunnel in the comp system ranks second among major lost time diagnoses - second only to lower back strain. Sixty per cent of carpal tunnel claims lead to lost time - compared to only 34 per cent for lower back strains. The older people get, the more likely that their carpal tunnel will be treated with surgery - and where surgery is the treatment, the costs are three times higher. It's interesting to note that the average cost per carpal tunnel claim without attorney involvement is $16,000. When an attorney is involved, the average cost jumps to $29,000. That's a high average cost by any measure. Overall, carpal tunnel is nearly a billion dollar line item in the comp system.

We have seen that carpal tunnel claims among industrial workers truly belong in the comp system, because work is a contributing factor. But when NCCI examined the occupational classes involved in workers comp carpal tunnel claims, they found that among both male and female workers, the number one occupation is office and clerical. In other words, the comp system is routinely accepting the claims that are least likely to be work related!

Who Pays?
Thus we find that the workers comp system is paying for what appears to be a non-work-related condition. Insurers front the substantial costs of treatment and the employer subsequently gets hammered through the experience rating process, paying higher premiums for three full years. We are not aware of any insurers attempting to deny coverage based upon the emerging literature on the causes of carpal tunnel. (If any such carriers are reading this blog, please respond! We will keep your identity anonymous, if you wish.)

Who should pay?
When office workers develop carpal tunnel, it should probably be covered by conventional health insurance, not workers comp. But don't look for a paradigm shift any time soon. Insurers, always slow to change, are probably waiting for more information. Their lawyers would like to see a bullet proof study. It will take more than a few thousand Danes to sway administrative law judges in comp courts around the country. Nevertheless, this will prove to be yet another fascinating component in the health care debate. Carpal tunnel might not be work related, but it is likely to remain compensable in the workers comp system for the foreseeable future.

Posted by Jon Coppelman at 1:22 PM Link to, Comment (3), or E-mail this post

Work related or not ... that it the question.
(kudos to Bill Shakespeare) It seems the real question is how do you define a work injury. In Pennsylvania, a work injury includes any activation, aggravation or aceleration of a condition. Under that definition, you could have a work injury if your physical predisposition, ie, your small "tunnels" resulted in symptoms from your overuse, ie swelling, irritation, etc.
Even from my defense-oriented point of view, I believe you have a work injury when the work activities cause or increase symptoms, to the point of disability. However, I would distinguish tired or sore muscles, at the end of a busy work day, form a "work injury" definition. But what if every day is too much? I believe some people are not Physicaly (or mentally) "cut out" for some jobs. Does that mean the overweight female with small carpal tunnels is disabled by CTS, but another individual, with those nice size carpal tunnels is not ?
I don't know, for me, it comes back to a question of definition. Yes, some people are disabled by activities that would not disable everyone. I think you take your employees as you find them.

Posted by: Michael D. Sherman at January 20, 2006 5:02 PM

In order to deny a claim as described in the article, from a workflow viewpoint, the carriers need to have a medical opinion from another Dr. stating that the work injury is not related to work. The study itself would not do it. In Pa the treating physician has to state with "reasonable medical certainty" that the CTS is due to work. The carrier would have to find another Dr. to contest, and with most jurisdictions, th etreating Dr. is given more credibility.
This is a paradigm shift that will take a long time.

Posted by: Dave at January 23, 2006 9:14 AM

I have to disagree with you, principally about the Danish study, which is apparently a significant source for your conclusion that CTS is not related to computer use.

The Danish study found that computer use as a general matter was not correlated with CTS. It found average mouse use of somewhere around 10 hours per week and that this level of mouse usage was not correlated with an increased risk of CTS.

However, it found an increased risk of CTS among those who used the mouse more than 20 hours per week. So the conclusion that CTS and computer use are not correlated is not warranted by the study. The fact is that you have to dig deeper and determine what sort of physical activities are involved. Because of the peculiar positioning and straining involved in using the mouse more than half the work-week, that activity can be correlated with CTS.

I have seen many doctors who just tell my clients that they have CTS because they work on a computer. Now, that's just not true. But I've also had insurance carrier doctors who insist that CTS can't be caused by any activities, for it only occurs spontaneously without cause, and that conclusion is equally without warrrant.

Posted by: Alan at January 26, 2006 6:01 PM
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