Computer Use Deleted As Carpal Tunnel Syndrome Cause: More Common In Assembly Line Work

The pain, numbness, and tingling are more common in those who do assembly-line work in industries such as manufacturing, sewing, cleaning, or meatpacking. Genes account for about half the cases. Women are more likely than men to suffer the syndrome.

Additional factors involve weight, pregnancy, and some diseases. Being overweight doubles the risk, according to several medical studies.

Between 20 and 60 percent of pregnant women develop the disorder, but symptoms usually go away after the baby is delivered. Diseases such as diabetes, rheumatoid arthritis, and lupus, and thyroid problems, connective tissue disorders, as well as previous bone dislocation or fracture, are also linked to a higher risk of developing carpal tunnel syndrome.

It's estimated to affect between 2 and 3 percent of adults, or millions of people in the United States alone. Often the disorder is classified as a repetitive stress injury, but a Harvard health publication says that's incorrect.

Surgery to relieve the pressure causing this nerve disorder is one of the most common procedures in the United States, with more than 200,000 carpal tunnel surgeries performed every year. However, many people improve with splints or steroid injections.

Ordinary pain drugs, such as aspirin, ibuprofen, and naproxen, don't help. Neither do super pain medications like Celebrex or Vioxx. There's no scientific evidence that vitamin B6 helps, although some books recommend taking it.

According to one study, twice-weekly yoga sessions for two months reduced pain and provided better grip strength than using splints or doing nothing at all. The National Institutes of Health says that acupuncture may be helpful, especially in addition to other treatments. The Harvard report notes that some people prefer to try acupuncture before choosing surgery.

What's in the tunnel

The carpal tunnel is formed from a U-shaped cluster of eight bones at the base of your palm. A strong ligament arches across these bones, providing a roof for the tunnel. Within it lies the so-called median nerve, which travels all the way from the spinal cord and controls sensations to the palm side of the thumb and the fingers. This nerve also transmits impulses to hand muscles that move the fingers and thumb. When the tunnel narrows, it can create pressure that decreases blood supply to the nerve. This decreased blood supply results in the pain, weakness, and tingling that announce the syndrome.

These symptoms often occur at night, adding sleeplessness to the pain. Sleeping with your wrists bent, a common habit, can add to the misery. After awakening, you may need to shake your hand to restore normal feeling.

As things get worse, you may feel tingling during the day, and pain radiating up your arm. It may become difficult to make a tight fist, grasp small objects, or do things with your hands that you could do before. In the severest cases, muscles at the thumb base weaken. You could even lose the ability to distinguish between hot and cold by touch.

What to do

Such symptoms should drive you to the doctor. He or she will examine you to find out if your complaints might be due to other conditions. Then there will be tests for signs of tenderness and swelling in wrists, hands, and fingers.

In one test, the doctor taps or presses on the median nerve. If that produces tingling in the fingers, or a shocklike sensation, you probably have carpal tunnel syndrome. Or a decision may be made by a wrist-flexing exercise. If your fingers tingle or feel numb after one minute of holding your elbows straight and flexing your hands and wrists, you need help.

Wearing a splint that prevents your wrist from moving up or down will help. Many people wear the splint during the night to prevent aggravating the condition.

Steroid injections into the carpal tunnel may provide relief, especially in younger patients who have had the symptoms for a short while. In one study, 70 percent of people reported satisfaction with the treatment after two weeks. Longer-term results are mixed, with some studies finding that pain returns within two to four months for most people. Research completed in 2005 concluded that steroid injection eased symptoms more effectively than surgery in the first three months after treatment. However, the two turned out to be equally effective a year after treatment.

Less than a third of people end up needing surgery, but lots of patients have it. The surgery creates more space in the tunnel by loosening the rooflike ligament, thus relieving pressure on the median nerve. Most of the time, the procedure is done using local anesthesia, and it doesn't require an overnight stay in the hospital.

Success rates run high. Eighty to 90 percent of people report relief of daytime and nighttime symptoms after six months. But it may take a year or more before they regain their strength and feel back to normal.

For more information, inquire about the publication "Hands: Strategies for Strong, Pain-Free Hands" at http://www.health.harvard.edu/HND.