Carpal Tunnel Syndrome

Statistics

  • Approximately 260,000 carpal tunnel release operations are performed each year and 47 percent of these are considered to be work-related.
  • A 1999 study reported that 14% of the population surveyed complained of symptoms such as pain, numbness, and tingling in the hands, but only one in five of these people actually had CTS.

What is Carpal Tunnel Syndrome?

There is a nerve called the median nerve that travels from the forearm into your hand through a “tunnel” in your wrist. Wrist bones form the bottom and sides of this tunnel; a ligament covers the top of the tunnel. This tunnel also contains nine tendons that connect muscles to bones and bend your fingers and thumb. These tendons are covered with a lubricating membrane called synovium, which may enlarge and swell under some circumstances. This swelling may cause the median nerve to be pressed up against this strong ligament which may result in numbness, tingling in your hand, clumsiness or pain.

What causes it?

Anything that causes swelling or irritation of the synovial membranes around the tendons in the carpal tunnel can result in pressure on the median nerve.
Some common causes are repetitive and forceful grasping with the hands, repetitive bending of the wrist, broken or dislocated bones in the wrist, obesity, rheumatoid arthritis, thyroid problems, diabetes, hormonal changes of pregnancy and menopause.

What are the symptoms?

Symptoms of carpal tunnel syndrome usually progress gradually over weeks and months and, in some cases, years. The most common symptoms are pain, numbness, and tingling in the wrist, hand, and fingers (except the little finger, which is not affected by the median nerve). There may also be a sense of weakness and a tendency to drop things.

How is it diagnosed?

There are many other conditions that can cause symptoms similar to carpal tunnel syndrome. It is important to be examined by an orthopaedic surgeon or a neurologist, to make sure you do have carpal tunnel syndrome and not something else. A test called a nerve conduction study may be done to evaluate the flow of electricity through the median nerve. Magnetic resonance imaging (MRI) has been found to be accurate in determining the severity of CTS.

There are two very simple tests that most doctors do during the initial exam. About two-thirds of individuals with CTS will have an electrical sensation when the doctor taps over the median nerve at the wrist. Another test that is more specific for CTS is reproduction of the symptoms on flexion of the wrist with the forearm held vertically.

How is it treated?

CTS can range from a minor inconvenience to a disabling condition, depending on its cause and persistence. Many cases of CTS are mild, and some resolve on their own. Treatment will be dependent on the severity of each individual case.

Conservative Therapy:
It is critical to begin treating early phases of CTS before the damage progresses. If possible the person should avoid activities at work or home that may aggravate the condition. Conservative treatment seems to work best in men under 40 and least well in young women.

The affected hand and wrist should be rested for at least two weeks; this allows the swollen, inflamed tissues to shrink and relieves pressure on the median nerve. Ice may provide relief.

Support:
Opinions vary on the use of splints and support as a CTS treatment. Working and resting splints used to be common in early, conservative treatment. Except for anecdotal reports, no evidence exists that these supports actually help. Some experts believe that wrist supports may actually increase the problem by reducing circulation and restricting movement so that the shoulder muscles tense up.

Exercise:
A supervised hand and wrist strengthening exercise program offered by physical or occupational therapists may be beneficial. One study found that most people with CTS felt improvement after two months of physical therapy that included exercises to improve balance and posture.

Medications:
NSAIDS (Nonsteroidal anti-inflammatory drugs) are commonly used to treat CTS. Available over the counter or by prescription, they fight inflammation or swelling and relieve pain.

Cortisone injections into the area may lessen the swelling and ease pressure on the nerve.

Vitamins:
In some studies deficiencies of vitamin B6 have been associated with CTS. One study supported this association and, furthermore, reported that high levels of vitamin B6 were associated with fewer CTS symptoms. Further studies are needed.

Surgery:

In more severe cases surgery to widen the carpal tunnel may be needed. Surgery consists of releasing the ligament that forms the tight roof of the carpal tunnel. This opens and widens the carpal tunnel allowing plenty of room for everything in it and relieving pressure on the nerve.

There are several methods to do this. The standard surgery has involved a 2-3 inch incision. The newer endoscopic procedure uses a small 3/4 inch incision through which tiny instruments are inserted to perform the needed surgery. Other methods are used less often and with decreased success.

What research is being done?

Much of the on-going research on carpal tunnel syndrome is aimed at prevention and rehabilitation. The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) is funding research on carpal tunnel syndrome.

Some of the related information found on Arthritis Insight:

For support visit our Chat Room and Message Boards.
For medication information see our Medication Index.
For more sites about CTS check out our Web Links.
To learn about Carpal Tunnel Surgery visit our Surgery Information.

For more information:

MedicineNet – Carpal Tunnel Syndrome
SCOI – Carpal Tunnel Syndrome
Carpal Tunnel Syndrome: by drdoc online
A Basic Explanation of Carpal Tunnel Syndrome

References:
NIAMS
Well Connected CTS-Copyright © Nidus Information Services 1999
Carpal tunnel syndrome: it’s diagnosis and treatment. Jeffrey S. Malka, M.D., F.A.C.S., F.A.A.O.S.