Carpal tunnel syndrome is a condition in which there is excessive pressure on the median nerve. This is the nerve in the wrist that allows feeling and movement to parts of the hand. Carpal tunnel syndrome can lead to numbness, tingling, weakness, or muscle damage in the hand and fingers.
The median nerve provides feeling and movement to the thumb side of the hand. This includes the palm, thumb, index finger, middle finger, and thumb side of the ring finger.
The area in your wrist where the nerve enters the hand is called the carpal tunnel. This tunnel is normally narrow. Any swelling can pinch the nerve and cause pain, numbness, tingling or weakness. This is called carpal tunnel syndrome.
Some people who develop carpal tunnel syndrome were born with a small carpal tunnel.
Carpal tunnel syndrome can also be caused by making the same hand and wrist motion over and over. Using hand tools that vibrate may also lead to carpal tunnel.
Studies have not proved that carpal tunnel is caused by typing on a computer, using a mouse, or repeating movements while working, playing a musical instrument, or playing sports. But, these activities may cause tendinitis or bursitis in the hand, which can narrow the carpel tunnel and lead to symptoms.
Carpal tunnel syndrome occurs most often in people ages 30 to 60. It is more common in women than men.
Other factors that may lead to carpal tunnel syndrome include:
- Alcohol use
- Bone fractures and arthritis of the wrist
- Cyst or tumor that grows in the wrist
- If your body keeps extra fluids during pregnancy or menopause
- Rheumatoid arthritis
Signs & Symptoms
Symptoms may include any of the following:
- Clumsiness of the hand when gripping objects
- Numbness or tingling in the thumb and next two or three fingers of one or both hands
- Numbness or tingling of the palm of the hand
- Pain that extends to the elbow
- Pain in the wrist or hand in one or both hands
- Problems with fine finger movements (coordination) in one or both hands
- Wasting away of the muscle under the thumb (in advanced or long-term cases)
- Weak grip or difficulty carrying bags (a common complaint)
- Weakness in one or both hands
During a physical examination, the following may be found:
- Numbness in the palm, thumb, index finger, middle finger, and thumb side of your ring finger
- Weak hand grip
- Tapping over the median nerve at your wrist may cause pain to shoot from your wrist to your hand (this is called the Tinel sign)
- Bending your wrist forward all the way for 60 seconds will usually result in numbness, tingling, or weakness (this is called the Phalen test)
Tests that may be ordered include:
- Wrist x-rays to rule out other problems, such as arthritis in your wrist
- Electromyography (EMG, a test to check muscles and the nerves that control them)
- Nerve conduction velocity (a test to see how fast electrical signals move through a nerve)
Symptoms often improve without surgery. But more than half of cases eventually need surgery. Even if surgery is successful, full healing can take months.
The following non-surgical treatments may be recommended:
- Wearing a splint at night for several weeks. If this does not help, you may need to wear the splint during the day, as well.
- Avoid sleeping on your wrists.
- Placing warm and cold compresses on the affected area.
Changes you can make in your workplace to reduce the stress on your wrist include:
- Using special devices, such as keyboards, different types of computer mouse, cushioned mouse pads, and keyboard drawers
- Having someone review the position you are in when performing your work activities. For example, make sure the keyboard is low enough so that your wrists are not bent upward while typing. Your provider may suggest an occupational therapist.
- You may also need to make changes in your work duties or home and sports activities. Some of the jobs linked with carpal tunnel syndrome include those that involve vibrating tools.
Furthermore, medication used to treat carpal tunnel syndrome include nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen. Corticosteroid injections given into the carpal tunnel area may relieve symptoms for a period of time.
If none of the non-surgical treatments help, some surgeons will test the electrical activity of the median nerve with an EMG (electromyogram). If the test shows that the problem is carpal tunnel syndrome, carpal tunnel release surgery may be recommended.
Carpal tunnel release is a surgical procedure that cuts into the carpal ligament that is pressing on the nerve. The carpal ligament is a thick ligament (tissue) just under the skin that makes up the top of the carpal tunnel. During the surgery, the surgeon cuts through the carpal ligament to make more space for the nerve and tendons:
- First, the patient receives numbing medication so that no pain is felt during surgery.
- A small surgical cut is made in the palm of the hand near the wrist.
- Next, the ligament that covers the carpal tunnel is cut. This eases the pressure on the median nerve. Sometimes, tissue around the nerve is removed as well.
- The skin and tissue underneath the skin are closed with sutures (stitches).
Sometimes this procedure is done using a tiny camera attached to a monitor. The surgeon inserts the camera into the wrist through a very small surgical cut and views the monitor to see inside your wrist. This is called endoscopic surgery. The instrument used is called an endoscope.
This surgery is done on an outpatient basis – there is no need to stay in the hospital.
After surgery, the wrist will probably be in a splint or heavy bandage for about a week (until the first doctor visit after surgery). After the splint or bandage is removed, motion exercises or a physical therapy program will begin.
Carpal tunnel release decreases pain, nerve tingling, and numbness, and restores muscle strength. Most people are helped by this surgery.
The length of recovery will depend on how long symptoms were present before surgery and how badly damaged the median nerve is. If symptoms were present for a long time, the patient may not be completely free of symptoms after recovery.