Carpal Tunnel Syndrome

What is carpal tunnel syndrome?

Carpal tunnel syndrome is numbness, tingling, weakness, pain, and other problems in your hand that are caused by pressure on the median nerve in your wrist. The median nerve and several tendons run from your forearm to your hand. They pass through a small space in your wrist called the carpal tunnel.

The median nerve controls movement and feeling in your thumb and first three fingers. It doesn't control movement of your little finger.


What are the symptoms of carpal tunnel syndrome?

Mild carpal tunnel symptoms most often affect the hand and sometimes the forearm, but they can spread up to the shoulder. Symptoms include:

  • Numbness or pain in your hand, forearm, or wrist that wakes you up at night. (Shaking or moving your fingers may ease this numbness and pain.)
  • Occasional tingling, numbness, "pins-and-needles" sensation, or pain. The feeling is similar to your hand "falling asleep."
  • Numbness or pain that gets worse while you use your hand or wrist. You are most likely to feel it when you grip an object with your hand or bend (flex) your wrist.
  • Occasional aching pain in your forearm between your elbow and wrist.
  • Stiffness in your fingers when you get up in the morning.

With moderate or severe carpal tunnel symptoms, you may have numbness or reduced strength and grip in your fingers, thumb, or hand. It may be hard to:

  • Do simple hand movements, such as brushing your hair or holding a fork. You may accidentally drop objects.
  • Pinch an object between your thumb and first finger. (This is called loss of pinch strength.)
  • Use your thumb while doing simple tasks such as opening a jar or using a screwdriver. With long-term carpal tunnel syndrome, the thumb muscles can get smaller and weaker (atrophy).

Symptoms most often occur in parts of the hand supplied by the median nerve. These are the thumb, the index finger, the middle finger, and half of the ring finger. The median nerve doesn't affect your little finger. So if your little finger is affected, you may not have carpal tunnel syndrome.

Symptoms often occur in both hands, but they are usually worse in one hand than the other. You may first notice symptoms at night. People with carpal tunnel syndrome can usually fall asleep, but pain or numbness may wake them up.

Not all pain in the wrist or hand is caused by carpal tunnel syndrome. There are many other conditions with similar symptoms, such as:

  • An injury to the muscles, ligaments, tendons, or bones.
  • Nerve problems in the fingers, elbow, or neck.
  • Arthritis in the thumb joint or wrist.


Carpal tunnel syndrome

Inflamed median nerve in carpal tunnel syndrome.

The carpal tunnel is a narrow space in the wrist. It contains wrist bones and a ligament (transverse carpal ligament) across the wrist where the palm and forearm meet. Tendons and the median nerve pass through this space to your hand. The median nerve supplies feeling and some movement to part of the hand.

Carpal tunnel syndrome is usually caused when a health condition or problem makes the carpal tunnel space too small. This puts pressure on the median nerve and causes pain, tingling, and other symptoms.

What causes carpal tunnel syndrome?

Carpal tunnel syndrome occurs when a combination of health conditions and activities puts pressure on the median nerve. The median nerve passes through the carpal tunnel in your wrist. This pressure leads to symptoms.

Anything that decreases the amount of space in the carpal tunnel can lead to carpal tunnel syndrome. So can anything that makes the median nerve more sensitive.

Things that help cause carpal tunnel syndrome include:

  • Illnesses such as hypothyroidism, rheumatoid arthritis, and diabetes.
  • Pregnancy.
  • Making the same hand movements over and over. This can cause the tissues within the carpal tunnel to swell. The swelling puts pressure on the median nerve. Some movements can be more likely to cause pressure. These include:
    • Movements in which your wrists are bent.
    • Movements that are done in awkward positions.
    • Forceful hand movements.
    • Hand-arm vibration.

Sometimes the cause of carpal tunnel syndrome can't be found.


Preventing carpal tunnel syndrome

In daily routines at home, at work, or while doing hobbies, think about changing activities in which you make repeated finger, hand, or wrist movements. Train yourself to use other positions or techniques that won't stress your hand or wrist.

  • Take good care of your general health.

    This includes staying at a healthy weight, not smoking, and getting regular exercise.

  • Keep your wrists straight, or only slightly bent, and in line with your arms.

    Avoid activities that bend or twist the wrists for long periods of time. Use hand and wrist movements that spread the pressure and motion evenly throughout your hand and wrist.

  • Take breaks often, and rest your hands.
  • Switch hands and change positions often when you are doing repeated motions.
  • Use your whole hand to grasp an object.

    Avoid gripping with only the thumb and index finger. This can stress your wrist.

  • Stop any activity that you think may be causing finger, hand, or wrist numbness or pain.

    If your symptoms improve when you stop, resume that activity gradually.

  • Wear a wrist splint when you cannot control your wrist motion, such as while sleeping.

    A splint can keep your wrist in a neutral position and reduce the stress on your fingers, hand, or wrist.


How is carpal tunnel syndrome diagnosed?

To diagnose carpal tunnel syndrome, your doctor will ask if you have any health problems, such as arthritis, hypothyroidism, or diabetes. The doctor may ask if you are pregnant. The doctor will ask if you recently hurt your wrist, arm, or neck. Your doctor will want to know about your daily routine and any recent activities that could have hurt your wrist.

During the exam, your doctor will check the feeling, strength, and appearance of your neck, shoulders, arms, wrists, and hands. The doctor may suggest having tests, such as:

  • Nerve testing to check the median nerve.
  • An ultrasound to look at the size of the median nerve.
  • An MRI to find out what is putting pressure on the median nerve.
  • Blood tests to check for a thyroid problem, rheumatoid arthritis, or other conditions.


How is carpal tunnel syndrome treated?

Treatment for carpal tunnel syndrome is based on how serious it is, if there is any nerve damage, and if other treatment has helped.

If your symptoms are mild, home treatment for 1 to 2 weeks is likely to relieve your symptoms. Try these tips.

  • Wear a wrist splint.
  • Stop or change activities that cause numbness and pain.
  • Ice your wrist.
  • Try nonsteroidal anti-inflammatory drugs (NSAIDs) for pain.

Corticosteroids may treat the swelling of the nerve and your pain. They can be taken in pill form or injected into the wrist by a doctor. Physical therapy or occupational therapy is sometimes used.

Surgery is an option. But it's mostly used only when symptoms are so bad that you can't work or do other things even after several weeks to months of other treatment.

The sooner you start treatment, the better your chances are to stop symptoms and prevent long-term damage to the nerve.


How can you care for yourself when you have carpal tunnel syndrome?

  • If possible, stop or reduce the activity that causes your symptoms. If you cannot stop the activity, take frequent breaks to rest and stretch or change hand positions to do a task. Try switching hands, such as when using a computer mouse.
  • Try to avoid bending or twisting your wrists.
  • Ask your doctor if you can take an over-the-counter pain medicine, such as acetaminophen (Tylenol), ibuprofen (Advil, Motrin), or naproxen (Aleve). Be safe with medicines. Read and follow all instructions on the label.
  • If your doctor prescribes corticosteroid medicine to help reduce pain and swelling, take it exactly as prescribed. Call your doctor if you think you are having a problem with your medicine.
  • Put ice or a cold pack on your wrist for 10 to 20 minutes at a time to ease pain. Put a thin cloth between the ice and your skin.
  • If your doctor or your physical or occupational therapist tells you to wear a wrist splint, wear it as directed to keep your wrist in a neutral position. This also eases pressure on your median nerve.
  • Ask your doctor whether you should have physical or occupational therapy to learn how to do tasks differently.
  • Try a yoga class to stretch your muscles and build strength in your hands and wrists. Yoga has been shown to ease carpal tunnel symptoms.

To prevent carpal tunnel

  • When working at a computer, keep your hands and wrists in line with your forearms. Hold your elbows close to your sides. Take a break every 10 to 15 minutes.
  • Try these exercises:
    • Warm up: Rotate your wrist up, down, and from side to side. Repeat this 4 times. Stretch your fingers far apart, relax them, then stretch them again. Repeat 4 times. Stretch your thumb by pulling it back gently, holding it, and then releasing it. Repeat 4 times.
    • Prayer stretch: Start with your palms together in front of your chest just below your chin. Slowly lower your hands toward your waistline while keeping your hands close to your stomach and your palms together until you feel a mild to moderate stretch under your forearms. Hold for 10 to 20 seconds. Repeat 4 times.
    • Wrist flexor stretch: Hold your arm in front of you with your palm up. Bend your wrist, pointing your hand toward the floor. With your other hand, gently bend your wrist further until you feel a mild to moderate stretch in your forearm. Hold for 10 to 20 seconds. Repeat 4 times.
    • Wrist extensor stretch: Repeat the steps for the wrist flexor stretch, but begin with your extended hand palm down.
  • Squeeze a rubber exercise ball several times a day to keep your hands and fingers strong.
  • Avoid holding objects (such as a book) in one position for a long time. When possible, use your whole hand to grasp an object. Using just the thumb and index finger can put stress on the wrist.
  • Do not smoke. It can make this condition worse by reducing blood flow to the median nerve. If you need help quitting, talk to your doctor about stop-smoking programs and medicines. These can increase your chances of quitting for good.

Copyrighted material adapted with permission from Healthwise, Incorporated. This information does not replace the advice of a doctor.