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Carpal Tunnel Syndrome


The Manual's Editorial Staff

Last full review/revision Oct 2019| Content last modified Oct 2019
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What is carpal tunnel syndrome?

Carpal tunnel syndrome is pain, numbness, and tingling in your fingers and hand. Those feelings are caused by pressure on a nerve in your wrist.

  • The carpal tunnel is a space (channel) on the palm side of your wrist

  • The median nerve runs through the carpal tunnel

  • Pressure on the nerve can cause carpal tunnel syndrome

  • Treatment usually involves pain relievers taken by mouth, a splint, a shot of medicine called a corticosteroid, and sometimes surgery

What causes carpal tunnel syndrome?

Carpal tunnel syndrome happens when the median nerve in your wrist is squeezed from swelling or bands of hard tissue within the carpal tunnel. Usually the cause is unknown. But some repetitive actions may lead to carpal tunnel syndrome, including:

  • Work that requires you to bend up your wrist too far in a repeated, forceful way, such as using a hammer

  • Using a keyboard in an incorrect position

  • Using objects that vibrate for a long time (for example, certain power tools)

You're more likely to get carpal tunnel syndrome if you have certain medical conditions, such as diabetes or rheumatoid arthritis.

What are the symptoms of carpal tunnel syndrome?

Symptoms may happen in one or both hands:

  • Numbness, burning, tingling, and pain in your thumb, index, middle, and part of your ring fingers

  • Burning or aching pain with numbness and tingling that often wakes you up at night

  • Weakness and difficulty holding things in your hand

  • Over time, the thumb muscles can weaken and shrink

How can doctors tell if I have carpal tunnel syndrome?

  • The doctor will review your symptoms and examine your hand and wrist

  • The doctor may do a test that sends small electric shocks through your wrist to measure how fast and strong the nerve sends signals through the nerve (nerve conduction test)

How do doctors treat carpal tunnel syndrome?

Treatment can include:

  • Avoiding positions that bend your wrist too much or put pressure on your wrist, like using a keyboard incorrectly

  • Wearing wrist splints to keep your wrists straight, especially while sleeping or when using a keyboard or hand tool

  • Taking mild pain relievers such as ibuprofen or acetaminophen

  • Getting shots into your wrist (carpal tunnel) of medicine called corticosteroids, if the pain is severe

  • Having surgery, if your pain is severe or your muscle shrinks or weakens

How can I prevent carpal tunnel syndrome?

You should avoid positions that bend your wrist too much or put extra pressure on the nerve.

Use a keyboard in the correct position:

  • Keep your hand, wrist, and forearm in a straight line

  • Use a wrist pad to support your wrist, if needed

Proper Keyboard Position

Using a computer keyboard that is positioned improperly may cause or contribute to carpal tunnel syndrome. To prevent injury, the user should keep the wrist in a neutral position. That is, the line from the hand to the forearm should be straight. The hand may be slightly lower than the forearm. But the hand should never be higher, and the wrist should not be cocked. The keyboard should be positioned relatively low, keeping the hand slightly lower than the elbow. A wrist pad can be used to support the wrist.

Proper Keyboard Position
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