The median nerve gives feeling and movement to the palm side of your hand. This includes the palm side of the thumb, index, finger, middle finger, and ring finger.
The area in your wrist where this 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 pain and swelling of the tendons or bursa.
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:
- 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
Exams and Tests
During a physical exam, your health care provider may find:
- 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:
Your health care provider may suggest the following:
- 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 health care 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.
Medications used in the treatment of 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.
Carpal tunnel release is a surgical procedure that cuts into the ligament that is pressing on the nerve. Surgery is successful most of the time, but it depends on how long the nerve compression has been occurring and how severe it is.
Symptoms often improve without surgery. But more than half of cases eventually need surgery. Even if surgery is successful, full healing can take months.
If carpal tunnel is not treated, the nerve can be damaged. This damage can cause permanent weakness, numbness, and tingling.
When to Contact a Medical Professional
Call for an appointment with your health care provider if:
- You have symptoms of carpal tunnel syndrome
- Your symptoms do not respond to regular treatment, such as rest and anti-inflammatory medications, or if there seems to be a loss of muscle bulk around your fingers
Use tools and equipment that are properly designed to reduce the risk of wrist injury.
Ergonomic aids, such as split keyboards, keyboard trays, typing pads, and wrist braces, may be used to improve wrist posture during typing. Take frequent breaks when typing and always stop if you feel tingling or pain.
Median nerve dysfunction; Median nerve entrapment
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Tosti R, Asif IM. Acute carpal tunnel syndrome.Orthop Clin N Am
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Update Date 5/15/2014
Updated by: C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.