Carpal tunnel syndrome (CTS) occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes pressed or squeezed at the wrist.
The carpal tunnel is a narrow, rigid passageway of ligament and bones at the base of the hand that houses the median nerve and the tendons that bend the fingers. The median nerve provides feeling to the palm side of the thumb and to most of the fingers.
Symptoms usually start gradually, with numbness, tingling, hand weakness, and sometimes pain in the hand and wrist. CTS makes it difficult for some people to drive, read a book, grasp small objects, or do other tasks.
Sometimes no direct cause of CTS can be found; contributing factors include trauma or injury to the wrist that causes swelling, as well as thyroid disease, rheumatoid arthritis, and fluid retention during pregnancy. Women are three times more likely than men to develop carpal tunnel syndrome. The disorder usually occurs only in adults.
Initial treatment generally involves wearing a splint at night to keep the wrist from bending, over-the-counter and prescription drugs including non-steroidal anti-inflammatory drugs to temporarily reduce swelling and ease pain, and injections of corticosteroid drugs (such as prednisone). For more severe cases, surgery may be recommended.
Underlying causes such as diabetes or arthritis should be treated first. Alternative therapies such as yoga can reduce pain and improve grip strength in some people with CTS.
In general, carpal tunnel syndrome responds well to treatment, but less than half of individuals report their hand(s) feeling completely normal following surgery. Some residual numbness or weakness is common. Most people may need to modify work activity for several weeks following surgery.
Stretching exercises, taking frequent rest breaks, wearing splints to keep wrists straight, and using correct posture and wrist position can help prevent or worsen symptoms. Making changes in the workplace may help but may not prevent the occurrence of carpal tunnel syndrome.
NINDS-funded scientists are studying the factors that lead to long-lasting nerve pain disorders, and how the affected nerves are related to symptoms of numbness, loss of function, and pain.
Researchers also are examining biomechanical stresses that contribute to the nerve damage responsible for symptoms of carpal tunnel syndrome in order to better understand, treat, and prevent it.
Other NIH research will evaluate the effects of acupuncture and other therapies in tailoring individual treatment programs, as well as research on tissue damage associated with repetitive motion disorders, including carpal tunnel syndrome.