Carpal Tunnel Syndrome

Carpal tunnel syndrome results from compression (pinching) of the median nerve. The compression can be caused by swelling of tissue around or in the tunnel or by bands of fibrous tissue that form on the palm side of the wrist.

Pregnant women and people who have diabetes Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Urination and thirst are... read more , an underactive thyroid gland Hypothyroidism Hypothyroidism is underactivity of the thyroid gland that leads to inadequate production of thyroid hormones and a slowing of vital body functions. Facial expressions become dull, the voice... read more , certain forms of amyloidosis Amyloidosis Amyloidosis is a rare disease in which abnormally folded proteins form amyloid fibrils that accumulate in various tissues and organs, sometimes leading to organ dysfunction, organ failure, and... read more , or rheumatoid arthritis Rheumatoid Arthritis (RA) Rheumatoid arthritis is an inflammatory arthritis in which joints, usually including those of the hands and feet, are inflamed, resulting in swelling, pain, and often destruction of joints.... read more are at increased risk of developing carpal tunnel syndrome. Also at risk are people whose work requires repeated forceful movements with the wrist extended, such as using a screwdriver. Another potential (but controversial) factor is use of a computer keyboard that is not positioned properly. Prolonged exposure to vibrations (for example, by using certain power tools) has also been claimed to cause carpal tunnel syndrome. However, most cases develop for unknown reasons.

The symptoms of carpal tunnel syndrome are odd sensations, numbness, tingling, and pain in the first three fingers and half of the fourth finger on the thumb side of the hand. Sometimes the entire hand may be affected. Occasionally, there is also pain and a burning or tingling sensation in the forearm.

Burning or aching pain with numbness and tingling often wake people at night because of the way the hand is positioned. The person may shake the hand to try to restore normal feeling.

With time, the muscles in the hand on the thumb side can weaken and shrink through lack of use (atrophy).

The diagnosis of carpal tunnel syndrome is made largely by examining the affected hand and wrist. A doctor may do nerve conduction studies Nerve conduction studies Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Electroencephalography (EEG) is a simple, painless procedure in which... read more or advanced imaging tests, such as magnetic resonance imaging Computed tomography (CT) and magnetic resonance imaging (MRI) A doctor can often diagnose a musculoskeletal disorder based on the history and the results of a physical examination. Laboratory tests, imaging tests, or other diagnostic procedures are sometimes... read more (MRI) or ultrasound, to be certain that the problem is carpal tunnel syndrome, particularly if surgery is being considered.

Avoiding positions that overextend the wrist or put extra pressure on the median nerve and adjusting the angle of a computer keyboard sometimes provide some relief. Wearing wrist splints that hold the hand in a neutral position (especially at night) and taking mild pain relievers often help.

Treating underlying disorders (such as rheumatoid arthritis Rheumatoid Arthritis (RA) Rheumatoid arthritis is an inflammatory arthritis in which joints, usually including those of the hands and feet, are inflamed, resulting in swelling, pain, and often destruction of joints.... read more or an underactive thyroid gland Hypothyroidism Hypothyroidism is underactivity of the thyroid gland that leads to inadequate production of thyroid hormones and a slowing of vital body functions. Facial expressions become dull, the voice... read more ) can help relieve symptoms.

Injections of a corticosteroid Corticosteroids Rheumatoid arthritis is an inflammatory arthritis in which joints, usually including those of the hands and feet, are inflamed, resulting in swelling, pain, and often destruction of joints.... read more into the carpal tunnel occasionally bring long-lasting relief.

If pain or numbness is severe or if the muscle atrophies or weakens, surgery is the best way to relieve pressure on the median nerve. A surgeon can cut away the bands of fibrous tissue that place pressure on the nerve.