What Is Carpal Tunnel Syndrome?
The carpal tunnel is a narrow passage in the wrist that protects the main nerve of the hand and the tendons that move and flex the first three fingers. Carpal tunnel syndrome is caused by compression of a nerve in the wrist. When compressed, the nerve produces feelings of tingling, numbness, and weakness. Treatment may include conservative approaches like ice and splints, cortisone injections, and surgery for severe symptoms.
The Carpal Tunnel
The carpal tunnel is formed by the wrist bones on the bottom and sides of the hand, while and its “top” is covered by the transverse ligament, which is a strong band of connective tissue known as the flexor retinaculum. Inside the tunnel are the median nerve and nine tendons, which extend from the arm muscles that are used to move your index finger, middle finger, and thumb.
A lubricating membrane, the synovium, covers the tendons and may swell under certain conditions. If the swelling presses the nerve against the transverse ligament, you will feel the effects of numbness and tingling.
Carpal Tunnel Syndrome Symptoms
Carpal tunnel syndrome tends to start with symptoms of numbness and tingling in your middle, thumb, or index finger that come and go, often at night.1 As the syndrome progresses, you may feel the sensations during the day when you are using your hand. Shaking out your hand gets rid of the numbness or discomfort.
Over time, the numbness can become constant. You can also experience weakness in the hands, clumsiness, decreased grip strength, and difficulty in doing tasks for which you need manual dexterity. If carpal tunnel syndrome is left untreated, it can lead to muscle damage.
Carpal Tunnel Symptoms
There are many causes and risk factors that increase the chances of getting carpal tunnel syndrome. A wrist dislocation or fracture may create a change in pressure in the carpal tunnel, increasing the chances for median nerve damage. Women are more likely to have this condition because of their smaller carpal tunnel. Obesity is also a common risk factor.
Fluid retention, specifically during pregnancy or menopause, can increase pressure on the median nerve as well.1
Certain medical conditions, such as diabetes, rheumatoid arthritis, osteoarthritis, kidney failure, or thyroid disorders, are associated with an increased risk for carpal tunnel syndrome.
Working with vibrating tools or moving the wrist repetitively for long periods of time are additional factors that can increase the chances of developing this disease. The risk is greater in assembly line work in manufacturing and food processing, while risk from computer use is less supported by research.2
Carpal Tunnel Causes and Risk Factors
In order to diagnose carpal tunnel syndrome, your doctor will start with a physical examination and run a few different tests. These can include an X-ray to rule out any other cause of wrist pain, such as a fracture or arthritis; an electromyogram that evaluates the electrical activity in the muscles of the arm and hand; and a nerve conduction study, which measures how well the nerves are conducting signals.1
How Carpal Tunnel Syndrome Is Diagnosed
There are many ways to treat carpal tunnel syndrome, depending on the severity of the condition. Those who have mild symptoms can treat their wrist discomfort and pain by frequently resting their arms, avoiding any strenuous physical activity and movements of the arms, and applying ice packs if there is swelling.
If these do not provide relief within several weeks, your doctor can provide other options. Wrist splinting can relieve pressure on the nerve and reduce tingling and numbness, especially at night.1 Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, help to reduce swelling while providing temporary pain relief. Corticosteroid injections can decrease the swelling and inflammation of the median nerve and have been found to be effective.
Surgery is an option if the carpal tunnel symptoms are severe and extremely painful, and if there is no progress after nonsurgical treatment. Carpal tunnel surgery relieves the pressure on the median nerve by releasing the ligament producing the pressure that is irritating the nerve. This can be done by either endoscopic surgery or open surgery.1
Treating Carpal Tunnel Syndrome
You can help reduce your risk of carpal tunnel syndrome by maintaining a healthy body weight and managing conditions such as diabetes and rheumatoid arthritis that contribute to this condition. You can also do wrist-stretching exercises.3
Avoid sleeping on your wrists and maintain good posture, positioning, and grip in everyday tasks to reduce wrist strain. If you perform repetitive tasks at work or at home, take frequent breaks and change your hand and body position often. If you work at a computer, ensure you are using good posture and your wrists are not in a flexed position when you type.
How to Prevent Carpal Tunnel Syndrome
Coping with carpal tunnel syndrome can be frustrating. You use your hands in many ways, and it inhibits life’s tasks and pleasures to have numbness and weakness. However, it’s never too late to discuss your symptoms with your doctor. Most people can get effective treatment.