Patient information from BMJ

Carpal tunnel syndrome

Last published:Jan 05, 2023

If you have carpal tunnel syndrome, you may get numbness or tingling in your thumb and fingers. You may also have aching in your wrist. Treatment can often relieve the symptoms and help prevent long-term damage.

You can use our information to talk to your doctor and decide which treatments are best for you.

What is carpal tunnel syndrome?

Your carpal tunnel is a narrow gap between the bones inside your wrist. The nerve that carries messages between your brain and your hand runs through this gap. If you have carpal tunnel syndrome, the gap gets narrower and squeezes this nerve.

Although some illnesses, such as rheumatoid arthritis, can cause carpal tunnel syndrome, it's often not possible to say why someone gets carpal tunnel syndrome. But we do know that certain things can make it more likely. These include:

• being a woman

• being over 30 years old

• being overweight

• having a job that involves a lot of bending or twisting of the hands or wrists, and

• working with vibrating tools.

Women sometimes get carpal tunnel syndrome while pregnant, but it usually goes away after they give birth.

What are the symptoms?

Symptoms of carpal tunnel syndrome can include:

• numbness, tingling, burning, or aching pains in your wrist, hand, and fingers

• a weak grip, which might cause you to drop things

• pain that gets worse when you make repetitive movements, or when you hold your hand in one position: for example, when holding a book or phone, and

• numbness and pain that wake you up at night.

Carpal tunnel syndrome can affect both your hands. If it does, the hand you use most (your right hand if you're right-handed) will probably be worse.

To diagnose carpal tunnel syndrome, your doctor will ask you about your symptoms and examine your wrist and hand.

You may also have a test that measures the electrical activity of your nerves and muscles to confirm that you have carpal tunnel syndrome (and not another condition) and to see how bad it is. You may hear this test called an electromyogram.

What treatments are available?

Carpal tunnel syndrome that's left untreated can sometimes cause permanent damage. So it's important to get treatment as early as possible. 

Two of the main treatments for carpal tunnel syndrome are wrist splints and injections of corticosteroids.

If splints and corticosteroid injections don't help - or if your carpal tunnel syndrome is severe - your doctor may recommend surgery.

Some treatments for carpal tunnel syndrome, such as medicines, aren't usually given to women who are pregnant. But splints can be helpful.

Splints

Your doctor may suggest wearing a splint at night to stop your wrist bending. Your doctor will probably recommend wearing a splint at night for at least one month, and for longer if it helps. 

Research suggests that about 70 in 100 people find splints helpful.

Wearing a splint during the day as well doesn't seem to help any more than just wearing it at night. However, your doctor may recommend limiting any activities during the day that make your symptoms worse.

You can buy ready-made wrist splints, or you can have one custom made to fit your wrist. You can discuss your options with your doctor.

Corticosteroid injections

If splints alone aren't helping enough, your doctor may recommend also having an injection of a medicine called a corticosteroid into your wrist. These drugs are powerful anti-inflammatories that can help reduce any swelling that is putting pressure on the nerves in your wrist.

Research suggests that between 60 and 70 in 100 people who have these injections find them helpful within a few weeks. These improvements can last for several months. 

These injections can sometimes damage the tendons or nerves in the wrist. Your doctor should discuss the possible risks with you before you have this treatment.

Surgery

Surgery can take the pressure off the nerve in your wrist if you have more severe carpal tunnel syndrome or if other treatments haven't worked. 

This surgery doesn't seem to help everyone. But between 80 and 90 in 100 people who have this surgery find that it helps.

You will be awake during the surgery but you will be given a local anaesthetic to make your wrist numb.

Doctors can do the operation through a cut at the base of your hand, which will be about 5 centimetres (2 inches) long. Or they can use keyhole surgery, which is done through smaller cuts with the help of a tiny camera.

Both operations work about as well as each other, but having keyhole surgery may mean you'll recover a bit faster.

You should be able to go home the same day as your operation. Like any operation, this surgery can have side effects in some people. These side effects are usually mild and temporary. They can include:

• nerve damage

• numbness

• weakness in your hand, and

• pain in the scar.

What to expect in the future

Many people with carpal tunnel syndrome find that their symptoms get slowly worse. But this can take several years. Carpal tunnel syndrome can also get better for periods of time, especially after pregnancy.

But don't ignore your symptoms. After a while, if the nerve becomes more damaged it may actually be harder to notice that something is wrong. If you have any numbness, tingling, pain, or weakness in your hand or wrist, see your doctor. Most people will get better with treatment.