What is carpal tunnel syndrome?

Carpal tunnel syndrome happens when the median nerve comes under pressure in your wrist. The median nerve:

• carries the sense of touch to your thumb and most of the next 2 fingers
• controls movement for some of your hand muscles

The median nerve travels down your arm and through the carpal tunnel in your wrist. This is a narrow passageway with just enough room for your tendons and nerves to pass through.

When your tendons swell or thicken, they take up more space in the carpal tunnel. This leaves less space for the median nerve, and it can become compressed.

What are the symptoms related to carpal tunnel syndrome?

The most common symptoms of carpal tunnel syndrome are:

• tingling or numbness in your fingers or hand
• nerve pain in your wrist or hand, which can spread up your arm or down to your fingers
• weakness in your hands, making it hard to grip things
• your fingers may feel swollen

Tingling in your hands and fingers can feel like pins and needles. It usually occurs in the:

• palm of your hand
• thumb
• the 2 fingers next to your thumb (the pointer finger and middle finger)

Carpal tunnel syndrome can affect both your hands. Symptoms are usually worse in your dominant hand (the hand you use the most). Your symptoms may also be worse at night.

Over time, you may slowly lose strength and movement in your hand and wrist. So, it's important to see your doctor if you think you may have carpal tunnel syndrome.

What causes carpal tunnel syndrome?

Carpal tunnel syndrome can be caused by anything that makes the nerves or tendons larger. It can also be caused by things that make the carpal tunnel smaller. This includes:

• a wrist or arm injury, such as a sprain or fracture
• activities that involve repetitive use (overuse) of your wrist and hand, including using vibrating tools
• tendinitis
• a cyst or tumour in the carpal tunnel
• diabetes
• hypothyroidism
• arthritis and rheumatoid arthritis
• being overweight

Carpal tunnel syndrome is also common in pregnancy. During pregnancy, the body holds more fluid, which can cause swelling. This can affect your carpal tunnel. Carpal tunnel syndrome usually goes away after giving birth.

Sometimes, carpal tunnel syndrome just happens without any obvious cause.

Risk factors

Some people are more at risk of developing carpal tunnel syndrome, such as:

• people aged between 40 to 60 years
• females

When should I see my doctor?

If you have symptoms of carpal tunnel syndrome, see your doctor. They can:

• rule out any other conditions
• give you treatment to relieve your symptoms and prevent them from getting worse

When to seek urgent care

If you have carpal tunnel syndrome and develop any of the following symptoms, seek medical help urgently:

• weakness in the arm
• changes in sensation (feeling)
• pain that is getting worse or is severe

How is the cause of carpal tunnel syndrome diagnosed?

Your doctor will ask about your symptoms.

Your doctor may also request tests to rule out other conditions, such as rheumatoid arthritis and hypothyroidism. You may then have tests to see how quickly the median nerve passes messages through the carpal tunnel.

They may also do x-rays, particularly if you:

• have injured or broken your wrist
• have bone changes

How is carpal tunnel syndrome treated?

Treatment for carpal tunnel syndrome depends on its cause. These can include:

• avoiding activities that cause symptoms
• wearing a wrist brace (also called a splint) to keep your wrist straight, especially at night
• treating the medical condition that may be causing your symptoms
• physiotherapy

Medicines for carpal tunnel syndrome

These can include:

• anti-inflammatory medicines to ease the pain
• corticosteroid injections into the wrist

Sometimes carpal tunnel syndrome resolves on its own. If you are pregnant, your carpal tunnel syndrome should go away once you have your baby.

Other treatment options

Surgery for carpal tunnel syndrome is usually only considered when:

• your symptoms are severe
• your symptoms have not improved, or have got worse
• other treatments don't work

This surgery is called carpal tunnel release. It involves cutting the ligament that helps form the carpal tunnel. This gives more space for the median nerve and relieves pressure.

Can carpal tunnel syndrome be prevented?

To prevent carpal tunnel syndrome, you can modify your activities to avoid overusing your hands or wrists.

If you know you will be using your hands a lot, wear a wrist splint 1 to 2 nights before the activity.

If you have symptoms, see your doctor. They can help you get early treatment to prevent complications of carpal tunnel syndrome.

Complications of carpal tunnel syndrome

If carpal tunnel syndrome is left untreated, your symptoms can get worse and lead to permanent damage. The muscles in your hand may become weak. This can make it harder to move your arm and hold objects.

It's important to get treatment as soon as possible.

Resources and support

For more advice call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.