Carpal tunnel syndrome

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 the thumb and most of the next 2 fingers
• controls movement for some of the 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 of 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 the 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 hands. Symptoms are usually worse in the hand you use the most (your dominant hand).

Over time, people with carpal tunnel syndrome might slowly lose strength and movement in their 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 the wrist and hand, including using vibrating tools
• rheumatoid arthritis and other joint disorders or connective tissue disorders
• tendinitis
• fluid retention during pregnancy or menopause
• a cyst or tumour in the carpal tunnel
• diabetes
• hypothyroidism
• abnormal growth of the hands (acromegaly)
• kidney disease with dialysis

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

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

• females aged 40 to 60 years
• people aged over 70 years
• people with arthritis
• people who put on weight rapidly
• people who use their hands repeatedly in their work
• people who are pregnant

Carpal tunnel syndrome is common in pregnancy. During pregnancy, the body holds more fluid, which can cause swelling. This can affect your carpal tunnel.

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

How is carpal tunnel syndrome diagnosed?

Your doctor will ask about your symptoms. You may then have tests to see how quickly the median nerve passes messages through the carpal tunnel.

Your doctor may also request other tests to rule out other conditions, such as rheumatoid arthritis and hypothyroidism. 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.

Treatment options can include:

• treating the medical condition that could be causing your symptoms
• wearing a wrist brace (also called a splint) to keep the wrist straight, especially at night
• ice, elevation, massage
• anti-inflammatory medicines to ease pain
• avoiding activities that cause symptoms
• physiotherapy
• corticosteroid injections into the wrist
• surgery

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

Surgery for carpal tunnel syndrome is only considered when:

• other treatments do not work
• your symptoms have not improved, or got worse

This surgery is called carpal tunnel release. It involves cutting a ligament that helps form the carpal tunnel. This provides 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 have symptoms, see your doctor. They can help you get early treatment to prevent further complications of carpal tunnel syndrome.

What complications can be caused by carpal tunnel syndrome?

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