Carpal tunnel syndrome

Carpal tunnel syndrome (CTS) is when a nerve in your wrist is compressed (squeezed). It’s caused by pressure on the nerve. You may get tingling, numbness, pain, and weakness in your hand. Carpal tunnel syndrome can sometimes get better on its own, but there are also treatments that can help.

About carpal tunnel syndrome

The median nerve is a nerve in your wrist which controls the feeling in your thumb, index, middle, and half of your ring finger. It also controls muscles in your thumb.

Your median nerve runs through a narrow channel in your wrist called the carpal tunnel. The channel is formed from your wrist bones and a tough band of tissue known as the transverse carpal ligament, which is on the top. Anything that reduces the space or increases the pressure in your carpal tunnel can cause carpal tunnel syndrome.

Carpal tunnel syndrome affects people of all ages, but it’s more common in people aged between 40 and 60. It’s also more common in women.

Causes of carpal tunnel syndrome

In many people, carpal tunnel syndrome causes are unclear. It’s likely to be due to several things. Risk factors for developing carpal tunnel syndrome include:

• obesity
• health conditions such as diabetes or an underactive thyroid
• pregnancy – this may be due to the hormonal changes and fluid retention
• injury to your wrist, such as a break (fracture)
• repeated activities that put your wrist in an unnatural position – either bending or twisting it, for example
• an inflammatory health condition, such as rheumatoid arthritis
• a tumour or growth that presses on your nerve or makes your carpal tunnel narrower

Symptoms of carpal tunnel syndrome

Carpal tunnel symptoms tend to affect your thumb and fingers (apart from your little finger). Symptoms include:

• numbness
• a tingling feeling or pins and needles
• weakness and finding it difficult to grip
• pain or a burning feeling in your wrist, fingers and forearm

Carpal tunnel syndrome can affect both hands, or just one. It can start to affect your whole hand and may also spread up your arm. Your symptoms may be mild at first, but they may gradually get worse If your carpal tunnel syndrome is severe, you may have symptoms all the time and your muscles may become weak.

You can get carpal tunnel symptoms at any time but they’re often worse at night and may wake you up. When you wake up, you might find it difficult to stretch or flex your fingers.

Certain activities may also trigger your symptoms in the day. For example, holding a book, driving, or DIY.

Your carpal tunnel syndrome symptoms may feel better if you shake your wrist or change its position.

If you have any of these symptoms, contact your GP for advice.

Diagnosis of carpal tunnel syndrome

Your GP will ask you about your symptoms and your medical history. They’ll want to know when you get symptoms, what triggers them, and how they affect your daily life. They’ll examine your hands, as well as your elbow, shoulder, and neck. They will look for signs of carpal tunnel syndrome, such as swelling, any muscle wasting, and low grip strength. They’ll also check the feelings in your fingers and thumb. They may carry out some special carpal tunnel tests on your hand, such as:

• ask you to bend your wrist and hold in a bent position for around a minute (Phalen's test)
• lightly tap or press over your median nerve on the palm side of your wrist
• press on the ligament over your carpal tunnel in your wrist

Your GP may be able to diagnose carpal tunnel syndrome just by examining you and asking about your symptoms. But sometimes you may need to have some further tests, which may include the following.

• Nerve conduction test. This measures the speed at which signals travel along the median nerve and can show how bad any damage to your median nerve is. In the test, electrodes (sticky pads) are placed on the surface of your skin to stimulate the nerve. How fast the impulse travels to another point is recorded, to show how fast the nerve is working.
• Ultrasound or MRI scan. This allows your doctor to look inside your wrist, and can help to show if there’s any cause for your symptoms.

Self-help for carpal tunnel syndrome

There may be things you can do to manage your symptoms. You may be advised to avoid activities that trigger symptoms, if you can. It can help if you change the way you do these actions or reduce how often you do them.

If you’re overweight, losing excess weight may help to reduce your symptoms.

If you find your symptoms are worse at work, talk to your manager or occupational health department if you have one. They may be able to help with modifications to your workplace or a temporary change to your duties. For example, they may be able to give you a different style of keyboard, or provide you with some wrist rests that could help. You may also need to take regular breaks.

Treatment of carpal tunnel syndrome

You don’t always need carpal tunnel syndrome treatment. For about a third of people, the symptoms improve on their own within about 6 months. This is more likely for younger people and especially if you developed carpal tunnel syndrome when pregnant.

If you have another health condition such as arthritis, and get treatment for it, it may improve your carpal tunnel symptoms.

Wrist splints for carpal tunnel syndrome

Wrist splints can help to keep your wrist straight and reduce pressure on your compressed nerve. This may help with symptoms at night. Your doctor will usually advise you to wear wrist splints at night for at least a month. You can also wear splints during the day, but you may find that they get in the way as you go about your day.

You can buy a wrist splint online or from a pharmacy.

Steroid injections for carpal tunnel syndrome

Your GP may offer you a steroid injection into your carpal tunnel to try and reduce any inflammation around the nerve and relieve the pressure. You may be able to have this at your GP surgery or they may refer you to a specialist for the treatment.

Steroid injections work well for many people but it can take a few weeks to get the full effects. They don’t work for everyone. They can also wear off after a while and your symptoms may come back. If your symptoms do return, you may be able to have another injection but it doesn’t always work.

Carpal tunnel surgery

If your symptoms are severe or other treatments haven’t worked, your GP may refer you to a hand specialist or local musculoskeletal service. They’ll assess you to see if carpal tunnel surgery (also called carpal tunnel release surgery or carpal tunnel decompression) is an option for you.

The procedure involves dividing the ligament in your wrist that forms part of your carpal tunnel to relieve pressure on your median nerve.

There’s a chance that your symptoms may come back after carpal tunnel surgery but this is unlikely. It’s important to talk this over with your doctor before you decide whether or not carpal tunnel surgery is the right choice for you.

Other carpal tunnel syndrome treatments

Exercise therapy

Some people find that hand and wrist exercises can help with carpal tunnel syndrome symptoms. If you see a physiotherapist, they may recommend some of these. Some are simple exercises to improve the strength and flexibility in your wrist. Others, known as nerve glide exercises, aim to help your trapped nerve move more freely. The evidence for how effective these exercises are is limited but it can help some people.

Try and avoid activities (wherever possible) that make your symptoms worse. If you can’t avoid them, take regular breaks.

Complementary therapies

Some people find acupuncture helps to relieve the symptoms of carpal tunnel syndrome. But more evidence is needed to say for sure that it works. Yoga also helps to relieve carpal tunnel syndrome pain for some people, but again, the evidence is limited.

If you decide to try a complementary therapy, check that your therapist is registered with a recognised organisation.