Around seven per cent of women and one per cent of men suffer from carpal tunnel syndrome in the UK ⁽¹⁾. The condition can occur at any age, but tends to affect those in their 40s and 50s ⁽¹⁾. Carpal tunnel syndrome causes pain, tingling or numbness in the thumb and fingers of your hand caused by a trapped nerve and the sufferer will be unable to grip items, making many everyday tasks, such as driving, difficult. It can also disrupt sleep.

What is carpal tunnel syndrome?

The carpal tunnel is a narrow space at the front of the wrist through which tendons and nerves pass. These tendons allow the fingers and wrist to bend.

When the tendon swells, sometimes due to overuse, there is very little space in the tunnel for them to expand, and in some people this expansion causes carpal tunnel syndrome, when the tendons compress the median nerve, which runs near the tendons.

The compression causes numbness and tingling and affects nerve impulses, so it may be difficult to grip objects, such as cutlery or pens.

How is it diagnosed?

If you suspect you may have carpal tunnel syndrome, your GP will be able to diagnose your condition. Your doctor may do the following tests:

• Tap the inside of your wrist. If this causes tingling it may indicate that the nerve is being pressured
• If the tapping causes a stinging or shock sensation to your fingertips this may show that the median nerve is not functioning correctly
• A nerve test will asses how well your nerve is conducting electronic signals
• Electromyography (EMG) is a muscle test to find out whether a muscle disorder is causing the tingling or numb sensation. It involves inserting a fine needle into the nerve to measure the electrical activity of your muscle at rest and when under pressure
• A blood test will be carried out to ensure you don't have a thyroid gland problem

How is it treated?

If you have been diagnosed with carpal tunnel syndrome, you may not need an operation immediately. Conservative treatment may be considered first:

• Splints to keep your wrists in a position that maximises room in the carpal tunnel. You will wear them at night, but you can wear them during the day if needed
• Non-steroidal or anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, to reduce inflammation and relieve pain. Patients with asthma should not take NSAIDs
• Oral corticosteroid drugs to lower inflammation and reduce symptoms. These drugs cannot be taken for a long time due to side effects. If you have diabetes, you will not be able to take them
• Ultrasound treatment relieves symptoms in some people. How it works is not fully understood and it may not be provided by all NHS trusts
• Wrist and finger exercises to relieve the pressure on the median nerve. There is little research to support whether such exercises are effective, so ask your GP or physiotherapist for advice

If conservative treatment does not work, you may be advised that you need an operation to relieve the pressure on the nerve. The operation takes around 15 minutes.

Carpal tunnel release operation

An operation on the carpal tunnel is relatively straightforward and requires only a local anaesthetic, which means that the area being operated on is numbed, and you will be awake during the operation.

The affected arm will have an antiseptic solution applied to it and will then be wrapped with a tight or elasticated bandage. This squeezes the blood out of the arm, so that the affected area is free of it.

A small cut is then made in the crease of the wrist, the skin is held back by small retractors to expose the carpal tunnel roof, called the fascia. A small incision is made in the fascia to separate the edges, which will be held back by nylon stitches.

The hand is then bandaged, although the fingers and thumb are left free to move. A new fascia will grow over the following few weeks, enlarging the carpal tunnel area, relieving the symptoms.

You may be prescribed painkillers for the first day or so after the operation, and your arm may be in a sling to provide support and keep it stable. After about two days you will be advised to remove the sling. The stitches will be removed after ten days.

After a year, about nine in 10 people who had surgery said they were better and the improvement lasted for at least 18 months ⁽²⁾.

After the operation:

• Let your workplace know that you will need around three days of rest from your duties
• Massage the scar twice a day with moisturising cream to alleviate sensitivity
• Keep moving your fingers to encourage good circulation
• You may need around six weeks' rest from sport, particularly contact sport
• Once your stitches have been removed you will be able to go swimming, which will help with the flexibility of the wrist
• Normal activities, such as driving, can be resumed as soon as you feel comfortable doing so

Tips to prevent carpal tunnel syndrome developing:

• Stretch your palms and wrists at least once every hour to get the blood circulation flowing
• Do not bend your wrists when using a keyboard - a support pad may help
• Keep the computer mouse close to your body
• Avoid making repetitive movements, such as answering the phone with the same hand or holding your bag in the same hand

Infolinks:

• Arthritis Research Campaign