Carpal tunnel syndrome

Carpal tunnel syndrome is a relatively common condition that can cause tingling, numbness and pain in the hand and fingers. It is caused by a trapped nerve in the wrist.

Carpal tunnel syndrome (CTS) can occur at any age and is most common where patients perform repetitive tasks with the hand and wrist (using a keyboard for example). One or two hands may be affected

Carpal tunnel syndrome causes numbness, a tingling sensation, or sometimes pain in the arm, hand and fingers, usually affecting the thumb, index finger and middle finger. These symptoms usually start gradually and are often worse at night, sometimes interrupting sleep.

Carpal tunnel syndrome occurs when the median nerve in the front of the wrist becomes trapped within the carpal tunnel. This is the canal in the wrist which carries all the hand tendons; when these become swollen, the median nerve is squeezed. The nerve controls movement and sensation in the hand; when trapped it causes pins and needles or pain in the hand and fingers.

In most cases the causes of carpal tunnel syndrome are not clear. There are a number of factors that increase the likelihood of contracting carpal tunnel syndrome. These include; a family history of the condition; pregnancy (around 50% of pregnant women develop the condition caused by fluid retention); injury to the wrist that narrows the carpal tunnel; repetitive or strenuous work involving the hands, or working with vibrating machinery; rheumatoid arthritis; and diabetes

Carpal tunnel syndrome is more common in women, and you’re more likely to suffer as you get older.

The key symptoms of carpal tunnel syndrome are tingling, numbness and pain in the hand and fingers. Either hand, or both hands, may be affected. Often both hands are eventually affected. There may be an ache which extends up your arm, a weakness in your hand and difficulties in gripping objects.

The symptoms tend to develop gradually at first and are usually worse during the night or first thing in the morning.

The fingers most commonly affected are the thumb, the index finger, the middle finger and half of the ring finger. There may also be pain, tingling or aching in other areas of the hand, wrist or arm. You may experience a burning or prickling sensation (paraesthesia) in the hand or dry skin, swelling or changes in the skin colour of the hand. The area may become less sensitive to touch (hypoaesthesia) and there may be some weakness or wasting away (atrophy) of the muscles at the base of the thumb.

Symptoms can include:

  • tingling, numbness and pain in the hand and fingers
  • dull ache or discomfort in the hand, forearm or upper arm
  • a burning, prickling sensation (paraesthesia) in the hand
  • dry skin, swelling or changes in skin colour of the hand
  • being less sensitive to touch (hypoaesthesia)
  • weakness or wasting away (atrophy) of the muscles at the base of the thumb

Your doctor can usually diagnose carpal tunnel syndrome by examining your hand and wrist, and discussing your symptoms.

You may be referred to a specialist to carry out further tests to determine the severity of the condition. For example, you may undergo a nerve conduction test which measures how fast signals travel through your nerves and can determine whether there is any damage to your nerves. You may also have an ultrasound scan which produces an image of the nerve itself which can help to determine the correct course of treatment.

A blood test may be suggested to rule out any underlying causes of carpal syndrome including rheumatoid arthritis, diabetes or an underactive thyroid gland (hypothyroidism).

What next?

If you are suffering with a suspected condition, you should seek the advice of your doctor who will be able to refer you to Benenden Hospital for diagnosis and treatment.

There are four ways to access treatment at Benenden Hospital which include self-funding, using private medical insurance or your Benenden membership, or through the NHS e-Referral scheme.