What is it?
One of the main nerves supplying the hand with feeling and power is called the median nerve. This nerve passes into the hand through a passage in the wrist called the Carpal Tunnel. Sometimes the median nerve can become squeezed inside this Tunnel. This is called Carpal Tunnel Syndrome. Sufferers often notice strange feelings in their fingers, often pins and needles or numbness. There may be pain at night. The hand may become weak and in severe cases gripping small objects can be difficult.
What causes it?
In most cases we do not know why people get this problem. Sometimes we can trace the cause to a broken wrist, pregnancy, thyroid trouble or types of arthritis. Some other diseases can mimic Carpal Tunnel Syndrome, including diabetes and arthritis of the neck. Some types of work, vibrating tools and even tight gloves can all make the feelings of Carpal Tunnel Syndrome worse.
How do you know that I have it?
I may be able to diagnose your Carpal Tunnel Syndrome in the clinic without special tests. Sometimes I may need to do some tests. I occasionally ask to do blood tests, X rays or scans, but the test I do most commonly is called a nerve conduction study (NCS). You usually need a Neurophysiology appointment for this test. When I get the results of the NCS test I see you again. An injection of steroid into the wrist is sometimes used when the diagnosis is difficult or to give rapid pain relief when the pain is very severe.
What are nerve conduction studies?
A nerve conduction study is a test to measure the ability of a nerve to transmit messages (electrical impulses) to and from the brain. If a nerve is compressed it will not be able to transmit the impulse normally. As well as the median nerve, other nerves are tested at the same time to be certain that your symptoms are not the result of some other cause.
Can it be successfully treated without surgery?
Yes. Some cases go away after a while without any treatment at all. Milder cases can be well treated by a wrist splint. Splints work well at night or during work. Water tablets work in some cases. You get these from your GP.
What if these treatments do not work?
In more severe cases these treatments are often only helpful for a short while. Fortunately there is a reliable operation, which cures Carpal Tunnel Syndrome in over 90% of cases. This operation is called a Carpal Tunnel decompression.
What happens in Carpal Tunnel decompression?
Patients usually have the operation as a day case. This means they come to hospital, have the operation and go home all in the same day. They usually do not have to go to sleep. Instead, the palm of the hand is numbed with an injection. An inflatable bandage (like a blood pressure cuff) is put round the arm, this is called a tourniquet and it stops bleeding during the operation. A cut is made in the palm and along the roof of the Carpal Tunnel. This takes the pressure off the nerve. The wound is then stitched up and the hand is bandaged. After the operation a sling is provided. This keeps the hand up and cuts down on swelling. It is best to keep the hand in the sling when upright, or, raised on pillows when lying for the first two days. The bandage is replaced with a large sticking plaster after two days. Using the hand as normally as possible speeds recovery. The hand must be kept clean and dry. Driving is allowed once the dressing is removed. The stitches are taken out at 10-14 days after the operation. The ward staff will arrange this. If there have been no complications there will be no limits on what you are allowed to do after the stitches are removed.
Time off work is usually 2-7 days for people in light work and 2-4 weeks for people in heavy, dirty work. People working with food are not allowed back to work until the wound is completely healed.
What are the complications of Carpal Tunnel decompression?
Complications are not common. Of these, Infection is the most common. It is usually easily treatable with antibiotics. You may get a collection of blood in the wound called a haematoma. Rarely this has to be removed. Nerves can be injured during surgery. This is extremely rare but serious and is usually treated by surgery to the nerve. Dystrophy is an extremely rare but serious complication in which the whole hand gets very sore and seizes up. It can be treated but recovery can take a long time and the hand may be stiffened at the end. Commonly the scar or the area on either side is tender for some months afterwards. This is normal and will go away. Massaging with moisturising cream will help. If the hand had been weak before surgery the strength may not come back. Most important is to remember that the operation does not work in about one case in ten.