Carpal Tunnel Syndrome
What is carpal tunnel syndrome?
Carpal tunnel syndrome is a common condition where there is increased pressure on one of the main nerves to the hand (the median nerve). This nerve passes through a space in the wrist called the Carpal Tunnel together with nine tendons. Compression of the nerve can cause symptoms in the hand such as uncomfortable ‘pins & needles’, burning sensations, or numbness and weakness in more severe cases. Occasionally the discomfort may extend from the hand into the forearm, and worsen with some manual activities such as driving or typing. Symptoms can commonly wake patients from sleep at night.
What is the cause?
In the majority of cases there is no known cause. There are several conditions which may contribute to or be associated with its onset such as Diabetes, pregnancy, thyroid disorders, rheumatoid disorders and wrist trauma.
Diagnosis can often be made from the clinical history (the account of events and symptoms from the patient) and the clinical examination. Where the diagnosis is not clear, nerve conduction studies are useful. These tests measure how fast the nerve conducts its electrical signal. With carpal tunnel syndrome, the nerve conducts its electrical signal more slowly at the site of compression. These tests can be organised by either your GP or Surgeon.
The decision as to which treatment is most suited to you is influenced by the severity of your symptoms. For less severe symptoms, the following options may be used:
- Wrist splints: A wrist splint worn at night can give some relief of mild night-time symptoms by preventing the hand and wrist from adopting positions that put pressure on the nerve.
- Cortisone injection: This is a steroid injected into the carpal tunnel used to confirm the diagnosis and to reduce inflammation. It improves symptoms initially in over 60% of patients which may be sufficient to allow the compression to resolve where there is an identifiable cause (e.g. pregnancy or mild trauma). However, only around a third of patients have long-term improvement. The effect of the injection tends to be better in younger patients.
For more severe cases, surgery (an operation) to reduce the pressure on the medial nerve may be required. This is known as a Carpal Tunnel Decompression.
For the majority of patients, most symptoms are reversible. However, if there has been long-standing or severe compression to the nerve, symptoms of numbness and weakness may take longer to resolve, and may not resolve fully.
Carpal Tunnel Decompression
This can be performed as either an open procedure or an endoscopic (keyhole) technique. In most circumstances an open technique is preferable. This is performed under Local Anaesthetic as a Day Case procedure. Surgery aims to relieve pressure on the Median Nerve by dividing the roof of the carpal tunnel (transverse carpal ligament). At the end of the procedure the incision is stitched with fine sutures and the hand put in a large bandage. This is usually removed after 48-72 hours.
You should be fit to go home soon after the operation. The anaesthetic will wear off after approximately 6 hours. Simple analgesia usually controls the pain and should be started before the anaesthetic has worn off. The bandage you will have on initially may make it difficult for you to eat and wash yourself, so you may need to arrange assistance.
You should keep your hand/arm elevated whenever possible over the first 48 hours after surgery. While sitting this is best achieved by placing your arm on pillows above the level of your heart. Light use of the hand is encouraged to maintain finger mobility.
You will have a bandage or dressing on for about 2 weeks after the operation. Some wounds are closed with dissolvable stitches, which can take up to a month to disappear. Any non-dissolving stitches will need to be removed at 10-12 days following the operation. Until this time you should keep the wound clean and dry, your fingers and thumb moving, and the hand elevated when possible to reduce swelling and throbbing.
Once the wound is well healed the scar and surrounding tissues should be massaged using small circular movements to reduce the sensitivity. You can rub simple hand cream or pure vegetable oil into the scar to soften it, for five minutes several times a day. There is usually no need for physiotherapy.
Returning to work will depend on your circumstances and type of work. If your job is light you may return after 2-3 weeks, but if it is heavy/manual you may require 6 weeks or more off work.
You should not drive for at least 2 weeks following your operation. You need to be able to perform an emergency stop safely and use the gear stick, steering wheel and hand brake without difficulty.