Carpal tunnel syndrome
What is it?
Carpal tunnel syndrome (CTS) comprises a group of symptoms caused by pressure on the median nerve, which is near the centre of the palm. Pain occurs at the level of the wrist as the nerve passes through the carpal tunnel in the wrist to supply the muscles of the hand.
Why does it occur?
The reason why the nerve becomes squashed as it passes into the wrist is unknown. A multitude of conditions are linked, but don’t always lead to the development of carpal tunnel syndrome. Some of these include pregnancy, rheumatoid arthritis, thyroid diseases and diabetes. Trauma to the wrist through fracture or repetitive strain may also precipitate symptoms.
What are the symptoms?
These can include tingling or pain in the affected hand and fingers, that starts gradually but can progress to numbness and wasting of the muscles in the palm of the hand that are supplied by the median nerve. Patients typically suffer with their symptoms at night or after certain repetitive movements, such as typing or the heavy use of a touchpad. Some patients find relief by shaking the hand, or holding it over the side of the bed at night.
How is it diagnosed?
Your consultant will usually be able to establish whether you are suffering from carpal tunnel syndrome after taking a history and examining your hand and wrist. However, in some patients the symptoms are ambiguous and nerve conduction studies (NCS) are needed. This test measures how quickly your nerves relay information up and down your arm, which is reduced in those with carpal tunnel syndrome.
How is it treated?
Those suffering at night often find relief wearing a removable splint. This keeps the wrist straight while you sleep, avoiding compression of the nerve. Steroid injections have been beneficial in those patients suffering with nerve compression as a result of tissue inflammation within the carpal tunnel. The injected hydrocortisone is a strong local anti-inflammatory medication, acting to reduce swelling and subsequently pressure on the nerve. This is particularly useful in transient CTS which sometimes develops during pregnancy.
This involves a small operation under local anaesthetic which acts to free up the nerve as it passes through the wrist and into the hand. Following the procedure any night tingling and pain should settle quickly, but numbness in the fingers may take weeks or months to disappear depending on the severity of your CTS.
The One Orthopaedics team specialists
Consultant Hand Surgeon, FRCS
Consultant Orthopaedic Specialist FRCS (Tr & Orth)