This is a very common condition which is predominantly seen in women. At the base of our wrist we all have a ligament called transverse carpal ligament (see the figure below). It spreads across the wrist like a sheet. On the other side of the wrist are our small bones of the hand. Thus between the bones and the ligament a tunnel is formed which is known as the carpal tunnel. The tendons and muscles which move our fingers pass through this tunnel on their way from the forearm to the fingers. Also a very important nerve travels through this tunnel and is known as the median nerve (see figure below).

A patient starts complaining of pain along these three fingers accompanied by numbness initially. These symptoms occur typically at night and disturb sleep. Symptoms if untreated gradually increase and start as soon as the patient achieves a position of the wrist where the tunnel gets crowded e.g. holding a telephone receiver for a long time. Gradually y the numbness persists throughout the day. If untreated it gradually leads to weakening of the grip and the patient may notice that things keep dropping from his hand.

The prominence below the thumb seen normally starts to disappear and the base of the thumb appears flat and shriveled.

Any condition which causes crowding of the carpal tunnel will lead to these diseases. Here are a few common causes

A fracture at the wrist : A wrongly aligned fracture at the wrist can cause the tunnel to become very narrow causing symptoms. Typically a patient starts getting symptoms after the plaster is removed.

Pregnancy : There is a lot of water retention during pregnancy which can lead to overcrowding the tunnel and many pregnant ladies suffer during their term. Fortunately the retention subsides on it's own after the birth of the child and hence no treatment is required for this condition. Rarely the numbness can be very severe and in such cases a short course of diuretics (drugs which reduce water from the body) can be used. However these drugs should be taken only after consulting your doctor.

Thyroid diseases : Like pregnancy the thyroids disorders also lead to a lot of water retention and can cause this condition. A proper control of thyroid medication can help some where as a large majority needs attention of an orthopedic surgeon.

Idiopathic : It is a large group of patients where any specific cause is not found and is termed Idiopathic.

Rare causes : e.g. a cyst under the carpal ligament or a tumor of the nerve just beneath the ligament.

Diagnosis

The diagnosis of carpal tunnel is made from the history and clinical examination in most of the cases. To confirm the diagnosis an EMG (electromyogram) is a must. This test is performed in all major hospitals and is not very expensive. In rare instances your doctor may advise you to undergo a MRI of the wrist.

Treatment

The initial treatment consists of splinting the wrist using a splint at night. In certain cases anti-inflammatory drugs or even diuretics are prescribed. Some patients may require a steroid injection in the tunnel.

Those who do not respond to these simple remedies or have come very late need to get an EMG done. The EMG tells your treating doctor about how badly the nerve is damaged due to compression. If the report indicates a severe compression then a surgery is recommended.

The surgery can be done under local anesthesia. It involves cutting the transverse ligament which lies just beneath the skin. It is a minor procedure and last for 15 minutes. The patient need not be hospitalized for the same.

After the surgery the patient is asked to use the splint for some time. Stitches are removed between 7 to 10 days. Patients can get back to their routine work by 2 weeks easily. There are usually no complications associated with this surgery.