Carpal Tunnel Syndrome
Carpal Tunnel Syndrome occurs when there is increased pressure around the nerve called Median nerve in the carpal tunnel located in the palm of your hand. This nerve controls the feelings to the thumb, index and middle fingers. It also controls the muscles at the base of the thumb.
Carpal tunnel is a space at the base of the palm, which is surrounded on three sides by the bones of the wrist and on the front by a thick ligament called the carpal ligament, which completes the tunnel. Nine tendons on their way to the fingers and the thumb and a nerve called the median nerve occupy this tunnel. Carpal Tunnel syndrome is caused when the size of the tunnel is smaller or when the tendons are inflamed. This put the nerve under increased pressure resulting in the symptoms.
Who gets Carpal Tunnel Syndrome?
Carpal Tunnel Syndrome is very common in the general population and it is estimated that one person in ten will probably develop symptoms of carpal tunnel syndrome during his or her lifetime. It is a common problem with pregnant and middle-aged women.
People in certain occupations that require vigorous and repeated use of hands, fingers and wrists are at greater risk of developing this condition. Individuals with diabetes, underactive thyroid and rheumatoid arthritis get this condition because of thickening and inflammation of the tendons.
Pressure on the median nerve may also be due to a fracture of the wrist or the forearm bones causing swelling and direct pressure on the nerve.
In most cases however a specific cause cannot be identified.
The symptoms of carpal tunnel syndrome include pins and needles and tingling sensations in the thumb, index and the middle fingers, and often on the middle finger side of the ring finger. Typically only the fingers are numb but sometimes the whole hand and even the forearm may feel numb. The symptoms are usually worse at night, which may cause the patient to waken from a sound sleep. Some common tasks can also aggravate the symptoms such as driving a car, holding a telephone, reading a newspaper or any activity that involves repetitive grasping etc. The hand or wrist may be painful. Use of the thumb may be limited or impaired. Some patients tend to drop objects.
Often the condition involves both hands but one side may be worse than the other.
The condition is diagnosed after listening to the symptoms and examination of the hands. The diagnosis can be doubly confirmed by electrical test called Nerve Conduction tests and Electromyography. This is not always necessary and is used when the diagnosis is in doubt. The test identifies a reduction in speed of conduction of impulse through a nerve across a segment that is trapped or under pressure.
Treatment of carpal tunnel syndrome is fairly simple and effective. In some patients with mild symptoms of short duration, rest, avoidance of strenuous activity and a wrist splint especially worn at night may keep the symptoms under control. A cortisone injection may also be given to reduce the swelling of the tendons within the carpal tunnel.
For most patients, the treatment is surgery. This is to expand the carpal tunnel to relieve pressure on the median nerve. The operation is called Carpal Tunnel Release. This is performed under local anaesthetic as a day case. The strong carpal ligament on the front of the wrist is divided.
Surgery is highly effective and provides immediate and complete relief of symptoms in over three-fourth of the patients. There is some relief of symptoms in almost all the patients. Risks of surgery are minimal but may include infection and nerve damage.
What to Expect
After surgery your hand will be wrapped in a bulky dressing. You will be discharged home when you are comfortable and your fingers are warm and pink. Once the effect of local anaesthetic wears off you may require painkillers.
You may be provided with a splint for your wrist to use in the first two weeks after surgery.
The dressing can be reduced after 48 hours to a small sticky plaster. You can start moving your fingers as early as you can to avoid swelling and stiffness.
The stitches are removed on about the tenth day after surgery.
The wound may remain red and sensitive to touch for three to four months. Some use of the hand is usually possible within the first week and normal use once the stitches have been removed. Strenuous activity may not be possible for up to four weeks.