Carpal Tunnel Syndrome
Overview
Carpal Tunnel Syndrome. The primary symptoms of Carpal Tunnel Syndrome (CTS) are tingling, numbness and discomfort in one or both hands. Most cases affect both hands eventually. The symptoms of CTS most often occur in: the thumb, the index finger, the middle finger, half of the ring finger.
However, the tingling pain can and sometimes often extend outside this area. The symptoms of CTS also tend to develop gradually, and usually, start off being worse at night or early in the morning. Any repetitive actions of the hand or wrist can aggravate the symptoms, as can keeping your arm or hand in the same position for a prolonged period.
OTHER SYMPTOMS
Other possible symptoms of Carpal Tunnel Syndrome include: a dull ache and pain in the hand, forearm or upper arm, a burning, prickling sensation (paraesthesia) in the hand, comparable to pins and needle, dry skin, inflammation or changes in the skin colour of the hand, becoming less sensitive to touch (hypoaesthesia), weakness and wasting away (atrophy) of the muscles at the base of the thumb. In some cases, you may encounter pain that radiates from your hand up to your forearm and elbow.
USING YOUR HANDS
CTS often affects your dexterity, which is the ability to use your hands effectively to carry out certain tasks. You may find you often drop objects, or have difficulty typing or closing buttons.
CAUSES
The symptoms of carpal tunnel syndrome (CTS) are generated by crushing (compression) of the median nerve at the wrist.
The median nerve is responsible for two principal functions:
carrying physical feelings such as your sense of touch from your hand to your brain
carrying nerve signals from your brain to your hand, regulating movement
Any stress on the median nerve can disrupt the nerve signals, affecting your sense of touch and hand movements. The median nerve can become squashed if the tissues inside the carpal tunnel become swollen or the carpal tunnel narrows over time.
INCREASED RISK
In most cases, it is not known what causes the median nerve to become compressed, although some things increase the risk of developing CTS.
These include:
a family history
certain health conditions, such as diabetes, an underactive thyroid gland or rheumatoid arthritis
pregnancy
certain injuries to the wrist
certain activities
These risk factors are outlined below.
FAMILY HISTORY
Studies have shown there's a genetic link to carpal tunnel syndrome. This means you may have an increased risk of developing it if others within your family have the ailment or have had it in the past. About one in four people with carpal tunnel syndrome have a close relative, such as a parent, brother or sister, who also has the condition. It is not fully known how and why the ailment is passed on through families.
HEALTH CONDITIONS
Certain health conditions appear to increase your risk of developing carpal tunnel syndrome.
These include:
diabetes – a chronic (long-term) condition caused by having too much sugar (glucose) in the blood
any kind of arthritis – a condition where the joints become painful and inflamed
hypothyroidism – an underactive thyroid gland
obesity in young people
some drugs used to treat breast cancer – such as exemestane (Aromasin)
Carpal tunnel syndrome can also develop when a person has an abnormal wrist structure, such as an oddly narrow carpal tunnel. It can also be a result of cysts, growths or swellings in the carpal tunnel.
PREGNANCY
CTS is common during pregnancy, although the exact cause is not known. Many cases resolve after the baby is born. It is not known whether women who have CTS during pregnancy are at greater risk of forming the condition in later life. CTS is also common in women around the time of the menopause.
INJURIES
Carpal tunnel syndrome can sometimes occur after a hand injury, such as a sprain, fracture or crush injury. This is because the swelling places stress on the median nerve. Also, these types of injuries can change the natural shape of the bones and ligaments in the hand, leading to increased stress on the median nerve.
CERTAIN ACTIONS
Certain actions may trigger the development of carpal tunnel syndrome. These tend to involve strenuous grip, bending the wrist repetitively (flexion) and exposure to vibration.
Examples include: playing a musical instrument, assembly packing, work that involves manual labour, work with vibrating tools, such as pneumatic hammer.
Further study into the link between work-related hand use and carpal tunnel syndrome is required to ascertain how important these types of activities are in causing the condition. Although typing is often considered a possible cause of carpal tunnel syndrome, carpal tunnel syndrome is less common in people who type all day than those who carry out more strenuous activities.