Carpal Tunnel Syndrome
Carpal tunnel syndrome also known as median nerve compression, is a condition which can lead to numbness, tingling or weakness in your hand. It occurs due to a pressure on your median nerve, which runs the length of your arm and goes through a passage in your wrist which is known as the carpal tunnel, ending in your hand. The median nerve controls the movement as well as the feeling of your thumb and movement of all the fingers excluding the little finger.
The anatomy of your wrist, health problems and possibly repetitive hand motions, can contribute to this condition. With proper treatment, one can get rid of the tingling and numbness, as well as restore the proper function of their hand.
Symptoms of carpal tunnel syndrome may include:
- Burning, tingling, itching, numbness in your palm as well as the thumb of your index and middle fingers.
- Shock-like feelings which move into your fingers
- Weakness in your hand making it difficult to hold objects
- Tingling sensation which moves up into your arm
There are several other signs you may notice, such as your fingers ‘falling asleep’ and becoming numb at night. It happens as a result of how you hold your hand while you are sleeping.
In the morning, you might be waking up with numbness as well as tingling in your hands running all the way to your shoulder. During the day, your symptoms may flare up while you are holding an object with the wrist bent, when you may be driving or reading a book.
Initially, you might feel better after you shake your hands, but eventually after some time, it might not make the numbness go away. As this syndrome gets worse, you might have less strength in your grip as well, since it causes the muscles in your arm to shrink. You’ll be experiencing more pain as well as muscle cramping.
Due to the irritation or pressure around it, your median nerve is unable to work the way it should. This might lead you to slower nerve impulses, less feeling in your fingers, less strength as well as coordination, especially to the ability to use your thumb.
Causes and risk factors
Pressure on the median nerve leads to carpal tunnel syndrome. The median nerve runs from your forearm through a passageway in your wrist to your hand. It provides sensation to the palm side of your fingers and thumb, except the little finger. It also provides the nerve signal for moving the muscles around the base of the thumb.
Anything which squeezes or irritates the median nerve in the carpal tunnel space might lead to carpal tunnel syndrome. A wrist fracture can narrow the carpal tunnel and cause irritation in the nerve, as the swelling and inflammation caused by rheumatoid arthritis.
Mostly, carpal tunnel syndrome has more than a single cause. A combination of risk factors can contribute and lead one to develop this condition.
Several factors exist which are associated with carpal tunnel syndrome and though all of them might not be the direct cause, they can increase the risk of damage to the median nerve.
- Anatomic factors: A wrist fracture or dislocation or arthritis which deforms the wrist’s small bones, may alter the space within the carpal tunnel and put pressure on the median nerve.
- Sex: In women, carpal tunnel syndrome is usually more common. This could be because the carpal tunnel area is relatively smaller in women, as compared to men. Women having carpal tunnel syndrome might also have smaller carpal tunnels, compared to those women who don’t.
- Nerve-damaging conditions: Chronic ailments such as diabetes can increase the risk of nerve damage, including damage to one’s median nerve.
- Inflammatory conditions: Rheumatoid arthritis as well as other conditions having an inflammatory component can affect the lining around the tendons in your wrist, as well as put pressure on the median nerve.
- Obesity: Being obese or overweight also increases the risk of developing carpal tunnel syndrome.
- Medications: According to some studies, there is a link between carpal tunnel syndrome and the use of a drug named anastrozole, which is used for treating breast cancer.
- Body fluid changes: Fluid retention might increase the pressure within your carpal tunnel, which can irritate the median nerve. This is quite common during pregnancy and also during menopause. If your carpal tunnel syndrome is associated with pregnancy, there is a chance that it will get better on its own after the pregnancy.
- Other medical conditions: Menopause, thyroid disorders, lymphedema, kidney failure and certain medical conditions can increase the chances of carpal tunnel syndrome.
- Workplace factors: If you are working with vibrating tools, or on an assembly line, it can require prolonged or repetitive flexing of your wrist. This may create pressure on the median nerve, which can be harmful and may worsen existing nerve damage.
However, these risk factors haven’t yet been established scientifically as direct causes of carpal tunnel syndrome.
Many studies have also evaluated whether there is an association between the prolonged usage of computer and carpal tunnel syndrome. Some evidence suggests that using the mouse for a longer period can lead to problems. However, there hasn’t been enough consistent and reliable evidence to support extensive computer use as a risk factor for carpal tunnel syndrome, although it might cause a different kind of hand pain.
To determine whether you are having carpal tunnel syndrome, your doctor might be asking you to one or more of the following tests.
History of symptoms
Your doctor will need to review the pattern of your symptoms. Sometimes when the median nerve doesn’t provide sensation to your little finger, symptoms in that finger might indicate a problem other than carpal tunnel syndrome. Symptoms of carpal tunnel syndrome usually occur while holding a newspaper of phone or gripping the steering wheel. They tend to occur at night as well and might sometimes wake you up during your sleep. You may also sometimes notice the numbness in the morning, after waking up.
An X-ray of the affected wrist is also sometimes recommended, to exclude other causes of wrist pain such as fracture or arthritis.
Your doctor will be conducting a physical examination, where he will test the feeling in your fingers as well as the strength of the muscles in your hand. In many people, symptoms can be triggered by tapping on the nerve, bending the wrist or simply pressing on the nerve.
Electromyography is used for measuring the tiny electrical discharges which are produced in muscles. Your doctor will be inserting a thin needle electrode into specific muscles to evaluate the electrical activity when muscles contract and rest. This test can help in identifying damage to the muscles which are controlled by the median nerve. It also helps in ruling out other conditions.
Nerve conduction study
Nerve conduction study is a variation of electromyography, where two electrodes are taped to your skin. A small shock is passed through the median nerve in order to see if electrical impulses are slowed in the carpal tunnel. This test can help diagnose your condition, as well as in ruling out other conditions.
Treatment options for carpal tunnel syndrome
Carpal tunnel syndrome should be treated as soon as possible once you start seeing the symptoms. When the illness in the early stages, it might go away after you perform some simple activities.
- Take breaks more frequently to rest your hands
- Avoid any kind of activity which can worsen your symptoms
- Apply cold packs that will help in reducing the swelling
There are other treatment options as well, which include splinting, medications as well as surgery. Splinting and other conservative treatments are likely to help you if your symptoms are mild and moderate and they come and go for less than ten months. You will need to see a doctor if you are having numbness in your hands.
If the condition is diagnosed early, you can go for nonsurgical methods such as:
Nonsteroidal anti-inflammatory drugs (NSAIDS)
Your doctor might inject your carpal tunnel with a corticosteroid such as cortisone to help in relieving the pain. Your doctor might also sometimes use an ultrasound to guide these injections. Corticosteroids can help in decreasing inflammation as well as swelling, which relieve pressure on the median nerve. Oral corticosteroid, however, are not considered to be as effective as corticosteroid injections for treating carpal tunnel syndrome.
If rheumatoid arthritis or other such inflammatory arthritis is the cause of your carpal tunnel syndrome, then treating your arthritis can help in reducing the symptoms of carpal tunnel syndrome. However, this is yet to be proven.
Surgery might be appropriate if your symptoms are severe and/or not responding to other kinds of treatment.
Carpal tunnel surgery is performed to relieve pressure by cutting the ligament pressure on the median nerve.
The surgery might be performed with two different techniques:
During endoscopic surgery, your surgeon uses a device resembling a telescope, with a small camera attached to it, to see the inside your carpal tunnel. The surgeon will next cut the ligament through one or two small incisions in your hand or wrist. Some surgeons might also use ultrasound instead of a telescope for guiding the tool which cuts the ligament.
Endoscopic surgery usually results in less pain compared to open surgery in the first few days or weeks after surgery.
During open surgery, your surgeon makes an incision in the palm of your hand as well as over the carpal tunnel and cuts through the ligament for freeing the nerve. It is best that you discuss the benefits and risks of each technique with your surgeon before the surgery is performed.
It is also important to note that the surgery possesses a few risks which include:
- Incomplete release of the ligament
- Scar formation
- Wound infections
- Injuries to your nerves or blood vessels
During the healing process after your surgery, the ligament tissues will gradually grow back together and allow more room for the nerve. Usually, this internal process takes several months, but the skin will heal in just a few weeks.
Once the ligament has healed, your doctor might gradually encourage you to use your hand and you can gradually return to using your hand normally like before. If your symptoms were severe, they might not go away completely after the surgery.
You should also keep in mind to avoid forceful hand motions or extreme wrist positions.