Carpal tunnel syndrome is a common condition that causes pain, numbness, and weakness in the hands and wrist. It occurs when there is increased pressure on a nerve called the median nerve. This nerve provides sensation to the thumb, index and middle fingers, and to half of the ring finger. The small finger (the “pinky”) is typically not affected. The median nerve also provides strength to some of the muscles at the base of the thumb.
Anything that squeezes or irritates the median nerve in the carpal tunnel space may lead to carpal tunnel syndrome. A wrist fracture can narrow the carpal tunnel and irritate the nerve, as can the swelling and inflammation resulting from rheumatoid arthritis.
Who Is Most Likely To Get Carpal Tunnel Syndrome?
People most at risk are those with jobs or activities that involve repetitive finger use, especially those associated with high force, long-term use, extreme wrist motions, and vibration.
Other things that contribute to the development of carpal tunnel syndrome include:
- Heredity (smaller carpal tunnels can run in families).
- Wrist fracture and dislocation.
- Hand or wrist deformity.
- Arthritic diseases such as rheumatoid arthritis and gout.
- Thyroid gland hormone imbalance (hypothyroidism).
- A mass (tumor) in the carpal tunnel.
- Older age
Signs and Symptoms
Carpal tunnel syndrome symptoms usually start gradually. The first symptoms often include numbness or tingling in your thumb, index and middle fingers that comes and goes. Carpal tunnel syndrome may also cause discomfort in your wrist and the palm of your hand.
The sensation may travel from your wrist up your arm. These symptoms often occur while holding a steering wheel, phone or newspaper. The sensation may wake you from sleep. Many people “shake out” their hands to try to relieve their symptoms. The numb feeling may become constant over time.
You may experience weakness in your hand and a tendency to drop objects. This may be due to the numbness in your hand or weakness of the thumb’s pinching muscles, which are also controlled by the median nerve.
As carpal tunnel syndrome becomes more severe, you may have less grip strength because the muscles in your hand shrink. Pain and muscle cramping will also become worse. The median nerve begins to lose function because of the irritation or pressure around it. This leads to:
- Slower nerve impulses.
- Loss of feeling in the fingers.
- A loss of strength and coordination, especially the ability to use your thumb to pinch.
You could end up with permanent muscle damage and lose function in your hand. So, don’t put off seeing a doctor.
How is it Diagnosed?
First, your doctor will discuss your symptoms and medical history and examine you. Next, tests are performed, which may include:
- Tinel’s sign. In this test, the physician taps over the median nerve at the wrist to see if it produces a tingling sensation in the fingers.
- Wrist flexion test (or Phalen test). In this test, the patient rests his or her elbows on a table and allows the wrist to fall forward freely. Individuals with carpal tunnel syndrome will experience numbness and tingling in the fingers within 60 seconds. The more quickly symptoms appear, the more severe the carpal tunnel syndrome.
- X-rays of the wrist may be ordered if there is limited wrist motion, or evidence of arthritis or trauma.
- Electromyography (EMG) and nerve conduction studies. These studies determine how well the median nerve itself is working and how well it controls muscle movement.
How Is It Treated?
The choice of treatment for carpal tunnel syndrome depends on the severity of the symptoms and any underlying disease that might be causing the symptoms.
- Lifestyle changes. If your symptoms are due to repetitive motion, you can take more frequent breaks or do a bit less of the activity that’s causing you pain. Certain stretching and strengthening exercises could help, too. Speak with your doctor.
- The doctor may have you use a splint to keep your wrist from moving and to lessen pressure on the nerves. You may wear one at night to help get rid of that numbness or tingling feeling. This can help you sleep better and give your median nerve a rest.
- Medication. Your doctor may give you anti-inflammatory drugs or steroid shots to reduce swelling.
- If none of the above treatments work, an operation may be an option. Talk with your doctor about it.
There are no proven strategies to prevent carpal tunnel syndrome, but you can minimize stress on your hands and wrists with these methods:
- Reduce your force and relax your grip. If your work involves a cash register or keyboard, for instance, hit the keys softly. For prolonged handwriting, use a big pen with an oversized, soft grip adapter and free-flowing ink.
- Take frequent breaks. Gently stretch and bend hands and wrists periodically. Alternate tasks when possible. This is especially important if you use equipment that vibrates or that requires you to exert a great amount of force.
- Watch your form. Avoid bending your wrist all the way up or down. A relaxed middle position is best. Keep your keyboard at elbow height or slightly lower.
- Improve your posture. Incorrect posture rolls shoulders forward, shortening your neck and shoulder muscles and compressing nerves in your neck. This can affect your wrists, fingers and hands.
- Change your computer mouse. Make sure that your computer mouse is comfortable and doesn’t strain your wrist.
- Keep your hands warm. You’re more likely to develop hand pain and stiffness if you work in a cold environment. If you can’t control the temperature at work, put on fingerless gloves that keep your hands and wrists warm.
- Medicinenet – carpal_tunnel_syndrome
- Mayoclinic – carpal-tunnel-syndrome/symptoms-causes
- my.clevelandclinic.org – carpal-tunnel-syndrome/diagnosis-and-tests
- orthoinfo.aaos.org – carpal-tunnel-syndrome