Do your thumb and fingers tingle, burn or feel numb? You could have carpal tunnel syndrome, which is caused by a pinched nerve in your wrist, says UNC Health orthopedic surgeon Jeremy J. Miles, MD.
“There’s a nerve that provides feeling to your thumb, index and middle fingers,” he says. “It passes through the carpal tunnel, along with nine tendons.”
The carpal tunnel is a narrow passageway, about an inch wide. The floor and sides of the tunnel are formed by small bones of the wrist. The roof of the tunnel is a thick ligament, called the transverse carpal ligament.
“The main function of this ligament is to hold the tendons and nerve down on the bones,” Dr. Miles says. “If it holds too tightly, then the nerve gets pinched.”
You can get carpal tunnel syndrome in one or both hands, at the same time or different times.
Who Is at Risk for Carpal Tunnel Syndrome?
The risk for getting carpal tunnel syndrome increases with age, Dr. Miles says. Most cases occur in people older than 40, and it’s rare in people younger than 20.
Between 1 and 3 people out of every 1,000 develop carpal tunnel syndrome each year, and it affects more women than men.
Causes of Carpal Tunnel Syndrome
Swelling due to injuries, arthritis or tendinitis can squeeze the nerve and tendons in the carpal tunnel, Dr. Miles says. Injury or trauma to the wrist also may cause the sudden onset of carpal tunnel syndrome, he says, but typically the symptoms come on gradually.
Pregnancy sometimes causes women to experience swelling, including in their hands, which can lead to carpal tunnel syndrome. Also, diabetes, obesity and thyroid gland imbalances are associated with carpal tunnel syndrome. Heredity plays a role, too, as narrow carpal tunnels can run in some families.
Sometimes, repetitive hand and wrist motions over time may aggravate the tendons in the wrist and cause swelling. Doing activities that involve extreme flexing or extending the wrist for a prolonged time, such as when driving, holding a phone or reading a book, can also cause it.
Symptoms of Carpal Tunnel Syndrome
Symptoms of carpal tunnel syndrome usually come on gradually, Dr. Miles says, and often come and go at first. They may include:
- Numbness, tingling, burning and pain
- A shock-like sensation radiating to the thumb and fingers
- Weakness in the hand, making it difficult to button clothes or hold onto objects
“Patients tell me the symptoms often awaken them from sleep, or they feel it first thing in the morning,” Dr. Miles says.
Symptoms usually are in the thumb, index and middle fingers, he says, but not in the pinkie finger. “Sometimes the ring finger is involved,” he says. “Sometimes it’s not.”
If you experience symptoms in your ring and pinkie fingers, you might have a pinched nerve elsewhere, but this is not typical of carpal tunnel syndrome.
Treating the Symptoms of Carpal Tunnel Syndrome
If you have symptoms of carpal tunnel syndrome, consider taking a break from activities that hold your wrist bent for a long time, such as driving or working at a computer, to relieve pressure on the nerve.
If symptoms persist, you could try a wrist splint or carpal tunnel brace, especially at night.
“When your wrist is bent, your nerve is kinked,” Dr. Miles says. “When it’s straight, there’s less pressure. Most of us sleep with our wrists bent, so wearing a brace can help minimize symptoms at night.”
If these steps don’t relieve your symptoms, it’s time to seek professional help. Your primary care physician may refer you to a hand surgeon or other doctor who specializes in the skeletal system.
The doctor will ask you about your symptoms and examine your hand and wrist, and they might do more tests to determine how severe the carpal tunnel syndrome is. The doctor also may order an X-ray, ultrasound or MRI of the wrist to determine other causes of the pain.
The sooner you see a doctor for treatment, the less likely you are to have permanent damage from carpal tunnel syndrome. If you haven’t been using a brace, your doctor may recommend you do. Sometimes, steroid injections in the carpal tunnel can relieve symptoms.
For most people, carpal tunnel syndrome will worsen over time without treatments to stop or slow the progression.
“If left untreated, you could have permanent loss of feeling in those affected digits,” Dr. Miles says, “as well as loss of the muscle in the palm at the base of the thumb.”
Surgery for Carpal Tunnel Syndrome
If nonsurgical treatments don’t stop the symptoms or if the thumb muscles start weakening, surgery may be necessary. A surgeon will cut the ligament that forms the roof of the carpal tunnel to relieve pressure on the nerve.
“Other structures in the wrist will hold the tendons and nerve in place once the ligament has been cut,” Dr. Miles says, so you should not lose any function in your hand after surgery.
You may be able to perform light activities within a few days or a week of the surgery, and you can get back to regular activities within one to three months.
Talk to your doctor if you are experiencing pain, numbness, burning or tingling in your hand. If you need a doctor, find one near you.