Carpal tunnel syndrome is caused by a pinched nerve in the wrist. (1)
The carpal tunnel is a narrow passageway on the palm side of the wrist. One of the main nerves in the hand — the median nerve — passes through this space in the wrist on its way to the hand.
The median nerve runs from the neck down through the arm to the hand. It controls the muscles at the base of the thumb. It also carries signals about sensation from the thumb, index, long, and ring fingers to the brain.
Carpal tunnel syndrome happens when the carpal tunnel becomes narrowed or when the tissues around the tendons passing through the carpal tunnel become swollen, putting pressure on the median nerve.
This abnormal pressure can pinch the median nerve, causing pain, weakness, numbness or tingling in the hand and fingers. Sometimes carpal tunnel syndrome can cause pain or numbness in the lower part of the arm as well. These symptoms usually start gradually and worsen over time.
It’s not clear whether carpal tunnel syndrome can be prevented. And if left untreated, carpal tunnel syndrome can lead to serious, permanent damage to the nerves of the hand, fingers, and thumb. The good news is that carpal tunnel syndrome is usually very treatable. (2)
Carpal tunnel syndrome is a common nerve condition. It affects between 4 and 10 million Americans. (3) According to the physician-run website UpToDate, that’s about 1 to 5 percent of the U.S. population. (4)
Carpal tunnel syndrome typically appears in middle-aged and older adults. It occurs less often in younger people.
Women are about 3 times as likely as men to develop carpal tunnel syndrome. That may be at least partly due to relatively smaller wrist bones in many women, creating a tighter space or tunnel for tendons and nerves to pass through. (5)
Hormonal changes — especially those that occur during menopause — may also play a role. The U.S. Department of Health and Human Services says women are most likely to experience carpal tunnel syndrome between the ages of 45 and 54. (5)
While there’s no known way to prevent the development of carpal tunnel syndrome, there is evidence that certain healthy eating styles may help quell the systemic inflammation that contributes to pain.
Sometimes the cause of carpal tunnel syndrome is obvious. For instance, a wrist sprain or break could narrow the carpal tunnel passage and pinch the median nerve. Or rheumatoid arthritis could cause painful inflammation in the wrist joint. (2)
Many times, there is no single cause, or it’s not clear how or why the median nerve got pinched.
Most cases of carpal tunnel are due to a combination of factors. (2)
There are a number of risk factors that may increase your chances of developing carpal tunnel syndrome.
Risk factors for carpal tunnel syndrome include:
Some activities can cause carpal tunnel syndrome symptoms to flare up, but these activities are not usually causes of the condition.
Carpal tunnel syndrome triggers may include: (7)
People used to think that carpal tunnel syndrome was caused by too much use of computer keyboards and other tech devices, including cellphones, PDAs, and video game controls.
That’s probably not true. A number of studies in recent years have failed to find a connection between computer keyboards, tech use, and carpal tunnel syndrome. (4)
Another myth is that you need surgery to fix carpal tunnel syndrome. Most people can get relief from carpal tunnel syndrome symptoms with nonsurgical treatments. (8)
Surgery for carpal tunnel syndrome can be very effective. But surgery typically is only considered in people whose pain doesn’t go away after trying other treatments such as splints and steroid injections. (8)