You crawl into bed and curl up like a contented baby, and if you’re like a lot of other people, you tuck your hands up under your chin. One night, you wake up to find one of your hands numb and tingly. You shake it out and the feeling goes away. It happens more than once and you begin to notice a similar sensation during the day, perhaps when you are holding the phone or reading a book or driving.
At first, the symptoms come and go, but slowly, over time, they become more constant and you start to feel clumsy. You drop things or fumble when you try to do something simple, like button your shirt. When a sharp piercing pain shoots through your wrist and up your arm you finally pay attention and decide that something is wrong.
What is the carpal tunnel and what can go wrong?
Taken all together, the symptoms suggest carpal tunnel syndrome. The carpal tunnel is a narrow tunnel in the wrist. The bones in the wrist form the bottom and sides of the tunnel. A strong band of connective tissue, known as the transverse carpal ligament, forms the top or palm side of the tunnel.
The median nerve, which starts at the shoulder and travels down the forearm into the wrist and hand, passes through the carpal tunnel. The nerve controls feeling in the palm side of the thumb and all but the little finger. It also controls muscles around the base of the thumb. Sharing space with the nerve inside the narrow tunnel are tendons, which the thumb and fingers need in order to bend. Synovial tissue surrounds and lubricates the tendons so that everything glides smoothly.
If the tissue becomes inflamed or swollen it can cause carpal tunnel syndrome. The carpal tunnel is already narrow and with swelling, it can narrow even more and pinch the median nerve. A number of things can cause swelling. In most cases, it’s a combination of factors.
- Heredity — a narrower than usual carpal tunnel can run in families
- Extended overuse of the hand
- Hormonal changes related to pregnancy or menopause
- Age. Carpal tunnel syndrome is more frequent in older people
- Medical conditions, e.g., diabetes, rheumatoid arthritis, underactive thyroid
One misconception about carpal tunnel syndrome is that it only affects people who either work on a computer or an assembly line all day long. Anyone can develop symptoms, although it’s unusual in people under age 20 and more common in women.
Common symptoms of carpal tunnel syndrome
While other conditions can cause hand pain, carpal tunnel syndrome has a characteristic set of symptoms, which usually begin gradually and are not connected to any specific injury or incident. Common symptoms include:
- Numbness, tingling and/or pain in the hand, especially the thumb, index and middle fingers
- Feeling like an electric shock through the hand
- Pain or strange sensations in the hand that travel to or from the shoulder
- Fullness and swelling
- Coolness in the fingertips; itchiness; hypersensitivity to touch
Diagnosis and treatment
In addition to listening to your history and examining your hand for tenderness, swelling and loss of sensation, your doctor may order diagnostic tests, including a nerve conduction test. Small electric shocks are applied to electrodes that are placed on the hand and wrist.
In the early stages, when symptoms are mild, wearing a splint or a brace to keep the wrist in a neutral position may be all that’s necessary to alleviate symptoms.
After about three months of bracing, if there is still a problem, a cortisone shot is often the next step. Cortisone reduces inflammation but, unfortunately, only temporarily.
If symptoms don’t go away with conservative measures or they get worse, surgery may be the best treatment option. The decision is usually based on the severity of symptoms. The goal of surgery is to relieve the pressure on the median nerve by opening a little window in the band of connective tissue that forms the top of the carpal tunnel. A small incision is made in the palm of the hand and the band is cut in two. Once the pressure is off, the nerve can start working again. Pain and tingling are usually relieved fairly quickly. Depending on how much damage there was to the nerve, it may take several months before all of the feeling returns to the hand.
Carpal tunnel surgery has a high success rate — over 90 percent. The key to a successful outcome is not waiting too long to do the surgery and doing it for the right reason. If damage is too severe, the nerve won’t be able to wake up, which is why people with symptoms of carpal tunnel syndrome shouldn’t wait until their hand is constantly numb before seeing a doctor.
Preventing carpal tunnel syndrome
Because carpal tunnel syndrome usually has more than one cause, preventing it can be a challenge. The following is a list of recommendations to lessen stress on your hands and wrists:
- Sleep with your wrists straight
- Try to avoid bending your wrists all the way up or down — keep them straight or in a relaxed middle position
- Take frequent breaks to rest or stretch your hands and wrist. This is especially important if you use equipment that requires a great deal of force or vibrates (think jackhammer).
- Keep your hands warm. Even wearing fingerless gloves that keep your hands and wrists protected, may be helpful.
Some people believe that carpal tunnel syndrome is a modern day malady and that computers, tablets, smart phones and other electronic devices are to blame. In fact, it was first recognized in the mid 1800s and the first surgery to release an affected nerve was done in 1930. So far, there is no conclusive evidence as to specific causes.
There is plenty of evidence, however, that the sooner carpal tunnel syndrome is diagnosed and treated, the less likely the median nerve will be permanently damaged and the more likely you’ll be able to get on with your life without a numb and painful hand.