We asked Randall Mohler, MD, an orthopaedic surgeon who specializes in hand care, to respond to patients' questions about carpal tunnel syndrome.

Answer: A malfunctioning nerve causes carpal tunnel syndrome. Nerves relay signals between the brain and body. In people with carpal tunnel syndrome, the signals have trouble passing through the relatively tight space of the carpal tunnel. The carpal tunnel is an area along the wrist.

Increased pressure on the nerve in the tight carpal tunnel is the primary problem, but some medical conditions make nerves more likely to be affected by increased pressure (diabetes and thyroid disease, for example). Older individuals are also more likely to have carpal tunnel syndrome. We usually can't pinpoint the specific reason someone has carpal tunnel syndrome.

Answer: Usually symptoms come and go. Symptoms might wake you up from sleep or they may occur with certain activities, like reading or driving. Symptoms will then go away when you move your hand or change what you are doing. The numbness and pain tend to become more frequent and last longer as the problem grows worse. In severe cases, symptoms can become constant.

Answer: Exercises can decrease symptoms for a lot of people. The goals are to get more blood flowing to the area and to move the nerve so that the part of the nerve that is in the tunnel slips out for a breather.

Try fully curling the fingers into a fist and bending the wrist toward the palm. Then straighten the fingers and stretch the wrist back the other way. Repeat those motions about ten times.

Remember that carpal tunnel syndrome almost always starts gradually, so it has usually been present for a while before you even notice any symptoms. Stretches and exercises have to be performed regularly to be effective. Try to make it part of your daily routine--perhaps each morning and before bedtime.

Answer: Carpal tunnel syndrome is aggravated more by inactivity than by activity. That's why symptoms are common while sleeping and simple stretching and moving can be helpful. So, there really aren't any specific activities you need to avoid.

Symptoms often occur when your hand is in one position for too long. If you have a job or hobby that keeps you in one position, make it part of your routine to take short breaks to stretch and move your hands and arms. Just a few minutes each hour can be enough to prevent problems.

If you're regularly in one position, try to make sure your wrist is relatively straight, because bending the wrist either way increases the pressure around your nerve. If you wake up at night due to symptoms, try a splint on the wrist to keep it straight while you sleep.

Answer: First, try adjusting your position, stretching, and wearing a splint while sleeping for a couple weeks. If your symptoms start to improve, you're on the right track and you can just continue those things until your symptoms are gone. It's time to see a doctor if you aren't making any progress or if your symptoms are getting worse.

Answer: Surgery is reserved as a last resort. Even if symptoms don't go away with simple treatments like exercise and splints, they can often be controlled or will stay about the same for years.

If you have a condition like diabetes that makes you more susceptible, see your doctor to make sure the diabetes is well controlled.

If you smoke, this is one more reason to consider quitting.

If you're pregnant, you shouldn't even consider surgery, because the problem will usually go away after your baby is born.

Your doctor might recommend an injection into the wrist. Injections usually improve the symptoms, but sometimes the effects wear off and the symptoms come back. Injections shouldn't be done repeatedly, because they can weaken the tendons in the area.

Answer: Fortunately, carpal tunnel syndrome usually doesn't come back after surgery. Surgery opens the tight carpal tunnel space and takes pressure off the nerve. After surgery, it may take a while for the nerve to "wake up" and the symptoms to go away. In more severe cases, the recovery after surgery is slower and symptoms may not go away completely. In rare instances, carpal tunnel syndrome may recur after a period of years. If this happens, it may require more surgery.