Carpal Tunnel Syndrome (CTS), which is often RSI (repetitive stress injury), can be caused by many things. Sometimes it is just a dull ache in your wrists. Other times it can be pain spreading up your arm to your shoulders or down into your hand. It can have numbness or tingling pain. You can have trouble holding objects or handling the steering wheel of your car.
The best known cause for CTS is people spending hours a day sitting at their computer keyboards.