Carpal Tunnel Syndrome - Causes

The carpal tunnel is a narrow passageway. Any swelling in this area causes pressure on the median nerve. That pressure eventually makes it difficult for a person to use the hand normally. Some conditions that can lead to pressure on the median nerve include pregnancy, obesity (see obesity entry), arthritis (see arthritis entry), diabetes (see diabetes mellitus entry), certain diseases of the thyroid and pituitary glands, and injuries to the arm and wrist.

One of the most common causes of CTS is repetitive motion. Repetitive motion is any activity that a person performs over and over again. Typing, working at a computer keyboard or cash register, playing some kinds of musical instruments, and working at certain types of factory jobs may involve repetitive motion. Repetitive motion forces a person to use the wrist over and over again and can lead to swelling in the carpal tunnel area, subsequent pressure on the media nerve, and thus to CTS.