Carpal Tunnel Syndrome

The carpal tunnel is a passageway in the wrist formed by the eight carpal (wrist) bones, which make up the floor and sides of the tunnel, and the transverse carpal ligament, a strong ligament stretching across the roof of the tunnel.

Inside the carpal tunnel are tendons which run down from the muscles in the forearm and work to flex your fingers and thumb. Also running through the tunnel is the median nerve, a cord about the size of a pencil, supplying information back to the brain about sensations you feel in your thumb, index, middle and (occasionally) ring fingers.

In carpal tunnel syndrome the median nerve is squeezed, often because the tendons become swollen and overfill the tunnel. Symptoms, such as numbness, burning or tingling, affect the thumb, index finger, fore finger and inside of the fourth finger, as well as the same region of the hand.

The outside edge of the hand, the little finger and the outside of the fourth finger are not affected.