There are eight small bones in the wrist called as carpal bones. A ligament called as retinaculum covers across the front of the wrist. There is a space between the bones of the wrist (carpal bones) and the ligament (retinaculum). This space is called as carpal tunnel. Median nerve is the main nerve supplying the hand. Median nerve passes through the carpal tunnel and then divides into smaller branches in the palm. Median nerve supplies the thumb, index finger, middle finger and part of the ring finger. Also, small muscles at the base of the thumb are supplied by the median nerve. The tendons of the flexor muscles of the forearm that connects to the fingers, also pass through this tunnel.
Carpal tunnel syndrome is relatively common condition and is a set of symptoms consisting of pain, numbness, burning or tingling sensation in the hand or fingers caused by the entrapment of the median nerve in the carpal tunnel.
About 1 in 1000 people are affected by this and the susceptible group comprise of writers, regular gardeners, tennis players, computer programmers, or anyone spending hours working on the keyboard and mouse. It is also common in pregnancy. Chronic cases often need surgery.