Carpal tunnel syndrome is a term commonly used when someone has numbness and tingling in the hand. Two nerves innervate the palm of the hand and pass through two separate tunnels. The median nerve passes through the carpal tunnel and the ulnar nerve passes through the tunnel of Guyon. Entrapment of the median nerve in the carpal tunnel results in numbness and tingling in the following distribution and is true carpal tunnel syndrome.

Entrapment of the ulnar nerve in the tunnel of Guyon results in the following distribution:

When someone experiences numbness and tingling into the entire hand there may be multiple nerve entrapments or entrapment of the entire nerve and vascular bundle in the area of the arm referred to as thoracic outlet syndrome.

Nerves are not meant to stretch, but glide with normal movements. The first step in treatment is a correct diagnosis.

When an issue progresses over time, usually there is more than one dysfunction leading to the symptoms. There are multiple sites throughout the neck, arm, and hand that nerves of the upper extremity can become entrapped causing numbness and tingling into the hand.