Carpal Tunnel Syndrome is usually associated with a crushing or tightening of the Median nerve as it passes through the Carpal Tunnel (Carpal - being bones ). Normally associated with a thickening of the ligament that wraps around the wrist.
However, if you were to follow the nerve path, you will find that the nerve starts in the neck moves across the shoulder and down the arm, terminating in the hand. The nerve can be pinched at any point and refer pain anywhere along its path.
Please see:
Carpal Tunnel Syndrome Fact Sheet: National Institute of Neurological Disorders and Stroke (NINDS)