Carpal tunnel syndrome , a painful condition of the hands, affects millions of individuals around the world. Numbness, tingling, weakness, and pain are caused by compression and trapping of the median nerve. The median nerve passes from the forearm into the hand underneath a band of connective tissue (tough, fibrous material that connects the bones of the hand) that runs across the end of the forearm where the arm meets the hand. That triangular space, formed by bones and connective tissue, is called the carpal tunnel. The carpal tunnel contains not only the median nerve but also several tendons. Performing repeated tasks, such as with typing, computer work, or mechanical activity, puts individuals at risk of developing carpal tunnel syndrome. Weight gain, water retention, pregnancy, and overuse of the hands all can cause or worsen carpal tunnel syndrome.