Endoscopic carpal tunnel release surgery is done with aid of an arthroscope through a less- than-one-inch incision in the wrist. The small incision results in less post-operative pain, and a faster recovery. The surgery releases pressure on the hand's major nerve, which runs through a passageway in the wrist called the carpal tunnel. Pressure may be caused by disease (such as rheumatoid arthritis), injury, fluid retention, overuse, or repetitive motion. The pressure causes tingling in the hand, numbness, aching, and can lead to impaired hand function (carpal tunnel syndrome).