Carpal tunnel release is a surgery used to treat and potentially heal the painful condition known as carpal tunnel syndrome. Doctors used to think that carpal tunnel syndrome was caused by an overuse injury or a repetitive motion performed by the wrist or hand, often at work. They now know that it’s most likely a congenital predisposition (something that runs in families) – some people simply have smaller carpal tunnels than others. Carpal tunnel syndrome can also be caused by injury, such as a sprain or fracture, or repetitive use of a vibrating tool. It's also been linked to pregnancy, diabetes, thyroid disease, and rheumatoid arthritis.