Carpal tunnel syndrome (CTS) is a medical condition due to compression of the median nerve as it travels through the wrist at the carpal tunnel.[1] The main symptoms are pain, numbness, and tingling, in the thumb, index finger, middle finger, and the thumb side of the ring fingers.[1] Symptoms typically start gradually and during the night.[2] Pain may extend up the arm.[2] Weak grip strength may occur and after a long period of time the muscles at the base of the thumb may waste away.[2] In more than half of cases both sides are affected.[1]
Risk factors include obesity, repetitive wrist work, pregnancy, and rheumatoid arthritis.[3][4] There is tentative evidence that hypothyroidism increases the risk.[5] It is unclear if diabetes plays a role. The use of birth control pills does not affect the risk. Types of work that are associated include computer work, work with vibrating tools, and work that requires a strong grip.[3] Diagnosis is suspected based on signs, symptoms, and specific physical tests and may be confirmed with electrodiagnostic tests.[2] If muscle wasting at the base of the thumb is present, the diagnosis is likely.[3]
Being physically active can decrease the risk of developing CTS. Symptoms can be improved by wearing a wrist splint or with corticosteroid injections. Taking NSAIDs or gabapentin does not appear to be useful. Surgery to cut the transverse carpal ligament is effective with better results at a year compared to non surgical options. Further splinting after surgery is not needed. Evidence does not support magnet therapy.[3]
About 5% of people in the United States have carpal tunnel syndrome.[6] It usually begins in adulthood and women are more commonly affected than men.[2] Up to 33% of people may improve without specific treatment over approximately a year.[1] Carpal tunnel syndrome was first fully described after World War II.[7]
