The Volume Effect of Hydrodissection for Carpal Tunnel Syndrome

Inclusion Criteria: * Age 20-80 * Electrophysiological diagnosis of carpal tunnel syndrome * At least one of the following two: 1. Tenderness or numbness over median nerve innervated dermatome over 2 months 2. Phalen test or Tinel sign or flick sign positive Exclusion Criteria: * History of wrist surgery * Wrist trauma in recent two years * Received wrist injection in recent three months * History of brachial plexopathy, cervical radiculopathy or thoracic outlet syndrome * History of DM, thyroid disorder or autoimmune disease * Unable to cooperate with interview, examination or injection