Carpal tunnel syndrome is caused by compression of the median nerve in the carpal tunnel of the wrist. It affects up to 10% of the general population and is characterized by motor, sensory, vasomotor and trophic symptoms in the hand. Conservative treatments include splinting, anti-inflammatory medications, injections, and vitamin B6, while surgical treatment involves releasing the transverse carpal ligament to decompress the median nerve. Diagnosis is based on symptoms, physical exam findings like a positive Phalen's or Tinel's sign, and electrodiagnostic testing to measure nerve conduction velocities.