A condition caused by the thickening of ligaments and tendon sheaths at the wrist, with consequent compression of the median nerve at the palm. Affected individuals report numbness, tingling, and pain in the hand; the discomfort often becomes worse at night or after use of the hand. A physical examination of the injured hand during the early stages of the syndrome often reveals no abnormality. With more severe nerve compression, the individual experiences sensory loss over some or all of the digits innervated by the median nerve (thumb, index finger, middle finger, and ring finger) and weakness of thumb movement.