The primary symptom of de Quervains is pain at the base of the thumb near the wrist. The pain can be sudden and sharp or increase on a gradual basis with use of the thumb or hand. de Quervains is almost always associated with tenderness and swelling of the styloid process of radius bone. Pain can radiate into the forearm and thumb.
de Quervains tenosynovitis is the thickening and inflammation of the sheath containing the tendons of the inner wrist and thumb area (extensor pollicis brevis and abductor pollicis longus tendons). de Quervain's Tendonitis results from inflammation or constriction of the tendons of the muscles of the thumb at the point where they pass into the wrist. In many cases both tenosynovitis and tendonitis occur, a condition known as tendinopathy.