DeQuervain’s Tenosynovitis

First dorsal compartment tendonitis, more commonly known as deQuervain’s tendonitis or tenosynovitis after the Swiss surgeon Fritz de Quervain, is a condition brought on by irritation or inflammation of the wrist tendons at the base of the thumb.The inflammation causes the compartment (a tunnel or a sheath) around the tendon to swell and enlarge, making thumb and wrist movement painful. Making a fist, grasping or holding objects—often infants—are common painful movements with deQuervain’s tendonitis.

The cause of deQuervain’s tendonitis is an irritation of the tendons at the base of the thumb, usually caused by taking up a new, repetitive activity. New mothers are especially prone to this type of tendonitis: caring for an infant often creates awkward hand positioning, and hormonal fluctuations associated with pregnancy and nursing further contribute to its occurrence. A wrist fracture can also predispose a patient to deQuervain’s tendonitis, because of increased stresses across the tendons.

Pain over the thumb-side of the wrist is the main symptom. The pain may appear either gradually or suddenly, and pain is located at the first dorsal compartment at the wrist. Pain may radiate down the thumb or up the forearm. Hand and thumb motion increases pain, especially with forceful grasping or twisting. Swelling over the base of the thumb may include a fluid-filled cyst in this region. There may be an occasional “catching” or “snapping” when moving the thumb. Because of the pain and swelling, motion such as pinching may be difficult. Irritation of the nerve lying on top of the tendon sheath may cause numbness on the back of the thumb and index finger.