de Quervain's tenosynovitis

INTRODUCTION

De Quervain's tenosynovitis refers to tenosynovitis of the abductor pollicis longus and extensor pollicis brevis tendons. It is most often a cumulative movement disorder due to chronic overuse of the wrist and hand. Bilateral or unilateral tenosynovitis may also accompany pregnancy, direct trauma, and systemic diseases such as rheumatoid arthritis and calcium apatite deposition disease [1,2].

The tendons of the abductor pollicis longus and extensor pollicis brevis traverse a thick fibrous sheath at the radial styloid process [3-5]. Repetitive or unaccustomed use of the thumb that involves pinching with the thumb while moving the wrist in radial and ulnar directions (eg, gripping and grasping) leads to thickening of the fibrous tendon sheath. Thickening results in inflammation and stenosis as the tendon sheath passes over the distal radius. Left untreated, this friction-induced tenosynovitis can progress to fibrosis and loss of flexibility of the thumb in flexion (stenosing tenosynovitis).

PRESENTATION

Patients with de Quervain's tenosynovitis typically note pain at the radial side of the wrist during pinch grasping or thumb and wrist movement. Pain may radiate to the thumb or up to the volar aspect of the wrist. The patient may complain of difficulty gripping, and often rubs over the radial styloid when describing the condition.

DIAGNOSIS

The diagnosis of de Quervain's tenosynovitis is suggested by the characteristic history of wrist pain on the radial side and the following physical examination findings:

• Ask the patient to open and close the hand to assess the full and smooth movement of the thumb. Smooth, painless, and complete movement of the thumb virtually excludes de Quervain's tenosynovitis.
• Local tenderness is present over the distal portion of the radial styloid, adjacent to the abductor pollicis longus tendon (picture 1).
• Pain is aggravated by resisting thumb extension and abduction isometrically (abduction is moving the thumb perpendicular to the palm) (picture 2).
• Pain is aggravated by passively stretching the thumb tendons over the radial styloid in thumb flexion (the Finkelstein maneuver, (picture 3). This motion stretches the tendon and tendon sheath and in some cases is so painful that the patient responds by lifting the shoulder to prevent the examiner from stretching the tendons.
• Palpation of the tendons in the anatomic "snuff box" area may reveal swelling when compared to the uninvolved side.
• Tendon fibrosis is assessed by evaluating flexion and circumduction of the thumb and by assessing the distensibility of the tissues over the radial styloid. Normally the soft tissues of the radial styloid should readily distend with 2 to 3 mL of local anesthetic, forming a bubble 1 1/2 inches long.