de Quervain tenosynovitis is a common cause of radial-sided wrist pain encountered in clinical practice. This painful condition is named for Swiss surgeon Fritz de Quervain who first described this constellation of symptoms and their cause in 1895. As a result of repetitive high torque twisting motions of the wrist and occasionally as a result of direct trauma to the tendons of the abductor pollicis longus and extensor pollicis brevis at the level of the radial styloid process, de Quervain tenosynovitis can cause significant pain and functional disability if not promptly treated. On rare occasions, de Quervain tenosynovitis can develop without antecedent trauma, especially in the parturient, and this setting is often referred to as mommy’s thumb or wrist. The symptoms of de Quervain tenosynovitis are the result of inflammation and edema of the tendons and tendon sheath of the abductor pollicis longus and extensor pollicis brevis muscles at the level of the radial styloid process (Fig. 73.1). If untreated, a thickening of the tendons and tendon sheath may occur and cause a painful constrictive tenosynovitis (Fig. 73.2). In some patients, a triggering phenomenon of the thumb may occur as a result of the thickened tendon locking or catching in the constricted tendon sheath. Arthritis and gout of the first metacarpal joint also may coexist with and exacerbate the pain and disability of de Quervain tenosynovitis.

Activities associated with the development of de Quervain tenosynovitis include repetitive hand shaking, scooping ice cream, or using a screwdriver. The pain of de Quervain tenosynovitis is sharp and constant and is exacerbated by any activities requiring active pinching of the thumb or ulnar deviation of the wrist. The pain is localized to the area over the radial styloid process and is associated with increasing functional disability if the inflammatory process remains untreated.

On physical examination, there is tenderness and swelling over the tendons and tendon sheaths along the distal radius, with point tenderness over the radial styloid. A creaking tendon sign may be noted with flexion and extension of the thumb, and triggering of the thumb may occur. Patients with de Quervain tenosynovitis demonstrate a positive Finkelstein test (Fig. 73.3). The Finkelstein test is performed by stabilizing the patient’s forearm, having the patient fully flex his or her thumb into the palm, and then actively forcing the wrist toward the ulna. Sudden severe pain is highly suggestive of de Quervain tenosynovitis.

Plain radiographs of the wrist are indicated in all patients suspected of suffering from de Quervain tenosynovitis to rule out occult bony pathology and to identify calcific tendonitis. Based on the patient’s clinical presentation, additional testing may be indicated, including complete blood cell count, uric acid, sedimentation rate, and antinuclear antibody testing. Magnetic resonance imaging and ultrasound imaging of the
wrist are indicated to assess the status of the abductor pollicis longus and extensor pollicis brevis tendons and tendon sheath as well as to identify other occult pathology including arthritis and gout involving the first metacarpal joint (Fig. 73.4).

The key landmarks when performing ultrasound-guided injection for de Quervain tenosynovitis are the radial styloid process and the abductor pollicis longus and extensor pollicis brevis tendons and tendon sheath (Fig. 73.5). The function of the abductor pollicis longus and extensor pollicis brevis muscles is radial abduction of the thumb. The radial artery and the superficial branch of the radial nerve are in proximity to the injection site for de Quervain tenosynovitis and may be traumatized if the needle is placed too medially.

The benefits, risks, and alternative treatments are explained to the patient, and informed consent is obtained. The patient is then placed in the sitting position with the elbow flexed to about 100 degrees and the forearm resting comfortably with the hand in neutral position and the little finger against a padded bedside table (Fig. 73.6). With the patient in the above position, the radial styloid process and the abductor pollicis longus and extensor pollicis brevis tendons at that

level are identified by palpation. Identification of the tendons is facilitated by having the patient radial deviate the wrist against examiner resistance (Fig. 73.7). At the level of the radial styloid, a high-frequency linear ultrasound transducer is placed in a transverse position over the abductor pollicis longus and extensor pollicis brevis tendons, and an ultrasound survey scan is taken (Figs. 73.8 and 73.9). Color Doppler may aid in identification of the radial artery and help separate it with the superficial radial nerve, which lies just radial to the radial artery (Fig. 73.10). The tendons will appear as
the hyperechoic “hole” in the hypoechoic tendon sheath. In most patients, the tendons will be seen to pass through a single sheath (see Fig. 73.4). However, in a small number of patients, the tendon sheath will appear to travel through separate subcompartments divided by a subcompartmental septum (Fig. 73.11). An effusion surrounding the affected tendons can often be identified with ultrasound imaging (Fig. 73.12). When the tendon sheath is identified, the skin overlying the area beneath the ultrasound transducer is then prepped with antiseptic solution. A sterile syringe containing 1.0 mL of 0.25% preservative-free bupivacaine and 40 mg of methylprednisolone is attached to a 1½-inch, 22-gauge needle using strict aseptic technique. The needle is placed through the skin just above the superior border of the transducer and is then advanced using an out-of-plane approach with the needle trajectory adjusted under real-time ultrasound guidance so that the needle tip ultimately rests within the tendon sheath but outside the substance of the tendons themselves (Figs. 73.13 and 73.14). When the tip of the needle is thought to be in satisfactory position, after careful aspiration, a small amount of local anesthetic and steroid is injected under real-time ultrasound guidance to confirm that
the needle tip is in the proper position. After proper needle tip placement is confirmed, the remainder of the contents of the syringe are slowly injected. There should be minimal resistance to injection. If subcompartments are identified within the tendon sheath, repositioning of the needle to inject both compartments may be required.