Michael W Bowman M.D. FACS
Dequervains Tenosynovitis is a constricted or “pinched tendon” in the thumb or radial side of the wrist. Two tendons, the Abductor Pollicis Longus (APL) and the Extensor Pollicis Brevis (EPB) run from the thumb to the radial or thumb side of the wrist in a small tunnel called the first dorsal compartment. See figure 1. These tendons straighten or extend the thumb and abduct the thumb (pull the thumb away from the other fingers). In a small percentage of patients the APL and EPB tendons are actually separated into two smaller compartments over top of the Radius. A broad sheet of fibrous tissue called the retinaculum runs over top of the two tendons at the wrist, holding them in place. The tendons are covered by a slick tissue called tenosynovium. There is limited clearance for the tendons in this tunnel over the radius and any condition that causes swelling or inflammation in the tunnel can produce irritation of the tenosynovium and Dequervains Tenosynovitis
Symptoms of Dequervains Tenosynovitis are sharp or burning pain along the thumb or radial side of the wrist, often extending both up the thumb and up the arm. There may be stiffness with motion of the thumb towards the other fingers (adduction) or away from the other fingers (abduction). There may be a creaking sensation or noise with thumb motion called crepitus. This has also been called the “wet leather sign”, since it resembles the sound of stretching wet leather. There may be swelling on the thumb or radial side of the wrist. The area over the tendon at the wrist may be tender to touch. If there is significant swelling,the radial nerve, which supplies sensation to the dorsum or top of the thumb may be irritated, producing numbness or tingling. All of the symptoms above may be aggravated by wearing a tight watch or bracelet.
There are many causes for Dequervains Tenosynovitis. Direct trauma, such as a blow to the radial side of the wrist may cause swelling and symptoms. Frequent wearing of a tight wristwatch or bracelet may also produce Dequervains. A fracture of the underlying radius, even if undisplaced, may also produce this condition. Repetitive overuse of the thumb, such as using clippers, scissors and staplers or repetitive pinching may also be a cause. Inflammatory disorders such as rheumatoid arthritis, lupus or gout may cause swelling of the tenosynovium and produce Dequervains Tenosynovitis.
Initial treatment is usually conservative. This consists of discontinuing aggravating activities or wearing tight jewelry. Ice and anti-inflammatories are also helpful. A small injection in the tunnel or first dorsal compartment with Xylocaine and cortisone is also very helpful in approximately 80% of the cases. Finally, surgery is performed when conservative treatment is no longer effective. Surgery consists of a Dequervains Release. As an outpatient and using local standby or twilight anesthesia, a small longitudinal incision is made over the tendons at the radius. The fibrous band or retinaculum is released, allowing the tendons to move freely without friction. The skin is closed and a small dressing is applied. The patient is instructed to move their fingers freely, but no heavy gripping or lifting for two weeks. The dressing and incision must remain dry for two weeks afterwards. At two weeks postoperatively, the sutures are removed and the patient may shower as well as massage the scar. They may begin progressive activity after that. Possible complications are anesthesia related problems, wound healing problems or infection, irritation of the small radial nerves or snapping of the tendons.