1. De Quervain's Is a Stenosing Tenosynovitis
Similar to trigger fingers, de Quervain's is a stenosing tenosynovitis. The tunnel around the tendons becomes tight, or stenosed. As a result, the tendons and tendon covering become inflamed. The pain will be right over the tendons on the thumb side of your wrist, over the radial styloid (most distal part of your radius bone). The disease is named after a Swiss surgeon, Fritz de Quervain, who originally described the condition in 1895.
2. The Tendons Go to the Thumb
The tendons involved are in the first dorsal compartment. There are six dorsal compartments near the wrist, which house all the tendons that help straighten (extend) the fingers and wrist. The one involved in de Quervain's contains the EPB (Extensor Pollicis Brevis) and APL (Abductor Pollicis Longus) tendons. These are responsible for moving the thumb away from the palm. Pretend like you're going to palm a basketball. The direction your thumb moves is controlled by the first dorsal compartment. You should be able to see and feel the tendons on the side of your wrist.
Your doctor may palpate, or feel, the area to see if you are tender over those tendons. He may also have you perform a Finkelstein test; you'll place your thumb in your palm, close the other fingers over the thumb, then bend the wrist towards the pinky side. This will tug on the first dorsal compartment. If this recreates your pain, you have a positive test and likely have de Quervain's.
3. Get a Thumb Spica Brace
You can imagine that movements that move or stress the thumb would worsen the condition. Things such as writing, pinching, twisting and grasping will cause pain. Also, doing things in awkward positions, such as mothers taking care of newborn children can cause de Quervain's to flare up. Besides avoiding those activities and taking anti-inflammatory medications, you may want to try a thumb spica splint. This goes over your wrist and over your thumb, to prevent thumb movement. Make sure it is a spica brace and not just a regular brace, because if it doesn't immobilize the thumb, it probably won't help. It holds the thumb out at an angle from the palm. Interestingly, the word "spica" comes from the Latin word for spike of wheat. It describes how the ears of wheat go out from the stalk at an angle.
4. Try an Injection
If a period of rest and splinting doesn't help, you may want to try a cortisone injection into the tendon sheaths to calm down the inflammation.
5. Surgery May Help If All Else Fails
If the injections fail, you may want to consider a release of the tendon sheaths. This is an outpatient procedure, done through a small incision on the side of the wrist. The tendons are found and the tendon sheath is incised to release the pressure and tightness on the tendons.
