De Quervain’s tenosynovitis is a condition where there is swelling and inflammation of the tendon sheaths in the wrist. It primarily affects two tendons:
- Abductor pollicis longus (APL) tendon
- Extensor pollicis brevis (EPB) tendon
It is a type of repetitive strain injury and results in pain on the radial side of the wrist.
One notable cause of bilateral De Quervain’s tenosynovitis is in new parents repetitively lifting newborn babies in a way that stresses the tendons of the thumb. For this reason, it is sometimes referred to as “mummy thumb”.
Basic Anatomy and Pathophysiology
The abductor pollicis longus acts to abduct the thumb and abduct the wrist. The tendon inserts into the base of the first metacarpal bone (at the base of the thumb).
The extensor pollicis brevis also acts to abduct the thumb and abduct the wrist. The tendon inserts into the base of the proximal phalanx of the thumb.
Tendon sheaths can surround tendons. A tendon sheath is formed by connective tissue (synovial membrane) that covers the tendons and is filled with synovial fluid. They help lubricate and protect the movement of the tendons within them.
The extensor retinaculum is a fibrous band that wraps across the back (dorsal side) of the wrist. The APL and EPB pass underneath the extensor retinaculum. Repetitive movement of the APL and EPB under the extensor retinaculum result in inflammation and swelling of the tendon sheaths.
Presentation
Patients present with symptoms at the radial aspect of the wrist near the base of the thumb. Typical symptoms include:
- Pain, often radiating to the forearm
- Aching
- Burning
- Weakness
- Numbness
- Tenderness
There is a special test for De Quervain’s tenosynovitis called Finkelstein’s test. There is some confusion about what this is, depending on where you look. Most sources describe the first manoeuvre below as Finkelstein’s test, but it may be Eichhoff’s test.
Finkelstein’s test (or maybe Eichhoff’s test) involves the patient making a fist with their thumb inside their fingers. Then, the wrist is adducted (ulnar deviation), causing strain on the APL and EPB tendons. If this movement causes pain at the radial aspect of the wrist, the test is positive, indicating De Quervain’s tenosynovitis.
The original Finkelstein’s test involves the patient resting their forearm on a surface in a neutral position with the wrist hanging off and unsupported. The examiner holds the patient’s thumb and passively flexes the thumb into the palm, causing the wrist to adduct (ulnar deviation), putting strain on the APL and EPB tendons. If this causes pain at the radial aspect of the wrist, the test is positive, indicating De Quervain’s tenosynovitis.
Management
Management can involve:
- Rest and adapting activities
- Using splints to restrict movements
- Analgesia (e.g., NSAIDs)
- Physiotherapy
- Steroid injections
Rarely, surgery may be required to release (cut) the extensor retinaculum, releasing the pressure and creating more space for the tendons.
Last updated August 2021
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