De Quervain syndrome is a hand condition resulting from inflammation and constriction of tendons extending to the thumb.

It is associated with inflammation of two tendons (abductor pollicis longus and extensor pollicis brevis) on the outer side of the thumb and wrist. It often occurs due to repetitive or excessive thumb, hand, and wrist movements, overexertion, or trauma. Additionally, hormonal changes during pregnancy can lead to the development of this syndrome.

Symptoms include pain during thumb movements, occasional swelling, and limited mobility. Diagnosis is typically made through a physical examination and symptom assessment.

Treatment options include rest, cold application, wrist splint, medication, and corticosteroid injections in the affected area. The use of a splint is highly effective, providing support, reducing stress on tendons and soft tissues, promoting rest, and aiding in tendon healing.