What causes de Quervain's tenosynovitis?

Two tendons that move the thumb travel along the wrist's thumb side. Repeated lifting, wringing, typing, gaming, or forceful pinching can make the tendon covering swell and restrict smooth movement. Caring for a baby can involve frequent wrist deviation and lifting, which is why the condition is sometimes called mummy thumb. Hormonal and fluid changes around pregnancy may also contribute, but symptoms can occur in anyone. Pain may spread toward the forearm and worsen when the thumb is used.

Rest the painful movements without completely immobilising the hand for long periods. Keep the wrist straighter when lifting, use both hands for heavier objects, and avoid repeated thumb pinching. Cold packs wrapped in cloth may settle discomfort. A healthcare professional can recommend a thumb-and-wrist support, gentle exercises, or medicines after checking your health history. Return to demanding hand tasks gradually as movement becomes easier.

Book an assessment when pain persists despite reducing the provoking activity, limits thumb movement, or affects sleep and childcare. Seek prompt help after a fall, sudden loss of thumb strength, marked swelling, redness, fever, or a thumb that looks out of position. Numbness or colour change in the hand also deserves timely evaluation.

Ask which tendon movements reproduce the pain, whether a splint is suitable for your routine, and how to lift or work while the wrist settles. Discuss medication safety if you are pregnant, breastfeeding, or managing another condition.