What is de Quervain's tenosynovitis, and why is it called mommy thumb?

In short

De Quervain's tenosynovitis is inflammation of the two thumb tendons where they pass through a tight tunnel on the thumb side of the wrist, causing pain when you lift or grip. It is nicknamed mommy thumb because lifting a baby provokes it, but it is not limited to mothers.

Written for patients by The Hand and Wrist Institute. Prepared for review by John T. Knight, MD. Last updated September 5, 2026How we write and review

Call (817) 382-6789 to have this looked at, or book online with Dr. Knight.

What de Quervain's tenosynovitis is

Let's take a look at the thumb side of your own wrist. Put your thumb out as if you were hitching a ride and two cords stand up at the base of the thumb, running from the forearm across the wrist. Those are the tendons that pull the thumb away from the palm, and they travel together through a narrow tunnel on that side of the wrist. Repetitive thumb movement, especially thumb movement combined with lifting, sets up friction in that tunnel, the lining swells, the space gets tighter, and every pull of the thumb hurts. That is de Quervain's tenosynovitis, or what most people meet under the name mommy thumb.¹

The pain sits on the thumb side of the wrist, it is worst when you lift with the thumb out, and it often travels up the forearm. Turning a door handle, lifting a full kettle and picking a child up under the arms are the movements that find it.

Is it mommy thumb or carpal tunnel, and does it only affect mothers?

Two things get confused here. The first is the name. It came from how often this turns up in the months after a birth, when a baby is lifted dozens of times a day with the thumbs spread wide. It describes a pattern of use, not who is allowed to get it. Anyone whose thumb works hard against resistance can develop it, and the practice keeps a page on exactly that question for fathers, grandparents, tradespeople and heavy phone users.

The second is the condition it gets mistaken for. Carpal tunnel syndrome is a nerve squeezed inside the wrist, and it announces itself with numbness and tingling in the fingers, often waking you at night.² De Quervain's is a tendon problem, and it shows up as sharp pain on the thumb side of the wrist when you lift or grip, without numbness. So here is the test you can apply: pins and needles in the fingers means think nerve, pain at the base of the thumb that spikes when you lift means think tendon. You can have both, which is why the exam settles it and this page does not.

What to do first, in order

The ladder starts with rest, which is the part that is hard to arrange when you carry a baby all day.

1. Immobilise the thumb and wrist in a brace so the inflamed tendons are no longer pulled.
2. Add an anti-inflammatory such as ibuprofen, and ice the sore spot.
3. Change the lift. Dr. Knight's advice is to keep the thumb tucked in and scoop the baby up under the bottom and torso rather than gripping under the arms with the thumbs spread.
4. A cortisone injection into the tendon sheath if rest, bracing and medication have not settled it.
5. Surgery last, and only if conservative treatment fails. It opens that tight tunnel through a small incision on the thumb side of the wrist, and Dr. Knight is emphatic that every compartment has to be found and released.

When to call us

• The pain at the base of the thumb no longer eases with rest and is there every time you lift.
• You have started avoiding lifting your child, or you fear dropping what you are holding.
• Weeks in a thumb brace with an anti-inflammatory have made no difference.
• The thumb side of the wrist is swollen, or there is a creaking you can feel when you move the thumb.
• The pain began after a fall onto the wrist, or numbness has joined it, which suggests more than a tendon is involved.