Get a grip on De Quervain’s tenosynovitis, aka ‘Mommy thumb’

Get a grip on De Quervain's tenosynovitis, aka 'Mommy thumb'

Many people have heard of carpal tunnel syndrome, a painful condition of the wrist. But there is another troublesome hand condition that can cause just as much pain: De Quervain's tenosynovitis, sometimes called "Mommy thumb."

The condition involves two tendons connecting the thumb to muscles in the forearm, and the tendon sheath or "tunnel" at the base of the thumb surrounding these tendons. If the tendons swell, or the sheath becomes thicker, the sheath can become too tight for the tendons, causing friction and pain in the thumb side of the wrist when moving the thumb or grasping an object, according to the American Academy of Orthopaedic Surgeons

Who Gets De Quervain's?

The condition can strike at any age, but is more common in people in their 50s and 60s, said Cape Cod Healthcare plastic surgeon Julian D'Achille, MD, MPH. Women are six times more likely to develop it than men, he added. It's also called "Mommy thumb" because mothers may fall victim to it from picking up their infants, grasping them with thumbs pointing up. It's believed to be caused by repetitive motion, but swelling due to pregnancy may be a factor, as well as age and arthritis, he said.

"I've seen a lot in people (with the condition) who work in liquor stores, lifting bottles. Musicians (gripping the neck or guitar or other instrument), and a lot of landscapers and gardeners," said Dr. D'Achille, who is chief of surgery at Falmouth Hospital. He estimated the condition affects 1-3 percent of the population.

Anatomical differences in the structures of the first of six compartments of the wrist (the area containing the two thumb tendons and sheath) affect how they glide or rub against each other, likely predisposing some people to develop De Quervain's tenosynovitis, and also may influence the effectiveness of various therapies, according to an April 24, 2024 article in Cureus.

Diagnosis and Treatment

"Most of the time, we don't need imaging" to diagnosis De Quervain's, Dr. D'Achille said. "Arthritis at the base of the thumb can mimic De Quervain's, so sometimes we obtain an X-ray if the diagnosis is unclear."

Usually, diagnosis is done by a simple test called the Finklestein procedure, he said. A patient makes a fist with the fingers wrapped around the thumb, then bends the fist down toward the little finger. If this causes pain, De Quervain's typically is the culprit.

Dr. D'Achille described the following treatment options:

1. Taking ibuprofen or other NSAIDs "for a longer course than usual" to reduce pain and inflammation.
2. Immobilize the thumb with a spica brace: "This tends not to work very well. The failure rate is probably around 70 percent, (because) people take the brace off," he said. Dr. D'Achille describes appropriate braces to patients so they can buy them online, as these items are not commonly stocked in drug stores. Some patients show up with wrist braces designed to alleviate carpal tunnel syndrome, but these won't help De Quervain's tenosynovitis, he said.
3. Hand therapy
4. Steroid injections: It is about 75 percent effective, and is temporary, lasting on average about three months. It reduces inflammation and thins out tissue a little. Possible downsides include bruising and swelling and a possible loss of pigmentation in the skin around the injection site.
5. Surgery: "If you're getting to your third injection, it's probably time to think about surgery," he said. Done under either local anesthesia or sedation, a 1.5-2 cm (less than an inch) cut is made on the thumb side of the wrist. The tendon sheath is then cut down its center to release pressure on the tendons, which usually are both contained in one sub-compartment. However, 24-37 percent of people have two sub-compartments, one for each tendon, so surgeons must ensure both can move freely. Recovery takes two to four weeks, with sutures removed after two weeks. Patients are instructed to not lift anything heavier than 10 lbs. for two weeks. "If someone seems like they're really struggling, we send to hand therapy program," Dr. D'Achille said, but that's not typical. Risks include injury to nerves that could result in a numb area, or cause a neuroma - a scar of nerve tissue that can be very painful. More common is temporary numbness caused by moving nerves out of the way during surgery.

According to the American Academy of Orthopaedic Surgeons, 80 percent of people with De Quervain's can find relief without surgery, and the 20 percent who need surgery generally do well. The academy said while surgical complications are rare, people with diabetes may find less success with steroid injections and be more at risk for having complications from surgery, such as difficulty with healing or infection.