Trigger Finger

(Digital Flexor Tendinitis; Digital Flexor Tenosynovitis; Stenosing Flexor Tenosynovitis)

ByDavid R. Steinberg, MD, Perelman School of Medicine at the University of Pennsylvania
Reviewed/Revised May 2024
VIEW PROFESSIONAL VERSION

Trigger finger is locking of a finger in a bent position caused by inflammation of a tendon in the finger.

(See also Overview of Hand Disorders.)

The cause of trigger finger is unknown. Trigger finger is common among people with rheumatoid arthritis or diabetes. Repetitive use of the hands (as may occur from using heavy gardening shears) makes trigger finger more likely to develop.

In trigger finger, a finger becomes locked in a bent position. The finger locks when one of the tendons that flex the finger becomes inflamed and swollen, often with a noticeable round, raised area (nodule) in the palm that may be tender to touch. The inflammation and swelling may cause pain in the palm and in the base of the finger, especially when the finger is flexed and extended.

Normally, the tendon moves smoothly in and out of its surrounding sheath as the finger straightens and bends. In trigger finger, the inflamed tendon can move out of the sheath as the finger bends. However, when the tendon is very swollen, it cannot easily move back in as the finger tries to straighten, and therefore the finger locks. To straighten the finger, a person must pull on the finger to force the swollen area into the sheath—causing a sudden release and popping sensation similar to that felt when pulling a trigger.

A doctor makes the diagnosis of trigger finger by examining the hand and finger.

Trigger Finger Position

In trigger finger, a finger becomes locked in a bent position when one of the tendons that flex the finger becomes inflamed and swollen.

Treatment of Trigger Finger

  • Measures to relieve pain

  • Sometimes a corticosteroid injection

  • Sometimes surgery

In people with trigger finger, splinting, moist heat, and nonsteroidal anti-inflammatory drugs (NSAIDs) can help people who have swelling and pain.

Sometimes a corticosteroid and a local anesthetic are injected into the tendon sheath and, along with splinting, may provide safe and temporary but rapid relief of pain and triggering.

Surgery is commonly needed to treat chronic trigger finger.

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