Trigger Finger
A finger that catches or locks when you bend it
Quick Facts
- Type: Hand tendon condition
- Cause: Narrowed, inflamed tendon sheath
- Common in: Adults, often the dominant hand
- Hallmark: Catching, snapping, or locking of a finger
Overview
Trigger finger, known medically as stenosing tenosynovitis, is a condition that makes one of your fingers or your thumb get stuck in a bent position and then snap straight, like pulling a trigger. It happens when the tendon that bends the finger can no longer glide smoothly through the tunnel of tissue (the tendon sheath) that holds it close to the bone.
When the sheath becomes inflamed and thickened, the space inside narrows. A small swelling or nodule may form on the tendon, which then catches as it tries to slide through the tightened tunnel. The condition can affect any finger but is most common in the thumb, ring, and middle fingers. It is not dangerous, but it can be painful and interfere with everyday tasks.
Symptoms
Symptoms often start mild and gradually worsen. They are usually most noticeable in the morning, when gripping firmly, or when straightening the finger.
- A clicking, catching, or snapping sensation when moving the finger
- Stiffness, especially first thing in the morning
- A tender lump or bump at the base of the finger in the palm
- Pain at the base of the affected finger or thumb
- The finger locking in a bent position and then suddenly popping straight
- In severe cases, the finger becoming stuck and unable to straighten
Causes
Trigger finger develops when repeated or sustained gripping and the resulting irritation cause the tendon sheath to swell. The tendon then no longer glides freely, leading to catching and locking.
The exact reason the sheath becomes inflamed in a given person is not always clear. It is linked to repeated forceful use of the hand, but it can also develop without any obvious trigger. Certain health conditions make the tissue more prone to inflammation and thickening, which raises the likelihood of trigger finger developing.
Risk Factors
- Repeated gripping activities, at work or in hobbies
- Diabetes
- Rheumatoid arthritis and other inflammatory conditions
- An underactive thyroid (hypothyroidism)
- Being female and middle-aged
- Having had carpal tunnel syndrome or hand surgery
Diagnosis
Trigger finger is usually diagnosed from the history and a hand examination, without the need for imaging or laboratory tests:
- Physical exam: The doctor watches the finger open and close to see the catching or locking and feels for a tender nodule in the palm.
- History: Questions about hand use, morning stiffness, and related conditions such as diabetes help confirm the diagnosis.
Imaging is rarely needed and is used mainly to rule out other causes when the picture is unclear.
Treatment
Treatment usually starts with simple measures and moves to procedures only if symptoms persist.
- Rest and activity change: Avoiding repetitive gripping and forceful hand use lets the inflammation settle.
- Splinting: Wearing a splint, often at night, keeps the finger straight and rests the tendon.
- Anti-inflammatory medicine and stretching: Help relieve pain and improve movement.
- Steroid injection: A corticosteroid injected into the tendon sheath reduces swelling and often resolves symptoms, sometimes for good.
- Surgery: A minor procedure to release the tight part of the sheath is highly effective for persistent or severe cases that lock.
Many people improve with rest, splinting, or one or two injections, and surgery is reserved for cases that do not respond.
Prevention
- Take breaks from repetitive gripping or use of vibrating tools
- Use padded or larger grips on tools and equipment
- Stretch the hands and fingers during long tasks
- Keep underlying conditions such as diabetes and arthritis well managed
- Address early stiffness or catching before it worsens
When to See a Doctor
See a doctor if a finger catches, locks, or is painful at the base, especially if it interferes with daily activities or does not improve with rest. Seek prompt care if a finger becomes stuck and you cannot straighten it, if the area is hot, red, and swollen, or if symptoms follow a hand infection, as these may need urgent treatment.
Frequently Asked Questions
Will trigger finger go away on its own?
A mild case can improve with rest, splinting, and avoiding repetitive gripping. More established cases often need a steroid injection, which frequently resolves the problem. Surgery is very effective for fingers that keep locking.
Is trigger finger related to diabetes?
Yes. People with diabetes are more likely to develop trigger finger, and it can affect more than one finger. Keeping blood sugar well managed is part of reducing the risk and supporting recovery.
Does a steroid injection cure trigger finger?
A corticosteroid injection into the tendon sheath relieves symptoms in many people, sometimes permanently. Some need a second injection, and if symptoms return or the finger keeps locking, a minor surgical release is the next step.
What happens if trigger finger is left untreated?
It may stay mild, or it can worsen so the finger locks more often or becomes stuck in a bent position. Over time a finger left locked can become stiff and harder to fully straighten, so early treatment is helpful.
References
- Mayo Clinic. Trigger finger.
- American Academy of Orthopaedic Surgeons (OrthoInfo). Trigger Finger.
- MedlinePlus, U.S. National Library of Medicine. Trigger finger.
- American Society for Surgery of the Hand. Trigger Finger.