Trigger finger

Also called Stenosing tenosynovitis, Trigger thumb

A finger that catches, clicks or locks bent. A steroid injection cures most of them, and it is often not offered.

What it is

A tendon in the finger becoming thickened or its sheath narrowed, so the tendon catches as it moves, causing clicking, locking and pain.

The finger typically locks in a bent position and then releases with a snap, sometimes needing the other hand to straighten it. It is often worst first thing in the morning.

It is common, affects the ring finger and thumb most often, and is substantially more common in people with diabetes, where it is often multiple and more resistant to treatment. It also occurs with rheumatoid arthritis, hypothyroidism and after repetitive gripping.

**A corticosteroid injection cures around 70 to 90 per cent of cases**, often with one injection, and it is straightforward. It is under-offered, and people are frequently left with a locking finger for months, or sent straight to surgery.

Surgery, releasing the pulley, has a very high success rate and is used when injections fail or in diabetes where injections work less well.

Trigger thumb in a young child is a different, common and usually painless condition, where the thumb is held bent, and it often resolves without treatment.

Signs you might notice

Clicking or catching when bending or straightening a finger.

The finger locking in a bent position, releasing suddenly.

Pain or a tender nodule at the base of the finger, on the palm side.

Stiffness, worst in the morning.

Sometimes the finger locked bent and unable to straighten at all.

See a GP for: locking, pain interfering with use, or a finger stuck bent.

Urgent: a finger that is red, hot and swollen with fever, which may be infection; or a finger stuck bent after an injury, which may be a tendon injury rather than triggering.

In a child, a thumb held bent since infancy is usually congenital trigger thumb and should be assessed but is rarely urgent.

How it can affect day-to-day life

It affects grip and daily tasks in ways that sound minor and are not: buttons, keys, jars, tools, and holding a steering wheel.

Morning stiffness and locking is the classic pattern, and it eases through the day, which sometimes leads to it being dismissed at an afternoon appointment.

For people with diabetes, multiple digits are often affected, injections work less reliably, and surgery is more likely to be needed. Knowing that in advance avoids a sense of failure.

Splinting the finger straight at night is a reasonable first step and helps a proportion of people, particularly early on.

Avoiding repeated forceful gripping helps, though for many manual jobs that is not practical, and that is worth saying rather than issuing unusable advice.

After surgery, movement should start early to avoid stiffness, and hand therapy is helpful.

Supporting someone well

Ask about a steroid injection. It is the treatment that works and it is frequently not offered.

Try a night splint holding the finger straight, particularly in early or mild cases.

Reduce repeated forceful gripping where that is possible; adapt tools and handles.

Use simple pain relief and a gentle range-of-movement routine.

Ask about surgery if injections have not worked, or from the start in diabetes with multiple fingers.

Get blood glucose and thyroid function checked if not already known; both are associated.

Start moving early after surgery and ask for hand therapy.

Get a red, hot, swollen finger with fever seen urgently.

Where to get help

A GP practice for assessment and injection; many practices and musculoskeletal services do these.

Hand surgery for release where injections fail.

Hand therapy after surgery.

Arthritis UK and the Chartered Society of Physiotherapy for hand exercises.