Trigger finger

Trigger finger arises where a tendon that bends the finger passes through a tight tunnel, the tendon sheath, in the palm. At the entrance sits a band called the A1 pulley. If the tendon thickens or the pulley narrows, the tendon no longer glides freely and snags as the finger moves, producing the catching and locking.

In most people there is no single cause and it develops without obvious reason. Several factors are linked with it:

• Age over 40, and female sex, as it is more common in women
• Diabetes, which raises the risk and can make it more stubborn
• Repetitive or forceful gripping
• An association with other hand conditions, including carpal tunnel syndrome and De Quervain's tenosynovitis

Inflammatory arthritis and an underactive thyroid are occasionally relevant.

Trigger finger has a recognisable pattern. Features may include:

• Catching, clicking or locking of a finger or thumb as it moves
• A finger that becomes stuck in a bent position and then snaps straight
• Stiffness, particularly in the morning
• Tenderness or a small lump at the base of the affected finger

Trigger finger can usually be recognised from the history and a simple examination of the hand. Confirming the diagnosis helps guide the right treatment.

Ultrasound can show the tendon and its sheath and confirm the problem, as well as allowing any injection to be placed accurately. Dr Borukhson uses point-of-care ultrasound during the consultation, so the hand can often be assessed in the same visit. You can read more on the ultrasound clinic page.

Milder cases may settle with rest, activity modification and sometimes a splint. Where symptoms persist, an ultrasound-guided injection into the tendon sheath is frequently very effective, and ultrasound guidance allows it to be placed precisely. More persistent cases may need referral for consideration of a minor procedure. The plan is agreed with you.

Day to day, small adjustments often ease the strain on the tendon. It helps to take regular breaks from gripping tasks, to pad the handles of tools and pens so the load is spread, and to move the finger gently through its range rather than forcing it when it catches.

• Ease off the activities that clearly aggravate it for a spell, rather than stopping using the hand altogether
• Wear a splint as advised, often at night, to rest the finger straight
• Keep the hand moving gently through the day to limit stiffness
• If you have diabetes, steady blood sugar control may support recovery

These measures will not always settle things on their own, but they can reduce the irritation and make day to day use more comfortable while you arrange an assessment.

Trigger finger is rarely an emergency, but some situations warrant prompter attention. Arrange a review without long delay if:

• A finger becomes fixed in a bent position and you cannot straighten it, even with your other hand
• The catching or locking is worsening, painful, or interfering with everyday tasks
• A finger has been locked for some time and the joint is stiffening, as a long-stuck finger can be harder to free

Seek same-day medical care if a finger or the palm becomes hot, red, swollen and increasingly painful, particularly with a fever or after a cut or bite, as this suggests infection rather than triggering. New numbness, marked weakness or spreading pain also deserves prompt assessment to look for another cause.

Trigger finger usually responds well to treatment, particularly when addressed early. If you have a finger that catches, clicks or locks, a specialist review, with ultrasound where helpful, can confirm the cause and offer effective treatment.

How is trigger finger diagnosed?

Trigger finger can usually be recognised from your account of the catching or locking and a simple examination of the hand, sometimes with a tender lump felt at the base of the finger. Because a few other hand problems can feel similar, confirming the cause is worthwhile. Ultrasound can show the tendon and its sheath and pinpoint where it is sticking. Dr Borukhson uses point-of-care ultrasound during the consultation, so the hand can often be assessed in the same visit.

Can trigger finger get better on its own?

Milder cases can settle, particularly if caught early and if you rest the finger and ease off the movements that aggravate it. A splint that holds the finger straight, often worn at night, can help too. That said, symptoms sometimes persist or recur. If your finger is regularly catching or locking, or it becomes stuck in a bent position, it is sensible to have it assessed rather than wait indefinitely.

How well does a steroid injection work for trigger finger?

An injection of steroid into the tendon sheath is a common and frequently very effective treatment, often easing the catching and locking. Using ultrasound to guide the needle helps place it precisely. Some fingers settle fully, while others improve for a time or need a second injection. If symptoms keep returning despite injection, referral for a small procedure to release the sheath may be discussed. Any plan is agreed with you.

Is trigger finger the same as carpal tunnel syndrome?

No, although both affect the hand and can occur together. Trigger finger is a problem with a tendon catching as the finger bends, causing clicking or locking. Carpal tunnel syndrome involves a nerve being compressed at the wrist, which typically causes tingling, numbness or weakness in the thumb and nearby fingers rather than catching. Because the symptoms differ, an examination, with ultrasound where helpful, can tell them apart and guide the right treatment.

When should I see a specialist about a trigger finger?

It is worth seeking review if your finger frequently catches, clicks or locks, if it becomes stuck in a bent position, or if it is painful or stiff enough to affect daily tasks. Early assessment is helpful, as trigger finger usually responds well to treatment when addressed promptly. A specialist review, with ultrasound where useful, can confirm the cause and offer effective treatment including a guided injection where appropriate.