Quick answer. Trigger finger (stenosing tenosynovitis) is a common hand condition where a finger or thumb catches, clicks or locks in a bent position, sometimes needing the other hand to straighten it. It happens when a flexor tendon or its sheath thickens and no longer glides smoothly under the A1 pulley at the base of the finger. There is often a tender nodule in the palm and stiffness, especially in the morning. It is linked to diabetes, repetitive gripping and inflammatory arthritis. Many cases improve with splinting and a steroid injection, though injections work less well in diabetics. If it keeps locking, a quick day-surgery release of the A1 pulley is highly effective.
Trigger finger, medically known as stenosing tenosynovitis, is one of the most common hand complaints seen by orthopaedic and hand surgeons in Singapore. It causes a finger or thumb to catch, click or lock as you bend and straighten it, and in more severe cases the finger gets stuck in a bent position and has to be eased straight with the other hand.
The condition occurs when a flexor tendon or its surrounding sheath becomes thickened and can no longer glide smoothly through a narrow band of tissue called the A1 pulley at the base of the finger. It is strongly associated with diabetes. The reassuring part is that treatment is well established and very effective, ranging from splinting and a steroid injection to a simple day-surgery release.
At a glance
| Option | Best suited for | Notes |
|---|---|---|
| Splinting & activity change | Early or mild cases | Resting the finger and avoiding repetitive gripping; can settle mild triggering |
| Steroid injection | Persistent triggering, single digit | Often effective; works less well in diabetics, longstanding cases and multiple fingers |
| Surgical A1 pulley release | Locking that recurs or fails injection | Quick day surgery, very high success rate (resolution of triggering in most patients) |
What trigger finger is
Flexor tendons run from the forearm to the fingers inside protective sheaths, passing through a series of pulleys that hold them close to the bone. In trigger finger, the tendon or sheath thickens (often with a small nodule) so it no longer slides smoothly under the first pulley, the A1 pulley, at the base of the finger or thumb. As you straighten the finger, the nodule catches and then suddenly releases, producing the characteristic snap or “trigger”.
Symptoms
- Catching, clicking or snapping when bending or straightening the finger or thumb.
- Locking in a bent position in more advanced cases, sometimes needing the other hand to straighten it.
- A tender lump (nodule) in the palm at the base of the affected finger.
- Stiffness, especially in the morning, which may ease with movement.
- The thumb, ring and middle fingers are commonly affected; more than one finger can be involved.
Causes and the diabetes link
Often no clear cause is found, but recognised contributors include:
- Diabetes: trigger finger is notably more common in people with diabetes, and tends to be more stubborn to treat.
- Repetitive or forceful gripping – prolonged use of tools such as scissors or screwdrivers, or repetitive grasping tasks.
- Inflammatory and metabolic conditions such as rheumatoid arthritis and gout.
- It is more common in middle-aged adults and in women.
Non-surgical treatment
- Activity modification and splinting: resting the finger, sometimes with a splint to limit bending, can help early or mild triggering.
- Steroid injection: a small amount of corticosteroid placed around the A1 pulley can relieve triggering in a high proportion of cases. However, the success rate is lower in people with diabetes, in longstanding disease (present more than several months) and when multiple fingers are involved. Diabetics should also expect a temporary rise in blood sugar for a couple of weeks after the injection.
Surgery: day-surgery A1 pulley release
If triggering recurs after injection, or the finger keeps locking, surgery is highly effective. Trigger finger release involves a small incision in the palm to divide the A1 pulley, freeing the tendon to glide normally. It is a common procedure done as day surgery (you go home the same day), usually under local anaesthesia, with most patients getting complete and lasting resolution of triggering. As a day-surgery procedure, costs may be partly offset by MediSave; check eligibility with your provider.
When to see a doctor
See a doctor if:
- The finger locks and is difficult or impossible to straighten, or you have to use the other hand to unlock it.
- Triggering has lasted more than a few weeks or is getting worse.
- There is significant pain, swelling or loss of hand function.
- You have diabetes and notice new finger catching, as earlier review is sensible.
Self-care at home
While you wait to be seen, or for mild cases, a few simple measures can ease symptoms. Rest the finger from repetitive or forceful gripping, and adjust how you hold tools with thick or padded grips so you do not squeeze so hard. A splint that keeps the affected finger straight, particularly overnight, can reduce the morning catching for some people. Gentle finger and tendon-gliding stretches help maintain movement; avoid forcing a locked finger straight, as this can be painful. If you have diabetes, keeping your blood sugar well controlled is worthwhile, as the condition is more common and more stubborn when sugars run high.
What to expect from a steroid injection or surgery
A steroid injection is a quick clinic procedure; some tenderness afterwards is normal, and people with diabetes should expect a temporary rise in blood sugar for a couple of weeks. A pulley release is usually day surgery under local anaesthesia, so you go home the same day, and most people regain smooth movement quickly. Keep the wound clean and dry as advised. For eligible day-surgery procedures, MediSave may help with part of the cost; check your eligibility and the likely out-of-pocket amount with your provider beforehand.
Common questions
Will trigger finger go away on its own?
Mild cases sometimes settle with rest and splinting, but persistent locking usually needs an injection or a quick release procedure.
Why does my doctor say injections work less well for me?
Injections are less reliable in people with diabetes, longstanding cases, and when several fingers are affected, so surgery may be discussed sooner.
Is surgery a major operation?
No. It is a common day-surgery procedure under local anaesthesia with a high success rate and a small palm incision.
Related guides
- Best Orthopaedic Clinics in Singapore — our editorial shortlist
- orthopaedic clinics directory
- Carpal tunnel syndrome
- Tennis & golfer's elbow
- Scoliosis
Sources
- SingHealth – Trigger Fingers
- OrthoInfo (AAOS) – Trigger Finger
- Raffles Medical Group – Trigger Finger
- National University Hospital – Hand and Wrist Conditions
Related conditions & guides
Related conditions and guides you may find useful:
Part of our Bones, joints, spine & sports guides · Browse all health topics