Trigger Finger - Causes, Symptoms, Treatment and Prevention

Tendons are important structures for moving our fingers. In trigger finger, the lining of the tendon swells and the tendon is not able to glide smoothly. This is a condition where there is a locking or clicking of the thumb or fingers when they are actively bent or straightened, often accompanied by joint pain and stiffness.

The condition is caused by inflammation and swelling of the thumb or finger tendon (tendon nodule), reducing its ability to glide through its sheath during thumb or finger movements. This results in pain or a catching feeling when you try to move your finger. You may feel a bump or tenderness over the palm at the base of the finger, where the enlarged nodule is.

Trigger finger occurs when the tendons in your finger or thumb become inflamed, leading to irritation as they pass through the sheath that surrounds them. This inflammation causes the tendon to thicken, making it difficult to move smoothly.

Over time, this results in the characteristic locking or catching sensation. The underlying cause is the repeated friction or stress on the tendons, often due to frequent gripping motions or hand use. Forceful and repetitive use of the hand in daily activities can lead to trigger finger; for example, wringing towels, carrying heavy groceries, forceful gripping of tools.

Whilst anyone can develop trigger finger, those engaged in activities that strain the hand muscles are more likely to experience this condition.

Factors that increase a person's risk of developing trigger finger include:

Being 40 years old and over: Individuals over the age of 40 are more likely to develop trigger finger due to tendon wear.

Females: Women have a higher risk, possibly due to hormonal factors affecting tendon flexibility.

Engaged in repetitive hand use: Activities like gripping tools or playing instruments increase tendon strain.

Certain medical conditions: Trigger finger can be associated with medical conditions like diabetes (Type 2 Diabetes Mellitus), gout and rheumatoid arthritis (RA), which raise the likelihood of tendon inflammation.

Having a previous hand injury: A history of hand trauma can increase susceptibility to trigger finger.

Trigger finger typically develops gradually, with symptoms that can range from mild to severe. The condition primarily affects the tendons in your fingers or thumb, causing discomfort and restricted movement. Below are the key symptoms to watch out for:

Stiffness in the finger: One of the earliest symptoms is stiffness, particularly in the morning. The affected finger may feel tight or difficult to move, especially when attempting to bend or straighten it.

Clicking or popping sensations when moving the affected finger: As the condition progresses, you might notice a clicking or popping sensation when moving your finger. This is caused by the tendon catching as it moves through the sheath, leading to a feeling of resistance.

Pain or tenderness in the finger: Pain is a common symptom and can occur at the base of the affected finger or thumb. The area may also become tender to the touch, making gripping objects or using the hand uncomfortable.

Swelling or a lump on the finger: A small bump or nodule may develop at the base of the affected finger. Swelling may also occur, making it harder for the tendon to move smoothly within the sheath.

Finger has limited range of motion: Over time, the range of motion in the affected finger may become limited. Everyday activities such as gripping, writing or typing may become more difficult and painful.

Finger locked in a bent position (advanced cases): In more advanced cases, the finger may lock in a bent position and be difficult to straighten. In some instances, the finger can only be moved with assistance or considerable effort, causing significant discomfort.

If you experience any of these symptoms, it is important to seek medical advice early, especially if the condition begins to interfere with daily activities. Early treatment can help prevent further complications.

Seek medical attention if:

• Your finger becomes locked in a bent position and cannot be straightened
• Pain or discomfort increases over time
• You have difficulty performing daily activities due to stiffness or pain
• A lump or noticeable swelling develops at the base of your finger
• Home treatments like rest or splinting do not improve the symptoms

Trigger finger is typically diagnosed through a physical examination. In most cases, no additional tests like X-rays or scans are required, as the condition can be diagnosed based on symptoms and hand movement alone. However, if there is concern about underlying conditions, your doctor may order further tests.

Based on the examination, a grade will be assigned to your trigger finger or thumb based on the severity of your condition:

Grade 1: Mild discomfort and occasional locking.

Grade 2: Locking occurs during physical examination, but you can still straighten your finger or thumb.

Grade 3: Difficulty bending or straightening your finger or thumb, interfering with daily activities.

Grade 4: Finger or thumb is stuck in a bent position, causing significant pain.

Treatment approaches vary depending on pain level and the affected area (tendon or muscle in forearm):

For Severe Pain:

• Tendon: Cold compression to painful area to reduce pain and swelling. Wear splint as advised by your therapist and rest.
• Muscle (Forearm): Heat therapy over muscles and massage.

For No or Slight Pain:

• Tendon: Heat therapy (hot pack/warm towel), stretching exercises, wear splint when doing daily activities and when sleeping at night.
• Muscle (Forearm): Heat therapy and massage.

Non-Surgical Treatment Options

• Hand therapy
• Wearing a splint
• Anti-inflammatory medications
• Steroid injection to the finger

Surgical Treatment

If symptoms persist, surgery is recommended. Trigger finger surgery is usually a minor procedure performed under local anaesthesia, which involves the release of the tendon tunnel to create more space.

With surgical intervention, there is a less than 5% chance of trigger finger recurring.

Whilst it may not always be possible to completely prevent trigger finger, you can reduce the risk of it happening by taking some precautions:

Avoid repetitive hand strain: Try to limit activities that require frequent gripping or forceful hand movements. Avoid repetitive gripping movements during daily activities (e.g. avoid handwashing of clothes, wringing of washcloths).

Give your hand(s) regular breaks: If your job or hobby involves repetitive hand use, taking breaks can help minimise tendon strain. Take frequent rest breaks in activities that require repetitive gripping or squeezing.

Use ergonomic tools: Tools designed to reduce pressure on your hands can help reduce the risk of tendon irritation.

Stretch and strengthen your hands: Regular hand exercises can help maintain tendon flexibility and strength.

Manage underlying conditions: Properly managing conditions like diabetes or arthritis may reduce the risk of developing trigger finger.

Reduce forceful movements: Reduce or avoid forceful gripping and pinching movements during activities.

Avoid heavy loading: Avoid heavy loading and carrying plastic bags over different fingers.

Alternate tasks: Alternate between strenuous and easier tasks, switch hands if possible.

These preventive measures can help lower your chances of developing trigger finger, especially if you are at higher risk.