What is trigger finger?
Later, this may progress to a sense of catching as the affected finger is flexed and extended. This catching may be painful. Eventually, the catching may be so severe that it is impossible to flex or straighten the finger without help from the other hand. The finger becomes unstuck suddenly, and this is the “triggering” that gives the condition its name.
Trigger finger is also known as “trigger thumb” when it affects the thumb.
What causes trigger finger?
As the flexor tendon from the forearm to the finger passes through the palm of the hand, it passes through various tunnels, known as pulleys. These help guide the tendon to the correct finger. Trigger finger occurs when the tendon develops a lump which catches and irritates the pulley in the palm. As the irritation increases, the area becomes more swollen, leading to further tightening and irritation.
This then becomes a vicious circle of inflammation – pain – swelling – inflammation – etc.
It may be related to certain other conditions, such as diabetes, inflammatory arthritis (eg. rheumatoid arthritis), partial tendon lacerations, or highly repetitive work, but in most cases, no known cause is found for the condition.
How is trigger finger diagnosed?
Trigger finger is diagnosed from the patient’s history and the examination. Generally, further tests are not required.
How is trigger finger treated?
The crux of non-surgical treatment is to break the cycle of inflammation and pain. These are often best used in combination.
Various options include:
Rest – A splint fitted by a hand therapist can help rest the finger by keeping it still.
Anti-inflammatory tablets or creams.
A cortisone injection is very good at settling inflammation and swelling, and thus relieving pain. This may need repeating once to fully resolve the symptoms.
Surgery is recommended if the finger is locking in position, or if other treatment fails.
Surgery is performed via a small incision in the palm of the hand, and the pulley is released where the tendon is catching.
Surgery is done as a day-only procedure in a hospital. It can be performed under local anaesthetic with the patient awake, or under general anaesthesia with the patient asleep. The advantage of doing this under local anaesthesia is being able to have the patient bend the finger during the operation to ensure the triggering has fully resolved once the pulley has been released.
What to expect after the operation:
A bulky dressing will be applied to the surgical site in the operating room at the end of the operation. This should be kept dry and elevated until your follow-up appointment in about 10 days.
Sometimes, a hand therapist to helpful to assist with regaining motion and strength.
Despite the small incision, soreness at the operative site usually persists for a while and it often takes 3 months to return to full activities.
What are the risks of surgery?
Complications from trigger finger surgery are uncommon. The usual risks are:
- Nerve, tendon or blood vessel damage
- Ongoing pain
- Persistent triggering is rare
- Recurrent triggering is rare. However, it may occur in other fingers, especially if there is a general underlying medical cause, such as diabetes or rheumatoid arthritis
- Complex regional pain syndrome.