What is it?
Trigger finger is a painful condition in which a finger or thumb clicks or locks as it is bent towards the palm.
What is the cause?
Wear and tear causes a thickening and roughness to the tendon surface, the tendon then catches when running through the tunnel mouth. People who are insulin-dependent diabetics are especially prone to triggering, but most triggering digits occur in people without diabetes. Triggering occasionally appears to start after an injury such as a knock on the hand.
There is not a lot of evidence to suggest that it is caused by work activities, but the pain can certainly be aggravated by hand use at work, at home, in the garden or at sport. People who suffer from Rheumatoid arthritis can also be prone to nodules causing triggering.
What are the symptoms?
- A nodule can be felt at the base of the effected digit.
- Tenderness if you press on the site of nodule.
- Clicking of the digit during movement, or locking in a bent position, often worse on waking in the morning. The digit may need to be straightened with pressure from the opposite hand.
- Stiffness, especially in trigger thumb where movement at the end joint is reduced.
Conservative Management:
Trigger finger / trigger thumb is not harmful, but can be a really painful. Some mild cases recover over a few weeks without treatment. The options for treatment are:
- Modifying or avoiding activities where possible that irritates the trigger.
- The use of a small splint or tape can help block the trigger and rest the affected tendon. A hand therapist can help support you with this.
- Massage of the nodule to loosen soft tissue
- Icing at the nodule to reduce inflammation.
Steroid Injections
Steroid injections have been found to relieve the pain and triggering in about 70% of cases, but the success rate is lower in people with diabetes.
The risks of injection are small, but it very occasionally causes some thinning or colour change in the skin at the site of injection. Improvement may occur within a few days of injection, but may take several weeks. A second injection is sometimes helpful, but surgery may be needed if triggering persists.
Surgery
Should conservative measures and injection management fail to be of benefit then a minor surgery can be completed. A small incision is made at the base of the digit and the mouth of the tendon tunnel is released to allow the tendon to move freely. The wound will require a small dressing for 10-14 days, but light use of the hand is possible from the day of surgery and active use of the digit is encouraged to prevent complications. Although the scar may be red and tender for several weeks, it is seldom troublesome in the longer term. You will need to massage the scar to help smooth the scar tissue down. Recurrence of triggering after surgery is uncommon but can occur.
