Trigger finger or trigger thumb
Triggering of the digit is a condition which can present in a couple of ways. In some patients the finger or thumb may become stuck or locked in a bent position. Once stuck, patients often use their other hand to straighten it.
This can be painful as it springs back into position with a click. In others the finger or thumb can feel stiff, painful and not fully bend. If it occurs relatively frequently it can be annoying as it interferes with everyday hand function.
Why does it occur?
The tendons that enable the finger or thumb to bend run in an intricate pulley system or tunnel. If a nodule or swelling develops on the tendon, this can disrupt the smooth gliding action of the tendon within the pulley system.
Since the tendons that bend the finger are relatively strong compared to the tendons that straighten the finger, the swelling can be pulled through the tunnel in one direction. Once through, the swelling snags on the edge of the tunnel causing the finger to remain bent and needing extra force to straighten it.
Who gets it?
Trigger finger presents in a range of age groups. It can also present in babies. Usually it resolves in this young age group without the need for surgery. However it is important monitor it.
Associated diseases include diabetes, dupuytrens disease and rheumatoid arthritis.
Treatment for trigger finger or trigger thumb
Not all triggering is severe enough to warrant intervention. If it occurs very occasionally with minimal discomfort a more conservative approach to treatment is sensible.
For those with more troublesome symptoms, steroid injections into the finger or palm improve the situation in about 80% of patients. They usually take a couple of weeks before any improvement is noticed. Repeat steroid injections can be given to a limit.
If steroid fails to control the symptoms or wears off after a short period of time then a surgical release of part of the pulley system can be undertaken under a local anaesthetic.
Risks of surgical treatment
- Incomplete release or recurrence – recurrence is rare following surgery but occurs in approximately 10 to 20% of patients following steroid injection
- Nerve damage
- Pain reaction in the hand (very rare)