What is trigger finger?
Each finger has two tendons that make it bend. The thumb has a single tendon. These tendons run in a tight tunnel (flexor tendon sheath) that allows the tendons to glide and move in the correct direction.
The tendon sheath may become too tight due to irritation, overuse or without an obvious reason. This makes it difficult for the tendon to glide smoothly, making it bunch up. The bump in the tendon then further inhibits tendon gliding.
A trigger finger is caused by a bump in the tendon snapping through part of the tendon sheath. This causes (painful) clicking or locking of the finger in a bent position (triggering).
Treatment for trigger finger
Treatment of a trigger finger can start with splinting or a steroid injectionin the tendon sheath. If that fails, part of the sheath can be surgically released to allow the tendon to glide freely again.