Definition: Trigger finger is a common condition that causes pain and locking of the fingers. Trigger finger occurs when the tendons of the fingers become caught in the sheath in which they run.
Tendons are like ropes that attach to the ends of your fingers. When your muscle contracts, the flexor tendons pull the fingers into a fist. The tendons run part of their course through a sheath called the flexor tendon sheath. When a patient has trigger finger, this mechanism of movement is inhibited. Fortunately, there are effective treatments for a trigger finger.