Trigger finger occurs when a small nodule forms on one of the tendons that control finger movements. These tendons are held in position by a complex system of pulleys. When the nodule thickens, it becomes stuck in one of the pulleys, causing the finger to be locked in a bent position. The finger suddenly pops out straight when the patient tries to extend it (like a gun’s trigger being pulled and released).
Even if some improvement can be expected with the conventional treatment (finger immobilization), a medical or surgical treatment is required most of the time. A local corticosteroid injection is also possible. Often, this significantly improves the symptoms. The surgical treatment, carried out under local anesthesia, consists of a small incision at the base of the finger, which opens the pulley responsible for the locking.