What is trigger finger?

Trigger finger is a condition that affects a large portion of people over the age of 50. It is characterized by a "locking" of one or more fingers in a flexed position after fully closing the hand. The person is unable to open the fingers, and after a few moments of pain, is finally able to extend them.

Symptoms

The condition usually appears in the morning and improves throughout the day. It may be related to excessive hand use the previous day.

Incidence

More common in female patients over 50 years old. The thumb and ring finger are the most frequently affected.

Causes

Our flexor tendons are cylindrical structures that connect the flexor muscle (located in the forearm) to the finger phalanges. Each long finger has two flexor tendons, and the thumb has one. At the end of the palm, these tendons pass through a tunnel that keeps them close to the bones. When these tendons suffer trauma, they become swollen and lose their cylindrical shape.

Diagnosis

Diagnosis is based on the patient’s history and clinical examination. It can be confirmed with a simple ultrasound exam. Trigger finger is classified into four types:

when there is only a snapping sensation at the entrance of the osteofibrous tunnel without locking
when locking occurs, but the patient can extend the finger without assistance
when locking occurs and the patient needs to use the other hand to "release" the finger
when the patient is unable to extend the finger at all

Treatment

Treatment involves reducing tendon swelling or enlarging the tunnel. Tendon thickening can be reduced with locally applied corticosteroid injections (used for types 1 to 3). When injections fail, are frequently needed, or in type 4 cases, surgical release of the tunnel is required. The surgery is done in an outpatient setting, performed under local anesthesia, and recovery is quick

By Einstein Editorial Board