What is trigger finger and what causes it?

Inflammation.: The tendons that help bend the fingers run inside a system of pulley's called the flexor tendon sheath. The first pulley, the a1, can become narrowed. This causes friction and inflammation, leading to catching and popping of the digit. This is triggering and can be treated with oral/injectable steroids and therapy. See a board certified orthopaedic hand surgeon for evaluation and treatment.

Tendonitis: A trigger finger is form of tendonitis of the tendons that bend down the finger. They can cause just pain, just locking and catching or pain and locking. The most effective treatment is an injection of cortisone. This reduces the inflammation around the tendons. You have an approximately 70% chance of this going away with just injections. If not surgery is an option.

Trigger finger : can respond to ice and inflammatories. However if the problem is persistent it's been shown that between 47 and 90% of trigger fingers get better with a single solitary corticosteroid injection