Trigger finger is a condition that affects one or more of the hand’s tendons, making it difficult to bend the affected finger or thumb.
Trigger finger is also known as stenosing tenosynovitis or stenosing tenovaginosis. It usually affects the thumb, ring finger or little finger. One or more fingers can be affected, and the problem can develop in both hands.
Symptoms can include
- pain at the base of the affected finger or thumb when you move it or press on it
- stiffness or clicking when you move the affected finger or thumb, particularly first thing in the morning.
- if it worsens the finger may get stuck in a bent position and then suddenly pop straight. Eventually, it may not fully bend or straighten.
What causes trigger finger?
Tendons are tough cords that join bone to muscle. They move the bone when the muscle contracts. In the hand, tendons run along the front and back of the bones in the fingers and are attached to the muscles in the forearm.
Trigger finger occurs if there’s a problem with the tendon or sheath, such as inflammation and swelling. The tendon can no longer slide easily through the sheath and can bunch up to form a small lump (nodule). This makes bending the affected finger or thumb difficult. If the tendon gets caught in the sheath, the finger can click painfully as it’s straightened.
Another hand-related condition called Dupuytren’s contracture can also increase your risk of developing trigger finger. In Dupuytren’s contracture, the connective tissue in the palm of the hand thickens, causing one or more fingers to bend into the palm of the hand.
Long-term conditions, such as diabetes and rheumatoid arthritis, are also sometimes associated with trigger finger.