Trigger finger is a painful condition in which any finger, including the thumb, becomes stuck in a bent position as if holding onto a trigger. After becoming locked in place, the finger may snap back into a straight position as if a trigger is being released. It usually affects the thumb or ring finger, though it can affect any finger. Trigger finger is also known by the medical term Stenosing Tenosynovitis.
Trigger finger begins in the tendons that bend the fingers and the connective tissues that hold those tendons close to the finger bones. These tendons normally glide smoothly through the sheath that surrounds them. However, sometimes these sheaths swell and narrow, and the tendon can’t move within it easily. When this happens, the tendon can get stuck in the sheath, causing pain, popping, or causing a catching feeling in the finger or thumb. As the tendon repeatedly catches, the swelling and irritation grows, which causes the tendon to catch even more.
Trigger finger is also more common in people who, for work or play, use their fingers or thumbs in ways that require strenuous repetitive motions. And it is common for activities that require frequent, strong grasping or gripping, or forceful use of the fingers and/or thumb. These people may include farmers, musicians, or industrial workers. It also may be common for people who have osteoarthritis, rheumatoid arthritis, gout, or diabetes. It usually affects people between the ages of 40 and 60.
The symptoms of trigger finger may progress from mild to severe and include:
- Finger or thumb stiffness, particularly in the morning.
- Snapping or popping sensations when moving the finger(s) or thumb.
- Soreness at the base of the affected, especially while gripping or grasping.
- Finger catching or locking in a bent position, which suddenly pops straight
- Pain and stiffness when bending the finger(s) or thumb.
- Inability to fully flex the finger.