Tendon sheath inflammation of the finger
Trigger finger can be an annoying and painful condition. It often involves one finger, but sometimes also several fingers, which contracts involuntarily. The finger or thumb gets stuck, as it were, and remains bent.
The flexors are located on the inside of the forearm. These ensure that you can grab something with your hand. On the other side of the forearm are the extensor muscles that extend the hand again. Tendons run from those muscles to your fingers. When the flexors contract, they bend your fingers through the tendons. With a trigger finger, your flexor tendon is irritated. When bending vigorously, the tendon can suddenly burst through. Hence the name trigger finger or ‘spring finger’.
What are the symptoms?
Bending or extending the finger produces a painful, uncomfortable feeling at the base of the finger. You can’t straighten the finger anymore because it’s jammed. With force, the finger can still be helped a bit further. You may only be able to bend or extend your finger by grasping and moving it with your other hand. Sometimes a bump forms in the tendon sheath that can slide back and forth when you bend or stretch your finger.
How does a trigger finger develop?
A jumping finger occurs when a tendon sheath is inflamed. Due to the inflammation, the tendon swells and the tendon sheath becomes narrower. This causes the tendon to become trapped. It is unknown what causes the tendon sheath to become inflamed. Women are more likely to suffer from trigger finger than men. It is also more common in children under the age of six, people between the ages of 40 and 70 and in people with diabetes mellitus, rheumatoid arthritis, an underactive thyroid or gout. It is more common in people who work a lot on a keyboard or play the piano.
Therapy
There’s not much you can do about a trigger finger. In most cases it is a matter of waiting to see if the complaints go away on their own. In some cases, an injection of an anti-inflammatory drug (corticosteroid) can help to reduce the pressure in the tendon sheath. After receiving an injection, it takes about two or three weeks to see if the symptoms decrease.
If little or nothing changes, the treating doctor may consider giving a second injection. There is no point in giving more than two injections. If the symptoms do not disappear, surgery may be considered. The tendon sheath is opened, so that the tendon has more room to move again.
Sources):
