Some tendons, especially those that move fingers and thumb, are covered by a membrane that allows free movement of the tendon. The synovial membrane may get inflamed and swell, especially if you repeat some action with your fingers – for example, typing on a typewriter. Over time, the membrane will heal, but may become too tense or narrow.
A tense synovial membrane limites the movement of the tendon it covers, and the consequence of this disorder is called tenosynovitis. An example of the consequence of this inflammation is the lighter discomfort called a “snapping finger”; in this disorder, the narrowing of the synovial membrane makes it difficult to stretch the fingers. The mechanism for ”stretching” the fingers stops for a few moments, and then the tendon suddenly overcame the obstacle and the finger ends the movement with a sudden twitch. In such cases, the area above the tendon is painful and sensitive, the finger hurts, and when the obstacle is overcome, a silent tick is heard.
In addition to mechanical factors, tenosynovitis is sometimes caused by infections. In such cases your finger is very painful and almost unusable, and you may have other symptoms and feel generally ill.
What to do?
If symptoms indicate the possibility of infection, contact your doctor immediately. It will be necessary to treat antibiotics, and perhaps a surgical procedure to remove the dung that bacteria produce. Unpleasant noninfectious tenosynovitis is sometimes treated with corticosteroid injections. If the condition persists, a simple operation is performed, i.e. straining of a narrowed synovial membrane that will re-enable the free movement of the tendon.