Trigger finger (also known as stenosing tenosynovitis) is a condition of the tendon, a strong, flexible band that connects muscle to bone. The tendons in your hand pass through a protective tunnel, or sheath, that runs from your forearm to your fingers. The sheath has a special lining that lubricates the area.
Normally, tendons glide smoothly in your hand to move your fingers, but with trigger finger, the synovial lining becomes inflamed and swells. This in turn narrows the space around the tendon, which then rubs against the lining, becoming irritated and swollen. A nodule (knot) develops in the area, which further restricts passage of the tendon. The result is a finger or thumb that catches when you attempt to straighten it, and then releases with a rapid "triggering" motion.
The cause of trigger finger is not always known but it often results from excessive use and stress on the tendons. Vibration also seems to be a factor, as well as diseases such as rheumatoid arthritis, diabetes and gout.
You will probably experience some pain and swelling at the base of your finger or thumb. You may also feel a knot in the area. The joint may be stiff and your finger or thumb may pop, catch or lock when you straighten it.
Conservative treatment usually includes a period of rest for the finger or thumb. An ice pack may be applied thre to four times per day for 10 to 15 minutes at a time to control swelling and pain. Your doctor may also recommend anti-inflammatory medications or a steroid injection to reduce inflammation.
Outpatient surgery may be recommended for more serious cases. The surgeon will make an opening in the sheath to prevent the tendon from catching. Following surgery, you will need to limit the activity of the affected finger or thumb for a few days. Your doctor may refer you for specialized hand therapy and exercise during your rehabilitation.
Typically, patients recover fully without complications from trigger finger. If you plan to have surgery for the problem, talk with your doctor about the risks of infection, scarring, joint stiffness and nerve damage. Your recovery will depend on your age, overall health and the extent of your condition.
Generally, trigger finger cannot be prevented, but taking good care of your wrist and hands may decrease your chances of developing the condition. Taking rest breaks, using appropriate hand tools and proper body mechanics are good measures for reducing the possibility of trigger finger.