"Trigger finger" sounds like a malady that might affect gunslingers or hunters. In fact, this common condition results in a finger bent as if to pull a trigger. People over 40 years of age with a history of diabetes or rheumatoid arthritis are especially at risk of developing this condition.

Causes
Although the exact cause of trigger finger is unknown, its effects are well documented. Trigger finger involves the tendons and pulleys in the hand that bend the finger. The tendons connect the muscles of the forearm with the bones of the fingers. Each tendon is covered by a slick lining or sheath. When you bend your fingers, the tendons glide back and forth, guided by a restraining pulley or yoke.

When the tendon sheath becomes inflamed, it swells and may develop a knot or thickening in the tendon. The knot passes through the pulley as the finger bends, but gets stuck as the finger straightens. This causes further irritation and results in a vicious cycle of irritation, swelling, catching and more irritation until finally, the finger locks in a bent position.

Symptoms
The most common symptom of trigger finger is a painful clicking or snapping when attempting to flex or extend the affected finger. There may also be soreness at the base of the finger or thumb. In some cases, the involved finger or thumb locks in a flexed position, or in an extended position as the condition becomes more severe, and must be gently straightened with the other hand. Joint contraction may eventually occur.

Treatment
Treatment aims to reduce swelling and eliminate catching. Initial treatment is usually conservative, involving rest, splinting the extended finger, and taking aspirin or ibuprofen to reduce swelling and ease pain.

If symptoms persist, your physician may administer a steroid injection in the tendon sheath. Although there may be some short-term discomfort from the injection, it can relieve the pain and locking for several months.

People with diabetes and rheumatoid arthritis will probably require surgery to release the tendon. The surgery is done on an outpatient basis and can restore active motion immediately. However, hand therapy may be needed to regain better use of the finger(s).