Trigger Finger

An often painful condition, trigger finger is caused by a narrowing of the sheath that surrounds the tendon in the affected finger. People whose work or hobbies require repetitive gripping actions are most susceptible to this condition. Trigger finger is also more common in women than in men, and in anyone with diabetes.  Treatment of trigger finger, also known as stenosing tenosynovitis, varies depending on the severity of the condition. Treatment ranges from rest to medications to surgery.

Signs and symptoms

At first, your affected finger may seem stiff and may click when you move it. You may notice a bump (nodule) or tenderness at the base of the affected finger in your palm. This is the spot where the tendon is likely catching.

As trigger finger worsens, your finger may catch at times in a bent position and then suddenly pop straight. Eventually, the finger may not fully straighten. Trigger finger is not the same as Dupuytren's contracture — a condition that causes thickening and shortening of the connective tissue in the palm of the hand — though it may occur in conjunction with this disorder.

Trigger finger most often affects your thumb or your middle or ring finger. More than one finger may be affected at a time, and both hands might be involved. Triggering is usually more pronounced in the morning, while firmly grasping an object or when straightening your finger.

Causes

The cause of trigger finger is a narrowing of the sheath that surrounds the tendon in the affected finger. Tendons are fibrous cords that attach muscle to bone. Each tendon is surrounded by a protective sheath — which in turn is lined with a substance called tenosynovium. The tenosynovium releases lubricating fluid that allows the tendon to glide smoothly within its protective sheath as you bend and straighten your finger — like a cord through a lubricated pipe.

But if the tenosynovium becomes inflamed from repetitive strain injury or overuse or due to inflammatory conditions, such as rheumatoid arthritis, the space within the tendon sheath can become narrow and constricting. The tendon can't glide through the sheath easily, at times catching the finger in a bent position before popping straight. With each catch, the tendon itself becomes irritated and inflamed, worsening the problem.

Risk factors

If you routinely grip an item — such as a power tool or musical instrument — for extended periods of time, you may be more prone to the development of a trigger finger. You're also at greater risk if you have certain medical conditions, including rheumatoid arthritis, diabetes, hypothyroidism, amyloidosis and certain infections — including tuberculosis and sporotrichosis, a fungal infection that usually affects the skin. Trigger finger is also more common in women than in men.

When to seek medical advice

Bring any stiffness or catching in a finger joint to the attention of your doctor so that he or she may review your symptoms and perform a physical evaluation of your hand. Seek immediate medical care if a finger joint is hot and inflamed because this may indicate an infection.

Treatment

Treatment for trigger finger varies depending on its severity and duration.

Treatment of mild cases

For mild or infrequent symptoms, these approaches may be effective:

• Rest. You may notice improvement simply by resting the affected hand. To prevent the overuse of your affected finger, your doctor may also suggest you change or curtail work or personal activities that require repeated gripping actions.
• Splinting. Your doctor may have you wear a splint to keep the affected finger in an extended position for several weeks. The splint helps to rest the joint. Splinting also helps prevent you from curling your fingers into a fist while sleeping, which can make it painful to move your fingers in the morning.
• Finger exercises. Your doctor may also suggest that you perform gentle exercises with the affected finger. This can help you to maintain mobility in your finger.
• Soaking in water. Placing the affected hand in warm water for five to 10 minutes, especially in the morning, may reduce the severity of the catching sensation during the day. If this helps, it can be repeated several times throughout the day.
• Massage. Massaging your affected fingers may feel good and help relieve your pain, but it won't affect the inflammation.

Treatment of more serious cases

For more serious symptoms, your doctor may recommend other approaches, including:

• Nonsteroidal anti-inflammatory drugs (NSAIDs). Medications such as nonsteroidal anti-inflammatory drugs — ibuprofen (Advil, Motrin, others), for example — may relieve the inflammation and swelling that led to the constriction of the tendon sheath and trapping of the tendon, and can relieve the pain associated with trigger finger.
• Steroids. An injection of a steroid medication, such as cortisone, near or into the tendon sheath also can be used to reduce inflammation of the sheath. This treatment is most effective if given soon after signs and symptoms begin. Injections can be repeated if necessary, though repeated injections may not be as effective as the initial injection.
• Percutaneous trigger finger release. In this procedure, which is performed under local anesthesia, doctors use a needle to release the locked finger. Combining this procedure with a steroid injection may make it even more effective.
• Surgery. Though less common than other treatments, surgical release of the tendon may be necessary for locking that doesn't respond to other treatments.