Trigger Finger (Stenosing Flexor Tenosynovitis)

• Trigger finger is a form of tendinitis (tendon inflammation).
• Tendon inflammation and swelling prevents the tendon from sliding easily in the tendon sheath, which causes "triggering" of the finger as it snaps to flex or extend.
• Risk factors for trigger finger include diabetes, rheumatoid arthritis, and repetitive movements.
• A corticosteroid (cortisone) injection around the affected tendon usually relieves the symptoms of trigger finger.
• Surgery can cure trigger finger that does not respond to other treatments.

Trigger finger is a form of tendinitis whereby a finger can become fixed in a flexed position, as if that finger is pulling a trigger. Trigger finger is also known as stenosing flexor tenosynovitis.

Picture of trigger finger

Trigger finger is caused by inflammation of the tendon that bends the finger (flexor tendon). The inflammation causes swelling of the tendon and sometimes scarring with a nodule or lump on the tendon. The tendon then is too thick to slide easily in the tendon sheath and it sticks. This can cause snapping as the tendon is forced through the tendon sheath when the finger is bent and extended to straighten. A rare complication of severe trigger finger is the finger becoming stuck in a fixed bent position.

Risk factors for trigger finger include the following:

• Activities that cause pressure across the joints at the top of the palm of the hand, such as tight gripping and grasping and operating vibrating machinery
• Repetitive movements that flex the affected finger multiple times
• Female gender: Women develop trigger finger more commonly than men.
• Certain health conditions such as diabetes and rheumatoid arthritis increase the risk of trigger finger

Signs and symptoms of trigger finger may be mild or more severe as the problem worsens. Signs and symptoms include

• finger pain that can extend from the base to the tip of the finger;
• stiffness of the affected finger in the morning;
• tenderness, or a nodule (bump) in the palm of the hand at the base of the affected finger;
• popping, snapping, or clicking as the finger bends and straightens;
• inability to fully flex the finger;
• severe trigger finger can cause the affected finger to lock in a fixed, flexed position, requiring the use of the opposite hand to pull it straight.

The diagnosis of trigger finger is made on the basis of the symptoms of pain and sticking of the finger and by examination of the hand. X-rays are not necessary to diagnose trigger finger but may be used to exclude other conditions that cause hand pain.

With mild trigger finger, resting the finger may be the only treatment needed. Gentle massage, stretching of the finger, followed by cold application can often relieve mild trigger finger. For more rapid relief, an injection of corticosteroids (cortisone), such as methylprednisolone (Depo-Medrol), is administered into the tendon sheath to reduce the swelling and inflammation. A single corticosteroid injection for trigger finger relieves symptoms up to 85% of the time. If the injection is ineffective, another injection may be given three to six weeks later.

If the corticosteroid injections are ineffective, then surgery to open the constricted tendon area may be necessary. Surgical repair procedure for trigger finger is referred to as a trigger finger release. This operation is performed by a specialist such as an orthopedic surgeon or orthopedic hand surgeon.

Rest, cold application, and splinting may be helpful for mild trigger finger. Gently massaging a nodule at the base of the finger may help break up the scar tissue and relieve the pain. For more severe trigger finger, an injection around the affected area will usually bring relief. Exercises may worsen the problem by increasing inflammation.

NSAIDs (nonsteroidal anti-inflammatory medications such as ibuprofen [Advil) and naproxen sodium (Aleve, Naprosyn)] can be helpful for pain but are unlikely to resolve the underlying problem.

With treatment, the prognosis of trigger finger is very good. Available treatments for trigger finger are very effective at relieving the problem. However, trigger finger may recur after corticosteroid (cortisone) injection and require further treatment.

One can prevent trigger finger by limiting repetitive movements and excessive pressure on the tendons in the hand. If the finger is rested when the symptoms are mild, the condition may improve and resolve rather than progressing.