Trigger Finger

What is Trigger Finger?

Trigger fingers are a very common orthopaedic condition of the hand. They are a result of the tendons of the finger swelling underneath the pulleys in the hand. Pulleys are soft tissue structures that help the tendons achieve a mechanical advantage with flexion of the fingers. They accomplish this by essentially holding the tendon against the finger; without the pulleys, our tendons would “bowstring” out of place with flexion and be very weak. The progression of a trigger finger generally unfolds as follows. The first pulley of the flexor tendon becomes stiff and less compliant, which causes the tendon to no longer fit under the pulley leading to swelling and irritation. Inflammation on the tendon can cause the tendon to get stuck as it travels underneath the pulley. This catching, or “triggering,” of the tendon is where the name comes from. Thus begins the cycle of triggering and swelling, which causes and worsens trigger fingers.

Symptoms & Causes

The most common symptoms of a trigger finger are pain and “catching” with movement through the range of motion of the fingers. Oftentimes, a painful lump in the palm can occur as well, marking the site of inflammation. However, catching of the finger does not have to be present for a patient to have a trigger finger. Pain with extension or gripping may be the only symptoms a patient experiences. In any case, symptoms are more common in the morning than throughout the rest of the day.

Affected Populations

Trigger fingers are common in men and women over the age of 35. Patients with one trigger finger are at increased risk of developing another trigger finger and also at increased risk for developing carpal tunnel syndrome. Trigger fingers can also be associated with certain comorbidities like diabetes and rheumatoid arthritis and are very common in people whose occupations or hobbies cause irritation of the flexor tendons.

Treatment

Unfortunately, studies have shown that trigger fingers often do not respond to non-surgical interventions like splints, non-steroidal anti-inflammatory drugs (NSAIDs), and physical therapy. However, a single steroid injection may be curative in 50-75% of cases, but this intervention is less effective in patients that have more than one finger affected, or are experiencing a recurrence following a previous injection. Surgical treatment, known as a trigger finger release, is a definitive treatment and is required if someone has failed an injection, has rheumatoid arthritis or has insulin-dependent diabetes. Surgery is done under local anesthesia to ensure the complete release and requires a surgeon to release the pulley that is causing irritation of the tendon. This release allows the tendon to once again move freely underneath the pulley, ending the cycle of catching and swelling.

Trigger Finger Extended