What is trigger finger?
Trigger finger, medically known as stenosing tenosynovitis, is a common condition affecting the flexor tendons of the hand. These tendons are responsible for bending the fingers and thumb, allowing for gripping and fine motor movements. Normally, the tendons glide smoothly within a protective sheath that is reinforced by a series of fibrous bands called pulleys, which hold the tendon close to the bone. In trigger finger, inflammation or thickening of the tendon or its sheath disrupts this smooth gliding motion. As a result, the tendon may catch or become momentarily stuck as the finger bends and straightens. In more advanced cases, the finger may lock in a flexed (bent) position and require assistance to extend.
Causes
The exact cause of trigger finger is not always clear, but several factors are known to increase the risk. Repetitive hand use—particularly activities involving strong gripping, prolonged grasping, or the use of vibrating tools—can contribute to irritation of the tendon. Certain medical conditions are also associated with a higher incidence of trigger finger. These include diabetes, inflammatory arthritis (such as rheumatoid arthritis), and other conditions that affect connective tissue. It is also more common in middle-aged individuals and tends to occur more frequently in women. Despite these associations, many cases arise without an identifiable cause.
Symptoms
Symptoms often develop gradually and may worsen over time. Common features include:
- Pain or discomfort at the base of the affected finger or thumb, particularly when gripping or moving the digit
- A clicking, popping, or snapping sensation during finger movement
- Stiffness, especially in the morning or after periods of inactivity
- A palpable, tender nodule or lump in the palm, corresponding to the inflamed portion of the tendon
- Locking or catching of the finger during flexion and extension
In more severe cases, the finger may become stuck in a bent position and may need to be manually straightened, sometimes with a sudden snap that can be painful.
Diagnosis
Diagnosis of trigger finger is primarily clinical and is based on the patient’s history and physical examination. Your surgeon will assess for characteristic signs such as tenderness over the tendon sheath, the presence of a palpable nodule, and reproducible triggering during finger movement. In most cases, no additional tests are required. The condition is typically straightforward to identify based on these findings.
Imaging
Imaging studies are not routinely necessary for diagnosing trigger finger. However, in uncertain or atypical cases, ultrasound imaging may be used to visualise the tendon and its sheath. Ultrasound can sometimes demonstrate thickening of the tendon, inflammation, or narrowing of the pulley system. Other imaging modalities, such as MRI, are rarely required and are generally reserved for complex or unclear presentations.
Treatment
Conservative (Non-operative)
Management of trigger finger depends on the severity of symptoms and their impact on daily activities. Initial treatment is usually conservative and may include activity modification to reduce or avoid movements that aggravate symptoms, splinting of the affected finger—particularly at night—to rest the tendon and limit triggering, and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) to help reduce pain and inflammation. Corticosteroid injections into the tendon sheath are also commonly used and can be highly effective in reducing inflammation and restoring smooth tendon movement. Many patients experience significant improvement with these non-surgical measures, particularly when treatment is started early.
Surgical treatment
If conservative treatments fail to provide relief, or if the finger is persistently locked, surgical intervention may be considered. Trigger finger release surgery is a relatively simple and commonly performed procedure. During the operation, the surgeon releases (cuts) the affected pulley—most often the A1 pulley—to allow the tendon to glide freely again. This is performed through a small incision in the palm.
Recovery
Recovery is generally quick, with most patients regaining full finger movement shortly after the procedure. Hand therapy may occasionally be recommended to restore strength and flexibility. Complications are uncommon but may include infection, stiffness, or incomplete symptom relief.