Trigger finger

Disease Description (Causes and Symptoms)

• Definition: A condition in which the flexor tendon cannot glide (slide) and catches (sticking, clicking), suddenly straightens (snapping, trigger phenomenon), or becomes locked due to inflammation and narrowing of the tendon sheath (tenosynovium) or tendon covering surrounding the tendon. It mainly occurs at the A1 pulley.
• Causes/Risk factors:
  • No single exact cause is known. Repetitive, forceful gripping, exposure to vibration, and occupational exposure involving prolonged finger flexion increase the risk.
  • Associated with diabetes mellitus, rheumatoid arthritis, pregnancy, and age (over 40 years).
  • May be associated with a family history or other connective tissue abnormalities.
• Pathophysiology summary: When inflammation/fibrosis at the A1 pulley causes the tendon to thicken or form a nodule, the tendon catches or snaps as it passes through the narrowed passage.
• Main symptoms:
  • Pain and tenderness in the palm (at the base of the finger)
  • A catching sensation, clicking, or snapping when bending and straightening the finger
  • In severe cases, the finger remains in a bent position (locked)
  • Symptoms are often worse in the morning
  • Most commonly affects the third and fourth fingers

Treatment Methods

• Nonsurgical treatment (first attempted for mild or acute cases)
  • Activity modification: Avoid repetitive forceful gripping and vibration exposure; improve the work environment (replace tools, take breaks)
  • Orthosis (night splint): Prevent locking and flexion and encourage rest
  • Medication: NSAIDs (symptom relief), topical anti-inflammatory medication
  • Local steroid injection: Injected into the A1 pulley area. Many patients improve, but recurrence is possible. It may be less effective in patients with diabetes mellitus, and blood glucose changes need to be monitored.
    • Injection-related complications: Skin atrophy or pigmentation changes, injection pain, and, rarely, tendon weakening or rupture
  • Ultrasound-guided injection may improve accuracy
• Procedural/Surgical treatment (when conservative treatment fails or severe locking is present)
  • Percutaneous release: The A1 pulley is incised and released with a needle. Recovery is rapid, but there is a slight risk of nerve damage.
  • Open release: A small incision (about 1 cm) is made in the palm, followed by direct incision and release of the A1 pulley. It has high reproducibility and makes complication management easier.
  • Postoperative care: Early joint movement is recommended; monitor for infection, nerve damage, scarring, and joint stiffness
• Prognosis:
  • Symptoms improve in most cases with conservative treatment or surgery
  • Underlying conditions such as diabetes mellitus may be associated with a higher recurrence rate and a less favorable treatment response
• Precautions (including self-care)
  • Frequent use of repeated steroid injections increases the risk of tendon rupture → Consult a doctor about the interval and number of injections
  • Report immediately if skin changes or persistent pain occurs after an injection
  • Blood glucose control is important (for patients with diabetes)
  • After surgery, care for the wound and check for signs of infection (redness, warmth, discharge)

Outpatient Visit Checklist (Including Items to Bring and Sample Questions)

• Items to bring (recommended for the medical appointment)
  • All medications currently being taken (especially anticoagulants, antiplatelet agents, steroids, etc.)
  • Records of previous surgeries or injection treatments (related to the affected hand or finger)
  • Test results related to underlying conditions such as diabetes (recent blood glucose/HbA1c)
  • Symptom diary: onset, symptom frequency (when the finger catches), whether locking occurs, pain intensity, and occupational or repetitive work activities
• Main points the doctor will check during the outpatient visit
  • Which finger and which side (left/right), and whether one or multiple fingers are affected
  • Whether the finger cannot fully straighten (locked) or has intermittent catching/snapping
  • When symptoms are mainly worse (in the morning, during work, etc.)
  • Whether there has been any previous injection or surgery

Examples of General Questions to Ask the Doctor

• "What is the most appropriate initial treatment for these symptoms?"
• "What are the expected effects and side effects of a local steroid injection?"
• "When is surgery necessary, and what are the risks and complications of surgery?"
• "To what extent does my underlying condition (e.g., diabetes) affect the choice of treatment?"
• "What is the possibility of recurrence, and how should it be managed if it recurs?"

Examples of Condition-Specific Questions

• "This finger has already been bent for quite a long time (locked). Is it likely to straighten completely with surgery?"
• "I previously received a steroid injection, but its effect was temporary. Would you recommend surgery immediately instead of another injection? If I receive another injection, how many would be considered safe?"