What is the recommended approach to evaluate and treat trigger finger?

Evaluation and Treatment of Trigger Finger

Diagnosis

Trigger finger should be treated initially with conservative measures including activity modification, splinting, and corticosteroid injections, progressing to surgical release only if these measures fail. 1

Trigger finger (stenosing flexor tenosynovitis) is characterized by:

• Pain, clicking, catching, and loss of motion of the affected finger
• Inflammation and narrowing of the A1 pulley causing impaired movement of the flexor tendon
• Higher prevalence in diabetic patients and women in their 50s-60s 1

Clinical Evaluation

• Look for:
  • Clicking or locking of the finger during flexion/extension
  • Palpable nodule at the base of the finger (over the metacarpophalangeal joint)
  • Pain over the A1 pulley
  • Finger catching in flexion requiring passive extension
  • Morning stiffness of the affected digit

Diagnostic Imaging

• Radiographs are not routinely needed but may be considered to rule out other pathologies 2
• Ultrasound can be useful for:
  • Confirming diagnosis in unclear cases
  • Visualizing tendon thickening and A1 pulley changes
  • Guiding therapeutic injections 3

Treatment Algorithm

First-Line Treatment

1. Activity Modification

   • Avoid repetitive gripping or activities that exacerbate symptoms
   • Joint protection techniques to minimize stress on affected fingers 3

2. Splinting

   • Custom-made neoprene or rigid rest orthosis worn at night 2
   • Splint should keep the metacarpophalangeal joint in slight flexion to prevent triggering
   • Consider orthoses for first carpometacarpal joint involvement 3

3. Pain Management

   • Topical NSAIDs as first-line analgesic 3
   • Oral paracetamol for mild to moderate pain as second-line 3
   • Oral NSAIDs as third-line, though evidence specifically for trigger finger is limited 4

Second-Line Treatment

Corticosteroid Injections

• Highly effective treatment with approximately 60-90% success rate after a single injection 5, 6
• Technique:
  • Inject corticosteroid (typically triamcinolone 20mg or methylprednisolone) with lidocaine into the flexor tendon sheath
  • Number needed to treat is 3 compared to lidocaine alone 6
• Recurrent episodes (27%) can be effectively re-treated with additional injections 5
• Potential side effects include:
  • Pain at injection site
  • Skin depigmentation
  • Subcutaneous fat atrophy
  • Tendon rupture (rare)

Third-Line Treatment

Surgical Release

• Indicated when:
  • Conservative treatments fail (approximately 12% of cases) 5
  • Recurrent symptoms despite multiple injections
  • Fixed deformity or severe locking
• Surgical options:
  • Open A1 pulley release (most common)
  • Percutaneous A1 pulley release
  • Excision of a slip of the flexor digitorum superficialis (for persistent triggering) 7

Special Considerations

Pediatric Trigger Finger/Thumb

• Pediatric trigger thumb is treated with open A1 pulley release
• Pediatric trigger finger may require release of A1 pulley with possible excision of flexor digitorum superficialis if triggering persists 7

Diabetic Patients

• Higher incidence and often multiple digits involved
• May have lower success rates with corticosteroid injections
• May require earlier consideration of surgical intervention

Post-Treatment Rehabilitation

• Active finger motion exercises to maintain mobility 2
• Strengthening exercises to stabilize the joint 3
• Follow-up in 4-6 weeks to evaluate response to treatment 3

Prognosis

• Approximately 80% of patients recover fully within 3-6 months with appropriate treatment 2
• Success rates with corticosteroid injections approach 90% 5
• Surgical release has high success rates (>90%) when indicated

Trigger finger is a common condition that responds well to a stepwise treatment approach. While most cases resolve with conservative management, timely progression to more invasive treatments is appropriate when symptoms persist to prevent permanent contractures and functional impairment.