The trigger finger is classified according to the severity of the symptoms:

1. Grade 1: Pain and stiffness, without visible "snapping."
2. Grade 2: Noticeable "snapping" of the finger during movement, but without locking.
3. Grade 3: Locking of the finger in a bent or extended position, which can be actively overcome.
4. Grade 4: Permanent fixation of the finger in a bent or extended position, which cannot be resolved either actively or passively.

The main causes of trigger finger are mechanical, inflammatory, and systemic factors:

• Mechanical stress:
  • Repeated movements, as seen in manual work or playing musical instruments.
  • Overuse of the fingers due to sports or heavy physical labor.
• Inflammatory changes:
  • Thickening of the tendon sheaths due to local inflammation, often as a result of microtraumas.
• Systemic diseases:
  • Rheumatoid arthritis, gout, or diabetes mellitus, which can affect the tendon gliding tissue.
• Anatomical factors:
  • Congenital narrowings in the tendon system or acquired changes, such as scarring.

The symptoms vary depending on the severity and progression of the disease, but typically include:

• Pain: Localized pain at the base of the finger, especially with pressure or movement.
• “Triggering” of the finger: Jerky bending or straightening, often accompanied by a palpable resistance.
• Stiffness: Noticeable movement restrictions, especially in the morning.
• Swelling: In the area of the affected tendon, often palpable.
• Locking: The finger remains fixed in a bent or straight position and can only be moved with difficulty.
• Tenderness: Pressure pain at the insertion of the affected tendon.

The diagnosis is based on medical history, clinical examination, and, if necessary, imaging techniques:

• Medical history:
  • The doctor inquires about the duration and intensity of the symptoms as well as possible strenuous activities.
• Physical examination:
  • Palpation of the affected tendon to detect swelling or thickening.
  • Observation of the "snapping" and mobility of the finger.
• Imaging:
  • Ultrasound: Visualization of tendon thickening or narrowing of the tendon sheath.
  • MRI: In rare cases, required for the assessment of soft tissue structures. 

Conservative Therapy

In the early stages, non-operative treatment is often sufficient:

• Immobilization: Avoidance of strenuous activities and use of splints or bandages.
• Medication Therapy:
  • NSAIDs: For pain relief and anti-inflammatory effects.
  • Injections of corticosteroids into the affected tendon sheath to reduce inflammation.
• Physiotherapy:
  • Mobilization of the fingers through targeted exercises to improve mobility.
  • Manual therapy to release adhesions.
• Local Applications:
  • Cold therapy to reduce acute inflammation.
  • Heat applications for chronic complaints.

Surgical Therapy

In cases of persistent complaints or blockages, surgery is necessary:

• Annular Ligament Release: Surgical widening of the affected tendon sheath to restore mobility.
• Minimally Invasive Techniques: Gentle procedures with a short rehabilitation period.
• Reconstruction: In rare cases of severe scarring or anatomical anomalies.

To prevent trigger finger and support recovery, the following measures are recommended:

1. Ergonomic hand movements: Avoid excessive strain through optimized workflows.
2. Regular breaks: Relieve the hands during prolonged activities.
3. Muscle strengthening: Strengthen the hand and finger flexors through targeted training.
4. Early detection: Seek medical help promptly at the first signs of pain or stiffness.
5. Adjustment of work tools: Use ergonomic tools to reduce strain.