The sinus tarsi syndrome is classified according to cause and severity:

1. By cause:
   • Traumatic: Triggered by injuries such as twisting or ligament tears.
   • Degenerative: Caused by chronic overuse or instability of the ankle joint.
   • Inflammatory: Due to inflammatory diseases such as arthritis or gout.
2. By severity:
   • Acute: Sudden onset of symptoms after an injury.
   • Chronic: Long-lasting or recurring symptoms without a clear trigger.

The causes of sinus tarsi syndrome can be divided into traumatic, mechanical, and inflammatory factors:

- Traumatic causes:

- Sprains or ligament tears in the ankle joint leading to instability.

- Injuries from twisting the foot, often in sports like soccer or basketball.

- Mechanical causes:

- Chronic instability of the ankle joint due to weak ligaments or muscles.

- Misalignments such as flatfoot, which increase the load on the sinus tarsi.

- Inflammatory causes:

- Arthritis or rheumatic diseases affecting the sinus tarsi.

- Gout or pseudogout, where crystals deposit in the affected region.

The symptoms of sinus tarsi syndrome are often characteristic and include:

• Localized pain: Pain in the area of the sinus tarsi, often intensified with stress or pressure.
• Swelling: Slight swelling around the ankle or heel.
• Feeling of instability: Uncertainty or giving way of the ankle joint, especially when walking on uneven surfaces.
• Movement restrictions: Pain during certain movements, especially during rotational movements of the foot.
• Tenderness: Pain when touching or pressing on the sinus tarsi.

The diagnosis is made through a combination of medical history, clinical examination, and imaging techniques:

• Medical History:
  • Collection of medical history, possible injuries, or chronic overuse.
• Physical Examination:
  • Pressure test on the sinus tarsi to check for tenderness.
  • Stability tests of the ankle joint to assess for instabilities.
• Imaging:
  • MRI: Visualization of inflammation, fluid accumulation, or ligament injuries.
  • X-ray: To rule out fractures or bony changes.
  • Ultrasound: Detection of fluid or swelling in the area.

Conservative Therapy

In most cases, sinus tarsi syndrome can be successfully treated without surgical intervention:

• Immobilization: Relief of the ankle joint using bandages, splints, or orthoses.
• Medication Therapy:
  • NSAIDs: For pain relief and anti-inflammatory effects.
  • Corticosteroid injections for severe inflammation.
• Physiotherapy:
  • Exercises to stabilize and strengthen the ankle joint muscles.
  • Manual therapy to improve mobility.
• Local Applications:
  • Cold therapy for acute discomfort to relieve pain.
  • Heat treatment for chronic pain to promote blood circulation.

Surgical Therapy

In cases of persistent discomfort or chronic instability, surgery may be necessary:

• Arthroscopic Debridement: Removal of inflamed tissue or fluid accumulations.
• Ligament Reconstruction: Stabilization of the ankle joint by restoring or reinforcing the ligaments.
• Correction of Misalignments: Treatment of underlying orthopedic issues, such as flatfoot.

To prevent sinus tarsi syndrome and minimize the risk of recurrence, the following measures are suitable:

1. Strengthening of the ankle joint muscles: Regular training to stabilize the joint.
2. Avoidance of overloading: Adjustment of sports activities and loads.
3. Ergonomic footwear: Use of shoes with good cushioning and stability.
4. Rehabilitation after injuries: Consistently performed physiotherapy to avoid instabilities.
5. Regular check-ups: Early detection and treatment of misalignments or inflammations.