Tarsal tunnel syndrome is classified according to cause and severity:

1. By cause:
   • Mechanical: Due to overuse, foot deformities, or scar formation.
   • Traumatic: After fractures, dislocations, or other injuries in the ankle area.
   • Systemic: In diseases such as diabetes, rheumatism, or gout.
   • Space-occupying: Due to tumors, ganglia, or cysts in the tarsal tunnel.
2. By severity:
   • Mild: Intermittent symptoms that are alleviated by rest periods.
   • Moderate: Frequent symptoms with beginning motor limitations.
   • Severe: Persistent pain, numbness, and weakness of the foot muscles.
3. By location:

• Anterior tarsal tunnel syndrome
  • Affects the N. fibularis profundus (deep fibular nerve).
  • Cause: Pressure or irritation in the area of the extensor retinaculum on the dorsum of the foot (e.g., due to tight shoes, swelling, injuries).
  • Symptoms: Burning pain and numbness in the area of the toe spaces (especially between the 1st and 2nd toe).

• Posterior tarsal tunnel syndrome

  • Affects the N. tibialis in the tarsal tunnel (behind the medial malleolus).
  • Cause: Narrowing due to swelling, inflammation, varicose veins, scar formation, or deformities (e.g., flatfoot).
  • Symptoms: Pain, tingling, and numbness on the sole of the foot and toes, often worsened when walking or after exertion.

The causes of tarsal tunnel syndrome can be mechanical, systemic, or traumatic:

• Mechanical causes:
  • Foot deformities such as flatfoot or high arch, which increase pressure in the tarsal tunnel.
  • Scar tissue or thickening of ligaments that constrict the nerve.
  • Repeated stress from sports activities or standing work.
• Traumatic causes:
  • Fractures or dislocations in the ankle area that narrow the tarsal tunnel.
• Systemic causes:
  • Diabetes mellitus, which increases nerve sensitivity and delays healing.
  • Rheumatoid arthritis or gout, which can lead to inflammation in the tarsal tunnel.
• Space-occupying processes:
  • Ganglia, tumors, or vascular anomalies that exert pressure on the tibial nerve.

The symptoms depend on the severity of the compression and include:

- **Pain:** Burning or stabbing pain on the inside of the ankle or the arch of the foot, often radiating to the toes.

- **Paresthesia:** Tingling, numbness, or a feeling of "pins and needles" in the foot.

- **Weakness:** Reduced strength in the foot muscles, especially during prolonged walking or standing.

- **Swelling:** Visible or palpable swelling in the area of the tarsal tunnel during inflammatory processes.

- **Worsening with exertion:** Symptoms worsen with activity and improve at rest.

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

• Medical history:
  • Collection of symptoms, stress patterns, and possible injuries or underlying diseases.
• Physical examination:
  • Palpation of the tarsal tunnel for tenderness.
  • Provocation tests such as the Tinel test, where tapping on the tarsal tunnel triggers symptoms.
• Imaging:
  • Ultrasound: Visualization of thickenings or masses in the tarsal tunnel.
  • MRI: For assessing soft tissues, ligaments, and nerves.
  • X-ray: To rule out bony changes or fractures.
• Electrophysiological studies:
  • Measurement of nerve conduction velocity (NCV) to demonstrate slowing due to compression.

Conservative Therapy

Treatment usually begins with conservative measures:

• Relief of the nerve:
  • Avoidance of strains or movements that exacerbate the symptoms.
  • Use of insoles or orthopedic shoes to correct misalignments.
• Physiotherapy:
  • Mobilization exercises to improve mobility.
  • Stretching exercises for the surrounding muscles.
• Medication therapy:
  • NSAIDs: For pain relief and anti-inflammatory effects.
  • Local injections of corticosteroids to reduce inflammation.
• Cold therapy: To alleviate swelling and pain in acute conditions.

Surgical Therapy

If conservative measures are not sufficient, surgery may be necessary:

• Decompression: Exposure and relief of the tibial nerve by removing tissue or space-occupying lesions.
• Reconstruction: Treatment of structural problems such as ligament thickening or bone misalignments.
• Post-treatment: Physiotherapy to restore mobility and function. 

To prevent and reduce the risk of recurrence, the following measures are suitable:

1. Ergonomic footwear: Use of well-fitting shoes with sufficient cushioning and support.
2. Correction of misalignments: Use of orthopedic aids to relieve the tarsal tunnel.
3. Regular exercise: Promotion of blood circulation and flexibility through moderate physical activity.
4. Avoidance of overstrain: Adjusted loads and breaks during sports activities or standing tasks.
5. Early detection: Early medical examination at the first symptoms to prevent worsening.