Os Trigonum

An os trigonum is a small accessory bone located behind the ankle joint that can cause posterior ankle pain when compressed during motion. It often contributes to posterior impingement, especially in ballet dancers and soccer players.

Anterior Ankle Impingement

    • Deep posterior ankle pain with pointing the toes

    • Swelling or tenderness behind the ankle

    • Painful plantarflexion during sports or dance

  • X-ray or MRI confirms the presence of an os trigonum and rules out other causes of pain.

  • Non-surgical management includes rest and physical therapy. Persistent pain may require arthroscopic excision of the os trigonum for symptom relief.

  • Full recovery is expected within 6–10 weeks post-surgery, with early return to low-impact activities.