OsTrigonum Syndrome


  • Ostrigonum syndrome refers to pain in the back of the ankle. The Ostrigonum is an extra (accessory) bone that sometimes develops behind the ankle. The presence of an Ostrigonum in one or both feet is congenital (present at birth). It becomes evident during adolescence. Pain in the back of the ankle is the first indicator of Ostrigonum syndrome. The area in front of the Achilles tendon is sore to touch and the bony prominence may even be palpable. The diagnosis can usually be confirmed by x-ray views of the ankle from the side.

How did I get this?

  • Ostrigonum syndrome is usually triggered by an injury, such as an ankle sprain. The syndrome is also frequently caused by repeated downward pointing of the toes, which is common among ballet dancers, soccer players and other athletes.

What can I do about it?

  • Rest to stay off the injured foot to let the inflammation subside.
  • Applying a bag of ice covered with a thin towel to the affected area decreases inflammation process.
  • Short term nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, may be helpful in reducing the pain and inflammation.
  • Seek podiatry consultation.

What help can I get for this?

  • Podiatrist may consider immobilization using a walking boot or splint to restrict ankle motion to allow healing.
  • Your doctor may prescribe cortisone injection into the area to reduce the inflammation and pain.
  • Foot and ankle surgeon for possible removal of Ostrigonum.

When will it get better?

  • Most patients’ symptoms improve quickly with non-surgical treatment. However, in some patients, surgery may be required to relieve the symptoms. There is usually persistent swelling and discomfort after the surgery so limiting activities is required until these symptoms settle.