Published: 2020-12-23

A fracture of OS trigonum: a rare case report

Gnanaprakash Palaniappan, Chetan John Rasquinha, Major K. Kamalanathan


Fractures of os trigonum is an extremely rare event. It is one of the accessory ossicles of the foot found in about 7 % of the population. Very few cases have been reported in the literature about a fracture of the ostrigonum. We present a case of fracture of ostrigonum with associated fracture of the fibula and a large lacerated wound in the leg, in a young man sustained due to road traffic accident. The initial radiological examination with Xray ankle showed a doubtful fracture of posterior process of talus but was not clear. The diagnosis was clinched by CT scan of the ankle with 2mm cuts, which showed clearly a fracture of the os trigonum. It was treated by flap cover for the wound and plaster immobilisation for the fracture. So, any doubtful fracture near the posterior process of talus should be fully assessed radiologically with a CT scan to guide in the treatment.


OS trigonum, Talus, Posterior process, Fracture

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