Fig. 8

Differential diagnosis of os fibulare. a AP radiograph in a 67-year-old woman, history of inversion injury. There is a small avulsion of the tip of the malleolus, in keeping with injury to the lateral collateral ligament (arrow head). Medial to this, there is a small ossified body (black arrow). This has rounded margins. Findings are compared with previous MR, performed 10 years before. b Coronal FSE T1 demonstrates a small ossified body was present already (white arrow). MR was performed with the suspicion of talonavicular osteoarthritis at the time. A small rounded structure could have already represented a sequel of avulsion injury but was described as an ossicle in the absence of acute trauma