Involvement of the proximal tibial epiphysis by monostotic fibrous dysplasia

We report a case of monostotic fibrous dysplasia (FD) solely demonstrating epiphyseal lesion. A 13-year-old boy was referred to our hospital complaining of pain in his left knee joint. Plain radiographs showed an osteolytic lesion with slightly sclerotic margin at the proximal epiphysis of the left tibia. The lesion was shown with low intensity on T1-weighted and high on T2*-weighted magnetic resonance imaging. Contrast-enhanced T1-weighted images showed marginal enhancement of the lesion. Histological examination of the surgical specimens showed FD.