Fig. 2A–D.

A 23-year-old man had a left proximal fibular simple (unicameral) bone cyst, which was nondiagnostic at core needle biopsy. Benign bone lesions had the lowest diagnostic yield (32%) in our study. (A) An AP radiograph shows a well-circumscribed lytic lesion in the proximal fibula (black arrow). A healing fracture is seen at the inferior margin of the lesion. The lesion (arrows) is low signal on the (B) axial T1-weighted and high signal on the (C) axial T2-weighted MR images. (D) A CT-guided core needle biopsy image shows a biopsy needle in the lesion.