Fig. 1. Proton density magnetic resonance imaging (MRI): the coronal (A) and sagittal (B) views showed a cartilage defect (arrows) on the right acetabulum. The defective cartilage lesion was also seen in computed tomography arthrography (CTA): coronal (C) and sagittal (D) views (arrows). Adjacent subchondral cyst of the acetabulum just above this chondral defect was observed in MRI and CTA. (E) Labral tear. (F) This lesion could be confirmed in arthroscopic examination after labral repair.