Figure 5d: (a) AP and (b) lateral radiographs and (c) coronal and (d) sagittal T1-weighted spin-echo (340/15) MR images of the left knee in a 45-year-old man. Epiphysis involvement is clearly depicted as an area of low signal intensity on the MR images. Areas of fatty marrow are preserved in the subchondral bone and metaphyses (arrows).