case_images: PMC9563229_01
case_images: Knee radiograph showing a lytic lesion in the femur with lamellated periosteal reaction.
case_images: jbsr-106-1-2893-g1.jpg
case_images: PMC9563229_01_jbsr-106-1-2893-g1.jpg
case_images: F1
case_images: The patient underwent a knee radiograph that showed a lytic bone lesion in the femur (asterisk in Figure 1) with lamellated periosteal reaction (arrows in Figure 1).
case_images: CT of the knee showing preserved integrity of the femur's cortex.
case_images: jbsr-106-1-2893-g2.jpg
case_images: PMC9563229_01_jbsr-106-1-2893-g2.jpg
case_images: F2
case_images: Computed tomography (CT) of the knee showed loss of the normal trabeculation of the femur's medulla (asterisk in Figure 2A), with preserved integrity of the cortex. Periosteal reaction (arrow in Figure 2A) and densification of the adjacent soft tissues (arrowhead in Figure 2B) were noticed.
case_images: MRI of the knee showing a large soft tissue mass infiltrating the thigh's muscles.
case_images: jbsr-106-1-2893-g3.jpg
case_images: PMC9563229_01_jbsr-106-1-2893-g3.jpg
case_images: F3
case_images: Magnetic resonance imaging (MRI) revealed a large soft tissue mass infiltrating the thigh's muscles (arrows in Figure 3) and the neuro-vascular bundle (arrowheads in Figure 3C and 3D). T1-weighted images (T1WI) (Figure 3A and 3C), high signal on DP-weighted images with fat saturation (FS DPWI) (Figure 3B) and enhanced after contrast injection (Figure 3D). The medulla of the femur was hypointense on T1WI (asterisk in Figure 3A) and hyperintense on FS DPWI (asterisk in Figure 3B). There was no cortical disruption.