case_images: PMC9969429_01
case_images: X-ray (a) demonstrates a well-circumscribed osteolytic lesion involving the
  diaphysis of both the right radius and ulna with spiculated periosteal
  reaction. Ultrasonography images (b) show a heterogeneous intra-muscular
  mass, containing hypoechoic areas, and poorly vascularized on color
  Doppler.
case_images: 10.1177_2050313X231157485-fig1.jpg
case_images: PMC9969429_01_10.1177_2050313X231157485-fig1.jpg
case_images: fig1-2050313X231157485
case_images: X-ray examination exhibited a soft-tissue mass encompassing the two bones of the forearm in a circumferential way, with well-defined margins, associated with medullary bone lysis, a significant discontinuous spiculated periosteal reaction, and a deformation of the bones' axes (Figure 1(a)). Ultrasound showed a heterogeneous poorly vascularized mass (Figure 1(b)).
case_images: A 12-year-old young girl with infantile fibromatosis in the right forearm.
  (a) Coronal T2WI demonstrates a lobulated, heterogeneous hyperintense mass
  with irregular strip hypo intensities (arrows). (b) On coronal T1WI, the
  mass is homogeneous and isointense, with medullar bone lesion presenting the
  same characteristics. (c) The lesion is hyperintense on diffusion. (d) On
  contrast-enhanced axial FS T1WI, the lesion shows inhomogeneous marked
  enhancement with non-enhanced hypointense fibrous areas.
case_images: 10.1177_2050313X231157485-fig2.jpg
case_images: PMC9969429_01_10.1177_2050313X231157485-fig2.jpg
case_images: fig2-2050313X231157485