Polyostotic Fibrous Dysplasia

  • Etiology: Focal arrest in normal osteoblastic activity resulting in presence of all components of normal bone with lack of normal differentiation into their mature structures
  • Imaging: Lucent or ground glass lesion in marrow with sclerotic rim that is multifocal and unilateral
  • DDX:
  • Complications:
  • Treatment:
  • Clinical:
    — 20% of fibrous dysplasia is polyostotic
    — McCune-Albright syndrome (2% of fibrous dysplasia) is polyostotic fibrous dysplasia and precocious puberty and cafe au-lait spots

Radiology Cases of Polyostotic Fibrous Dysplasia

Radiograph of polyostotic fibrous dysplasia
AP radiograph of the femur (above left) shows a metaphyseal lesion that is expansile, lytic in appearance, with a narrow zone of transition and no periosteal new bone that has the appearance of a shepherd’s crook. AP radiograph of the bilateral tibia and fibula (upper right) shows multiple left tibial metaphyseal and diaphyseal lesions that are lytic in appearance with a narrow zone of transition and no periosteal reaction. AP radiograph of the feet (below) shows lesions in the diaphysis of the left first metatarsal and proximal phalanx that are lytic in appearance with a narrow zone of transition and no periosteal new bone.
Radiograph of polyostotic fibrous dysplasia
AP radiograph of the humerus (left) shows a lengthy ground glass lesion with a sclerotic rim centered in the metaphysis of the humerus. AP radiograph of the hand (right) shows multiple lucent lesions with sclerotic rims in the capitate and hamate and in the proximal fourth and fifth metacarpal bones.