Pyknodysostosis

  • Etiology: congenital
  • Imaging: generalized osteosclerosis, short stature, short broad hands, frequent fractures, Wormian bones
  • DDX: differentiate from osteopetrosis by absence of bone in bone
  • Clinical: acromelic skeletal dysplasia

Radiology Cases of Pyknodysostosis

CT and skull radiographs of pyknodysostosis
AP and lateral radiographs of the skull (above) and axial CT without contrast of the brain (below) shows diffusely sclerotic skull bones with a thickened diploic space and diastatis of the coronal and lambdoid and sagittal sutures.
Lower extremity radiograph of pyknodysostosis
AP radiographs of the lower extremities shows generalized osteosclerosis of the bones without a bone in bone appearance.