Infantile Cortical Hyperostosis

  • Etiology: Unknown
  • Imaging Radiograph:
    — Asymmetrical cortical thickening and marrow fibrosis
    — Most commonly affects flat bones in early infancy – mandible (80%) or clavicle or ribs or scapula or skull or ilium
    — Asymmetrical involvement of ulnar diaphysis most common pattern of tubular bone involvement
  • DDX:
  • Complications:
  • Treatment:
  • Clinical:
    — Presents before 9 weeks old and unusual after 6 months old
    — Usually spontaneously resolves in 6-9 months
    — Can have irritability and acute pain and soft tissue swelling and elevated alkaline phosphatase

Radiology Cases of Infantile Cortical Hyperostosis

CXR of infantile cortical hyperostosis
CXR AP (above) shows marked cortical thickening of all of the left ribs and the lower right ribs and the left humerus. CXR AP taken one year later (below) shows complete resolution of the cortical thickening.
Radiograph of infantile cortical hyperostosis of clavicle
CXR AP shows marked periosteal reaction involving the left clavicle which is thickened and hyperostotic in appearance. The right clavicle is normal.