Radiopaedia 2021 UPDATE Conference-only registration is now closed. Late registration for All-Access Pass and Free Country Pass holders has been extended until Friday 30 July - LEARN MORE


Exostoses are defined as benign growths of bone extending outwards from the surface of a bone. It can occur in any bone and be triggered by a number of factors. There are a number of examples of exostoses that occur due to local irritant stimuli:

Where exostoses are capped with cartilage, they are termed osteochondromas, which can be solitary or multiple, sessile or pedunculated:

Bone tumours

The differential diagnosis for bone tumors is dependent on the age of the patient, with a very different set of differentials for the pediatric patient.

Article information

rID: 17041
Section: Gamuts
Tag: refs
Synonyms or Alternate Spellings:
  • Exostoses

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1: subungual exostosis
    Drag here to reorder.
  • Case 2: surfer's ear
    Drag here to reorder.
  • Case 3: pedunculated exostosis
    Drag here to reorder.
  • Case 4: sessile exostosis - humerus
    Drag here to reorder.
  • Case 5: sessile exostosis - tibia
    Drag here to reorder.
  • Case 6: spinous process of the C2
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.