Codman triangle periosteal reaction

Codman triangle is a type of periosteal reaction seen with aggressive bone lesions. The periosteum does not have time to ossify with shells of new bone (e.g. as seen in a single layer and multilayered periosteal reaction) in aggressive lesions, so only the edge of the raised periosteum will ossify.

The Codman triangle may be seen with the following aggressive lesions:

History and etymology

It was first described by Ribbert in 1914 2. However, it is named for Ernest Amory Codman, who described it in the setting of Ewing sarcoma 3.

See also

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Article information

rID: 1142
Section: Gamuts, Signs
Tag: refs
Synonyms or Alternate Spellings:
  • Codman's triangle
  • Codman's triangles
  • Codman triangles

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Cases and figures

  • Figure 1: types of periosteal reactions
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  • Case 1: Codman triangle
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    Case 2: Codman triangle
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  • Case 3
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  • Case 4
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  • Case 5
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