Codman triangle periosteal reaction

A 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 after the American surgeon Ernest Amory Codman (1869-1940), who described it in the setting of Ewing sarcoma 3,4.

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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