Rim sign (avascular necrosis)

A rim sign can be seen in avascular necrosis and comprises a high T2 or intermediate T1 signal line sandwiched between two low signal lines, and represents fluid between the sclerotic borders of an osteochondral fragment, and implies instability (stage III).

This rim sign should not be confused with the double line sign of osteonecrosis/AVN.

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Article information

rID: 1987
Section: Signs
Tag: knee
Synonyms or Alternate Spellings:
  • Rim sign (AVN)
  • Rim sign of AVN

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Cases and figures

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