2020 April Fools' Case: Normally we'd prank you with this but given the current COVID-19 crisis we decided just to release it straight up without trying to trick anyone. Hopefully you can at least still enjoy a little laugh at this difficult time - view case

Causes of sacroiliitis - symmetric vs asymmetric (mnemonic)

A mnemonic for remembering the symmetric vs asymmetric causes of sacroiliitis is:

  • PAIR


The outside letters P & R (letters are far apart) are the asymmetric causes and the inside letters A & I (letters are close together) are the symmetric causes. 

(This mnemonic was developed by Dr Joe Donahue)

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Article information

rID: 25174
Section: Mnemonics
Synonyms or Alternate Spellings:
  • PAIR (mnemonic)

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Cases and figures

  • Case 1: unilateral sacroilitis
    Drag here to reorder.
  • Case 2: bilateral sacroiliitis in AS
    Drag here to reorder.
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