Clinical assessment of sacroiliitis and HLA-B27 are poor predictors of sacroiliitis diagnosed by magnetic resonance imaging in psoriatic arthritis

Rheumatology (Oxford). 2004 Jan;43(1):85-8. doi: 10.1093/rheumatology/keg475. Epub 2003 Sep 16.


Objective: To determine the frequency and clinical predictors of sacroiliitis diagnosed by magnetic resonance imaging (MRI) in a psoriatic arthritis (PsA) population.

Methods: The studied comprised 103 patients with PsA. A careful clinical assessment for sacroiliitis was made from history and examination, and HLA-B27 testing was performed. Sixty-eight patients underwent tilted coronal fat-saturated T1-weighted and STIR MRI of the sacroiliac joints.

Results: Clinical features of moderate or severe sacroiliitis were found in 24/68 (35%) patients. MRI features of sacroiliitis were found in 26/68 (38%) patients. Clinical features of sacroiliitis were present in 14/42 (33%) with normal MRI scans and 10/26 (38%) with abnormal scans (normal vs abnormal scans, P = 0.7). The presence of sacroiliitis on MRI was associated with restricted spinal movements (P = 0.004) and the duration of PsA (P = 0.04). There was no correlation between HLA-B27 and sacroiliitis diagnosed by MRI.

Conclusion: Sacroiliitis diagnosed by MRI occurs commonly in PsA but is difficult to detect clinically.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Arthritis, Psoriatic / diagnosis*
  • Arthritis, Psoriatic / immunology
  • Female
  • HLA-B27 Antigen / analysis*
  • Humans
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Prevalence
  • Sacroiliac Joint / pathology*


  • HLA-B27 Antigen