Send to

Choose Destination
Ann Rheum Dis. 2015 Jun;74(6):985-92. doi: 10.1136/annrheumdis-2013-203887. Epub 2014 Jan 22.

Does spinal MRI add incremental diagnostic value to MRI of the sacroiliac joints alone in patients with non-radiographic axial spondyloarthritis?

Author information

Department of Medicine, University of Alberta, Edmonton, Alberta, Canada Department of Rheumatology, Balgrist University Hospital, Zurich, Switzerland.
Department of Radiology, Balgrist University Hospital, Zurich, Switzerland.
Department of Rheumatology, PLA General Hospital, Beijing, China.
Department of Radiology and Diagnostic Imaging, University of Alberta, Edmonton, Alberta, Canada.
Department of Ophthalmology, University of Alberta, Edmonton, Alberta, Canada.
Copenhagen Center for Arthritis Research, Center for Rheumatology and Spinal Diseases, University of Copenhagen, Copenhagen, Denmark.
Rufibach rePROstat, Biostatistical Consulting and Training, Basel, Switzerland.
Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.



To assess the incremental diagnostic value of spine MRI evaluated separately from and combined with sacroiliac joint (SIJ) MRI in non-radiographic axial spondyloarthritis (nr-axSpA) compared with SIJ MRI alone.


The study sample comprised two independent cohorts A/B of 130 consecutive patients aged ≤50 years with back pain, newly referred to two university clinics, and 20 healthy controls. Patients were classified according to clinical examination and pelvic radiographs as having nr-axSpA (n=50), ankylosing spondylitis (n=33), or non-specific back pain (n=47). Four readers assessed SIJ and spine MRI separately 6 months apart, and 1-12 months later both scans simultaneously using standardised modules. Readers recorded presence/absence of SpA and their level of confidence in this conclusion on a 0-10 scale (0=definitely not; 10=definite). We analysed differences between SIJ MRI versus spine MRI alone, and SIJ MRI alone versus combined MRI, descriptively by the number/percentage of subjects according to the mean of four readers.


In cohorts A/B, 15.8%/24.2% of patients with nr-axSpA having a negative SIJ MRI were reclassified as being positive for SpA by global evaluation of combined scans. However, 26.8%/11.4% of non-specific back pain controls and 17.5% of healthy volunteers with a negative SIJ MRI were falsely reclassified as having SpA by combined MRI. Low confidence in a diagnosis of SpA by SIJ MRI increased to high confidence by combined MRI in 6.6%/7.3% of patients with nr-axSpA.


Combined spine and SIJ MRI added little incremental value compared with SIJ MRI alone for diagnosing patients with nr-axSpA and enhancing confidence in this diagnosis.


Ankylosing Spondylitis; Magnetic Resonance Imaging; Spondyloarthritis

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center