{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T02:30:46Z","timestamp":1786415446155,"version":"build-2736575974"},"reference-count":43,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T00:00:00Z","timestamp":1782432000000},"content-version":"vor","delay-in-days":176,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Rheumatology and Radiology Departments at the Clinical Hospital of the University of Chile"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,6,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To evaluate the diagnostic performance of MRI-defined sacroiliitis for axial spondyloarthritis (axSpA) in routine clinical practice and to characterize inflammatory spinal lesions (ISLs) and clinical factors associated with sacroiliitis across non-psoriatic axSpA (nPsA-axSpA), axial psoriatic arthritis (axPsA) and non-inflammatory chronic back pain (NI-CBP).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective study of adults with chronic back pain who underwent SI joint and whole-spine MRI for suspected axSpA. Following longitudinal follow-up, patients were classified by expert rheumatologists as nPsA-axSpA, axPsA or NI-CBP. Two blinded musculoskeletal radiologists independently assessed MRI scans for sacroiliitis and ISLs using Assessment of SpondyloArthritis international Society\/OMERACT definitions. Diagnostic accuracy metrics for MRI-defined sacroiliitis were calculated using expert diagnosis as the reference standard and multivariate logistic regression was used to identify predictors of sacroiliitis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Ninety-five patients were included (29 nPsA-axSpA, 21 axPsA, 45 NI-CBP). MRI-defined sacroiliitis showed high specificity (91%) and moderate sensitivity (77\u201383%) for axSpA diagnosis. Independent predictors of sacroiliitis included age [odds ratio (OR) 1.05\/year], regular physical activity (OR 3.50), expert-assessed inflammatory back pain (OR 35.11) and the number of SpA features (OR 1.72). ISLs were present in 40% of patients overall and were most prevalent in axPsA (76%). In axPsA, ISLs frequently occurred in the absence of sacroiliitis and displayed a broader and more heterogeneous distribution.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>MRI-defined sacroiliitis is highly specific but insufficient as a stand-alone diagnostic tool for axSpA in real-world settings and should be interpreted in context.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/rap\/rkag072","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T11:50:38Z","timestamp":1782301838000},"source":"Crossref","is-referenced-by-count":0,"title":["MRI-defined sacroiliitis and spinal inflammation in chronic back pain: real-world patterns in axial spondyloarthritis and axial psoriatic arthritis"],"prefix":"10.1093","volume":"10","author":[{"given":"Mauricio","family":"Parada","sequence":"first","affiliation":[{"name":"Rheumatology, Hospital Cl\u00ednico de la Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda L","family":"Molina","sequence":"additional","affiliation":[{"name":"Rheumatology, Hospital Cl\u00ednico de la Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"R\u00edos","sequence":"additional","affiliation":[{"name":"Radiology, Hospital Cl\u00ednico de la Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniela","family":"Su\u00e1rez","sequence":"additional","affiliation":[{"name":"Radiology, Hospital Cl\u00ednico de la Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mauricio","family":"Ochoa","sequence":"additional","affiliation":[{"name":"Internal Medicine, Hospital del Trabajador , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natalie","family":"Hitchin","sequence":"additional","affiliation":[{"name":"Medicine, Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Crist\u00f3bal","family":"Bravo","sequence":"additional","affiliation":[{"name":"Medicine, Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicol\u00e1s","family":"Guzm\u00e1n","sequence":"additional","affiliation":[{"name":"Medicine, Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pablo","family":"Barahona","sequence":"additional","affiliation":[{"name":"Medicine, Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6832-3728","authenticated-orcid":false,"given":"Annelise","family":"Goecke","sequence":"additional","affiliation":[{"name":"Rheumatology, Hospital Cl\u00ednico de la Universidad de Chile , Santiago,","place":["Chile"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,6,26]]},"reference":[{"key":"2026081022070122000_rkag072-B1","doi-asserted-by":"publisher","first-page":"777","DOI":"10.1136\/ard.2009.108233","article-title":"The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part II): validation and final selection","volume":"68","author":"Rudwaleit","year":"2009","journal-title":"Ann Rheum 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