R. 1. Haibel, H. Rudwaleit, M. Sieper, and J. , Outcome parameters in ankylosing spondylitis]. Z Für Rheumatol, pp.131-135, 2006.

A. Lacout, B. Rousselin, and J. Pelage, CT and MRI of Spine and Sacroiliac Involvement in Spondyloarthropathy, American Journal of Roentgenology, vol.191, issue.4, pp.1016-1039, 2008.
DOI : 10.2214/AJR.07.3446

M. Rudwaleit, A. Jurik, K. Hermann, R. Landewé, D. Van-der-heijde et al., Defining active sacroiliitis on magnetic resonance imaging (MRI) for classification of axial spondyloarthritis: a consensual approach by the ASAS/OMERACT MRI group, Annals of the Rheumatic Diseases, vol.68, issue.10, pp.1520-1527, 2009.
DOI : 10.1136/ard.2009.110767

J. Braun and J. Sieper, Ankylosing spondylitis. Lancet, pp.1379-90, 2007.
URL : https://hal.archives-ouvertes.fr/hal-00503871

L. Jans, C. Van-langenhove, V. Praet, L. Carron, P. Elewaut et al., Diagnostic value of pelvic enthesitis on MRI of the sacroiliac joints in spondyloarthritis, European Radiology, vol.72, issue.4
DOI : 10.1136/annrheumdis-2012-201545

R. Carmona, S. Harish, D. Linda, G. Ioannidis, M. Matsos et al., MR Imaging of the Spine and Sacroiliac Joints for Spondyloarthritis: Influence on Clinical Diagnostic Confidence and Patient Management, Radiology, vol.269, issue.1, pp.208-223, 2013.
DOI : 10.1148/radiol.13121675

C. Giraudo, S. Magnaldi, M. Weber, A. Puchner, H. Platzgummer et al., Optimizing the MRI protocol of the sacroiliac joints in Spondyloarthritis: which para-axial sequence should be used?, European Radiology, vol.37, issue.1, 2015.
DOI : 10.3899/jrheum.090519

T. Dietrich, E. Ulbrich, M. Zanetti, S. Fucentese, and C. Pfirrmann, PROPELLER Technique to Improve Image Quality of MRI of the Shoulder, American Journal of Roentgenology, vol.197, issue.6, pp.1093-100, 2011.
DOI : 10.2214/AJR.10.6065

L. Carucci, Imaging obese patients: problems and solutions. Abdom Imaging, 2013.
DOI : 10.1007/s00261-012-9959-2

R. Uppot, D. Sahani, P. Hahn, D. Gervais, and P. Mueller, Impact of Obesity on Medical Imaging and Image-Guided Intervention, American Journal of Roentgenology, vol.188, issue.2, pp.433-473, 2007.
DOI : 10.2214/AJR.06.0409

K. Fujimoto, T. Koyama, K. Tamai, N. Morisawa, T. Okada et al., BLADE acquisition method improves T2-weighted MR images of the female pelvis compared with a standard fast spin-echo sequence, European Journal of Radiology, vol.80, issue.3, pp.796-801, 2011.
DOI : 10.1016/j.ejrad.2010.08.002

C. Ng and C. Palmer, Assessing Diagnostic Confidence, Academic Radiology, vol.15, issue.5, pp.584-92, 2008.
DOI : 10.1016/j.acra.2007.12.004

S. Rubin, S. Totterman, S. Meyers, and D. Hartley, Magnetic resonance imaging of the hip with a pelvic phased-array surface coil: a technical note, Skeletal Radiology, vol.27, issue.2, 1998.
DOI : 10.1007/s002560050341

M. Alley, T. Grist, and J. Swan, Development of a phased-array coil for the lower extremities, Magnetic Resonance in Medicine, vol.16, issue.2, 1995.
DOI : 10.1148/radiology.190.2.8284382

A. Cohen, J. Mcneill, E. Calkins, J. Sharp, and A. Schubart, The " normal " sacroiliac joint. Analysis of 88 sacroiliac roentgenograms, Am J Roentgenol Radium Ther Nucl Med, vol.34, issue.2, pp.260-267

J. Deng and A. Larson, Multishot Targeted PROPELLER Magnetic Resonance Imaging, Investigative Radiology, vol.44, issue.8, pp.454-62, 2009.
DOI : 10.1097/RLI.0b013e3181a8b015

URL : http://europepmc.org/articles/pmc2888134?pdf=render

A. Tamhane and K. Arfanakis, Motion correction in periodically-rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) and turboprop MRI, Magnetic Resonance in Medicine, vol.37, issue.1, pp.174-82, 2009.
DOI : 10.1002/mrm.22004

W. Nitz, Magnetic resonance imaging. Sequence acronyms and other abbreviations in MR imaging, pp.745-63, 2003.

S. Bayramoglu, O. Kilickesmez, T. Cimilli, A. Kayhan, G. Yirik et al., T2-weighted MRI of the Upper Abdomen:, Academic Radiology, vol.17, issue.3, pp.368-741038, 2009.
DOI : 10.1016/j.acra.2009.10.015

K. Arfanakis, A. Tamhane, J. Pipe, and M. Anastasio, k-space undersampling in PROPELLER imaging, Magnetic Resonance in Medicine, vol.21, issue.3, pp.675-83, 2005.
DOI : 10.1109/TNS.1974.6499235

J. Fritz, J. Henes, C. Thomas, S. Clasen, M. Fenchel et al., Diagnostic and Interventional MRI of the Sacroiliac Joints Using a 1.5-T Open-Bore Magnet: A One-Stop-Shopping Approach, American Journal of Roentgenology, vol.191, issue.6, pp.1717-1741, 2008.
DOI : 10.2214/AJR.08.1075

. De, avons pas testé tous les types de séquences et d'antennes disponibles: en effet l'impact sur le diagnostic positif de sacro-iliite des séquences pondérées T1 ainsi que des séquences réalisées après injection de gadolinium n'a pas été évalué dans notre étude

. Enfin, oedème osseux a été étudié: nous n'avons pas testé les autres critères diagnostics de sacro-iliite comme la présence d'une sclérose sous-chondrale, d'érosions des interlignes articulaires. Nous avons fait ce choix car la présence ou l'absence d'oedème est le critère fondamental retenu par les critères ASAS, puisqu'il s'agit du critère

. Fig, 4 ? Patiente âgée de 35 ans

. Fig, 5 ? Patient de 26 ans, HLA-B27 positif, avec un indice de masse corporelle à 27

B. 1. Haibel, H. Rudwaleit, M. Sieper, and J. , Outcome parameters in ankylosing spondylitis]. Z Für Rheumatol, pp.131-135, 2006.

A. Lacout, B. Rousselin, and J. Pelage, CT and MRI of Spine and Sacroiliac Involvement in Spondyloarthropathy, American Journal of Roentgenology, vol.191, issue.4, pp.1016-1039, 2008.
DOI : 10.2214/AJR.07.3446

M. Rudwaleit, A. Jurik, K. Hermann, R. Landewé, D. Van-der-heijde et al., Defining active sacroiliitis on magnetic resonance imaging (MRI) for classification of axial spondyloarthritis: a consensual approach by the ASAS/OMERACT MRI group, Annals of the Rheumatic Diseases, vol.68, issue.10, pp.1520-1527, 2009.
DOI : 10.1136/ard.2009.110767

J. Braun and J. Sieper, Ankylosing spondylitis. Lancet, pp.1379-90, 2007.
URL : https://hal.archives-ouvertes.fr/hal-00503871

L. Jans, C. Van-langenhove, V. Praet, L. Carron, P. Elewaut et al., Diagnostic value of pelvic enthesitis on MRI of the sacroiliac joints in spondyloarthritis, European Radiology, vol.72, issue.4
DOI : 10.1136/annrheumdis-2012-201545

R. Carmona, S. Harish, D. Linda, G. Ioannidis, M. Matsos et al., MR Imaging of the Spine and Sacroiliac Joints for Spondyloarthritis: Influence on Clinical Diagnostic Confidence and Patient Management, Radiology, vol.269, issue.1, pp.208-223, 2013.
DOI : 10.1148/radiol.13121675

C. Giraudo, S. Magnaldi, M. Weber, A. Puchner, H. Platzgummer et al., Optimizing the MRI protocol of the sacroiliac joints in Spondyloarthritis: which para-axial sequence should be used?, European Radiology, vol.37, issue.1, 2015.
DOI : 10.3899/jrheum.090519

T. Dietrich, E. Ulbrich, M. Zanetti, S. Fucentese, and C. Pfirrmann, PROPELLER Technique to Improve Image Quality of MRI of the Shoulder, American Journal of Roentgenology, vol.197, issue.6, pp.1093-100, 2011.
DOI : 10.2214/AJR.10.6065

L. Carucci, Imaging obese patients: problems and solutions. Abdom Imaging, 2013.

R. Uppot, D. Sahani, P. Hahn, D. Gervais, and P. Mueller, Impact of Obesity on Medical Imaging and Image-Guided Intervention, American Journal of Roentgenology, vol.188, issue.2, pp.433-473, 2007.
DOI : 10.2214/AJR.06.0409

K. Fujimoto, T. Koyama, K. Tamai, N. Morisawa, T. Okada et al., BLADE acquisition method improves T2-weighted MR images of the female pelvis compared with a standard fast spin-echo sequence, European Journal of Radiology, vol.80, issue.3, pp.796-801, 2011.
DOI : 10.1016/j.ejrad.2010.08.002

C. Ng and C. Palmer, Assessing Diagnostic Confidence, Academic Radiology, vol.15, issue.5, pp.584-92, 2008.
DOI : 10.1016/j.acra.2007.12.004

S. Rubin, S. Totterman, S. Meyers, and D. Hartley, Magnetic resonance imaging of the hip with a pelvic phased-array surface coil: a technical note, Skeletal Radiology, vol.27, issue.2, 1998.
DOI : 10.1007/s002560050341

M. Alley, T. Grist, and J. Swan, Development of a phased-array coil for the lower extremities, Magnetic Resonance in Medicine, vol.16, issue.2, 1995.
DOI : 10.1148/radiology.190.2.8284382

A. Cohen, J. Mcneill, E. Calkins, J. Sharp, and A. Schubart, The " normal " sacroiliac joint. Analysis of 88 sacroiliac roentgenograms, Am J Roentgenol Radium Ther Nucl Med, vol.34100, issue.23, pp.260-267, 1967.

J. Deng and A. Larson, Multishot Targeted PROPELLER Magnetic Resonance Imaging, Investigative Radiology, vol.44, issue.8, pp.454-62, 2009.
DOI : 10.1097/RLI.0b013e3181a8b015

URL : http://europepmc.org/articles/pmc2888134?pdf=render

A. Tamhane and K. Arfanakis, Motion correction in periodically-rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) and turboprop MRI, Magnetic Resonance in Medicine, vol.37, issue.1, pp.174-82, 2009.
DOI : 10.1002/mrm.22004

W. Nitz, Magnetic resonance imaging. Sequence acronyms and other abbreviations in MR imaging, pp.745-63, 2003.

S. Bayramoglu, O. Kilickesmez, T. Cimilli, A. Kayhan, G. Yirik et al., T2-weighted MRI of the Upper Abdomen:, Academic Radiology, vol.17, issue.3, pp.368-741038, 2009.
DOI : 10.1016/j.acra.2009.10.015

K. Arfanakis, A. Tamhane, J. Pipe, and M. Anastasio, k-space undersampling in PROPELLER imaging, Magnetic Resonance in Medicine, vol.21, issue.3, pp.675-83, 2005.
DOI : 10.1109/TNS.1974.6499235

J. Fritz, J. Henes, C. Thomas, S. Clasen, M. Fenchel et al., Diagnostic and Interventional MRI of the Sacroiliac Joints Using a 1.5-T Open-Bore Magnet: A One-Stop-Shopping Approach, American Journal of Roentgenology, vol.191, issue.6, pp.1717-1741, 2008.
DOI : 10.2214/AJR.08.1075