Sacroiliac Joint: Mimics and Pitfalls

Abstract

Sacroiliac joint pathology presents a complex diagnostic challenge due to the diverse range of conditions, both mechanical and inflammatory, that can affect the joint. Although axial spondyloarthritis–related sacroiliitis is often the most recognized pathology, numerous other conditions closely mimic axial spondyloarthritis in both clinical presentation and imaging features. This review describes key anatomical aspects of the sacroiliac joint, including its distinct morphology, ligamentous support, and histologic characteristics, essential for understanding and differentiating various pathologies. It also examines detailed imaging findings from magnetic resonance imaging, computed tomography, and radiography in relation to each pathologic condition. By providing a framework for distinguishing between common and rare sacroiliac joint disorders and axial spondyloarthritis, this article will enhance diagnostic accuracy and offer insights into the anatomical nuances that impact clinical and imaging assessments.

Keywords

sacroiliitis - inflammatory arthropathy - sacroiliac joint - variants

Publication History

Article published online:
31 March 2025

• References

• 1 Cohen SP. Sacroiliac joint pain: a comprehensive review of anatomy, diagnosis, and treatment. Anesth Analg 2005; 101 (05) 1440-1453
• 2 Herzog W, Conway PJ. Gait analysis of sacroiliac joint patients. J Manipulative Physiol Ther 1994; 17 (02) 124-127
• 3 Bernard Jr TN, Kirkaldy-Willis WH. Recognizing specific characteristics of nonspecific low back pain. Clin Orthop Relat Res 1987; (217) 266-280
• 4 Vleeming A, Schuenke MD, Masi AT, Carreiro JE, Danneels L, Willard FH. The sacroiliac joint: an overview of its anatomy, function and potential clinical implications. J Anat 2012; 221 (06) 537-567
• 5 McLauchlan GJ, Gardner DL. Sacral and iliac articular cartilage thickness and cellularity: relationship to subchondral bone end-plate thickness and cancellous bone density. Rheumatology (Oxford) 2002; 41 (04) 375-380
• 6 Egund N, Jurik AG. Anatomy and histology of the sacroiliac joints. Semin Musculoskelet Radiol 2014; 18 (3) 332-339
• 7 Prassopoulos PK, Faflia CP, Voloudaki AE, Gourtsoyiannis NC. Sacroiliac joints: anatomical variants on CT. J Comput Assist Tomogr 1999; 23 (02) 323-327
• 8 Trentadue TP, Anderson TL, Wenger DE, McKenzie GA. Prevalence of accessory sacroiliac joint anatomy and associated clinical features. Skeletal Radiol 2023; 52 (07) 1359-1368
• 9 Trotter M. Accessory sacro-iliac articulations. Am J Phys Anthropol 1937; 22 (02) 247-261
• 10 Slobodin G, Lidar M, Eshed I. Clinical and imaging mimickers of axial spondyloarthritis. Semin Arthritis Rheum 2017; 47 (03) 361-368
• 11 Hadley LA. Accessory sacroiliac articulations with arthritic changes. Radiology 1950; 55 (03) 403-409
• 12 Ziegeler K, Hermann KGA, Diekhoff T. Anatomical joint form variation in sacroiliac joint disease: current concepts and new perspectives. Curr Rheumatol Rep 2021; 23 (08) 60
• 13 Kim Y, Chee CG, Kim J. et al. Diagnostic performance of plain radiography for sacroiliitis in patients with suspected axial spondyloarthritis: a systematic review and metaanalysis. Acta Radiologica 2021; 62 (04) 500-509
• 14 Mandl P, Navarro-Compán V, Terslev L. et al. EULAR recommendations for the use of imaging in the diagnosis and management of spondyloarthritis in clinical practice. Annals of the Rheumatic Diseases 2015; 74 (07) 1327-1339
• 15 Czuczman GJ, Mandell JC, Wessell DE. et al. Expert panel on musculoskeletal imaging. ACR appropriateness criteria(R) inflammatory back pain: known or suspected axial spondyloarthritis: 2021 update. J Am Coll Radiol 2021; 18 (11S): S340-S360
• 16 Diekhoff T, Eshed I, Radny F. et al. (2022). Choose wisely: imaging for diagnosis of axial spondyloarthritis. Annals of the Rheumatic Diseases 2022; 81 (02) 237-242
• 17 Navallas M, Ares J, Beltrán B, Lisbona MP, Maymó J, Solano A. Sacroiliitis associated with axial spondyloarthropathy: new concepts and latest trends. Radiographics 2013; 33 (04) 933-956
• 18 Canella C, Schau B, Ribeiro E, Sbaffi B, Marchiori E. MRI in seronegative spondyloarthritis: imaging features and differential diagnosis in the spine and sacroiliac joints. AJR Am J Roentgenol 2013; 200 (01) 149-157
• 19 Poddubnyy D.. (2020). Classification vs. diagnostic criteria: the challenge of diagnosing axial spondyloarthritis. Rheumatology 2020; 59 (Supplement_4): iv6-iv17
• 20 Diekhoff T, Lambert R, Hermann KG. (2022). MRI in axial spondyloarthritis: understanding an ‘ASAS-positive MRI’ and the ASAS classification criteria. Skeletal Radiology 2022; 51 (09) 1721-1730
• 21 Maksymowych WP, Lambert RG, Østergaard M. et al. MRI lesions in the sacroiliac joints of patients with spondyloarthritis: an update of definitions and validation by the ASAS MRI working group. Annals of the Rheumatic Diseases 2019; 78 (11) 1550-1558
• 22 Weber U, Jurik AG, Zejden A. et al. Frequency and anatomic distribution of magnetic resonance imaging features in the sacroiliac joints of young athletes: exploring “background noise” toward a data-driven definition of sacroiliitis in early spondyloarthritis. Arthritis Rheumatol 2018; 70 (05) 736-745
• 23 de Winter J, de Hooge M, van de Sande M. et al. Magnetic resonance imaging of the sacroiliac joints indicating sacroiliitis according to the Assessment of SpondyloArthritis International Society definition in healthy individuals, runners, and women with postpartum back pain. Arthritis Rheumatol 2018; 70 (07) 1042-1048
• 24 Eshed I, Miloh-Raz H, Dulitzki M. et al. Peripartum changes of the sacroiliac joints on MRI: increasing mechanical load correlating with signs of edema and inflammation kindling spondyloarthropathy in the genetically prone. Clin Rheumatol 2015; 34 (08) 1419-1426
• 25 Bakker PAC, Ramiro S, Ez-Zaitouni Z. et al. Is it useful to repeat magnetic resonance imaging of the sacroiliac joints after three months or one year in the diagnosis of patients with chronic back pain and suspected axial spondyloarthritis?. Arthritis Rheumatol 2019; 71 (03) 382-391
• 26 Wurdinger S, Humbsch K, Reichenbach JR, Peiker G, Seewald HJ, Kaiser WA. MRI of the pelvic ring joints postpartum: normal and pathological findings. J Magn Reson Imaging 2002; 15 (03) 324-329
• 27 Major NM, Helms CA. Pelvic stress injuries: the relationship between osteitis pubis (symphysis pubis stress injury) and sacroiliac abnormalities in athletes. Skeletal Radiol 1997; 26 (12) 711-717
• 28 Ahovuo JA, Kiuru MJ, Visuri T. Fatigue stress fractures of the sacrum: diagnosis with MR imaging. Eur Radiol 2004; 14 (03) 500-505
• 29 Berthelot JM, le Goff B, Maugars Y, Laredo JD. Sacroiliac joint edema by MRI: far more often mechanical than inflammatory?. Joint Bone Spine 2016; 83 (01) 3-5
• 30 Resnick D, Niwayama G, Goergen TG. Comparison of radiographic abnormalities of the sacroiliac joint in degenerative disease and ankylosing spondylitis. AJR Am J Roentgenol 1977; 128 (02) 189-196
• 31 Resnick D, Niwayama G. Radiographic and pathologic features of spinal involvement in diffuse idiopathic skeletal hyperostosis (DISH). Radiology 1976; 119 (03) 559-568
• 32 Resnick D, Shapiro RF, Wiesner KB, Niwayama G, Utsinger PD, Shaul SR. Diffuse idiopathic skeletal hyperostosis (DISH) [ankylosing hyperostosis of Forestier and Rotes-Querol]. Semin Arthritis Rheum 1978; 7 (03) 153-187
• 33 Resnick D, Shaul SR, Robins JM. Diffuse idiopathic skeletal hyperostosis (DISH): Forestier's disease with extraspinal manifestations. Radiology 1975; 115 (03) 513-524
• 34 Prakash D, Prabhu SM, Irodi A. Seronegative spondyloarthropathy-related sacroiliitis: CT, MRI features and differentials. Indian J Radiol Imaging 2014; 24 (03) 271-278
• 35 Mitra R. Osteitis condensans ilii. Rheumatol Int 2010; 30 (03) 293-296
• 36 Eshed I, Lidar M. MRI findings of the sacroiliac joints in patients with low back pain: alternative diagnosis to inflammatory sacroiliitis. Isr Med Assoc J 2017; 19 (11) 666-669
• 37 Jenks K, Meikle G, Gray A, Stebbings S. Osteitis condensans ilii: a significant association with sacroiliac joint tenderness in women. Int J Rheum Dis 2009; 12 (01) 39-43
• 38 Ma L, Gao Z, Zhong Y, Meng Q. Osteitis condensans ilii may demonstrate bone marrow edema on sacroiliac joint magnetic resonance imaging. Int J Rheum Dis 2018; 21 (01) 299-307
• 39 Antonelli MJ, Magrey M. Sacroiliitis mimics: a case report and review of the literature. BMC Musculoskelet Disord 2017; 18 (01) 170
• 40 Olivieri I, Ferri S, Barozzi L. Osteitis condensans ilii. Br J Rheumatol 1996; 35 (03) 295-297
• 41 Bennett J, Suliburk JW, Morón FE. Osseous manifestations of primary hyperparathyroidism: imaging findings. Int J Endocrinol 2020; 2020: 3146535
• 42 Chang CY, Rosenthal DI, Mitchell DM, Handa A, Kattapuram SV, Huang AJ. Imaging findings of metabolic bone disease. Radiographics 2016; 36 (06) 1871-1887
• 43 Resnick D, Niwayama G. Subchondral resorption of bone in renal osteodystrophy. Radiology 1976; 118 (02) 315-321
• 44 Kreutzinger V, Diekhoff T, Liefeldt L, Poddubnyy D, Hermann KGA, Ziegeler K. Asymptomatic secondary hyperparathyroidism can mimic sacroiliitis on computed tomography. Sci Rep 2021; 11 (01) 4323
• 45 Rosenthal AK. Pseudogout: presentation, natural history, and associated conditions. In: Wortmann RL, Schumacher Jr HR, Becker MA, Ryan LM. eds. Crystal-Induced Arthropathies: Gout, Pseudogout, and Apatite-Associated Syndromes. Boca Raton, FL: CRC Press; 2006: 99
• 46 Wickrematilake GW. Calcium pyrophosphate dihydrate deposition disease in young patients: two case reports. Arch Rheumatol 2016;32
• 47 Wu J, Wei L, Zhong JCT. Imaging features of calcium pyrophosphate dihydrate crystal deposition involving spine. Journal of Radiation Research and Applied Sciences 2024;17(02);
• 48 el Maghraoui A, Lecoules S, Lechevalier D, Magnin J, Eulry F. Acute sacroiliitis as a manifestation of calcium pyrophosphate dihydrate crystal deposition disease. Clin Exp Rheumatol 1999; 17 (04) 477-478
• 49 Moreno Martinez MJ, Moreno Ramos MJ, Linares Ferrando LF. Sacroiliitis due to calcium pyrophosphate deposition disease. Reumatol Clin (Engl Ed) 2018; 14 (03) 175-176
• 50 Duran Tİ, Özgen M. Two cases of calcium pyrophosphate deposition disease (CPPD) presented with spondylodiscitis. Eur J Rheumatol 2020; 7 (02) 84-87
• 51 Jurik AG. Diagnostics of sacroiliac joint differentials to axial spondyloarthritis changes by magnetic resonance imaging. J Clin Med 2023; 12 (03) 1039
• 52 Depasquale R, Kumar N, Lalam RK. et al. SAPHO: What radiologists should know. Clin Radiol 2012; 67 (03) 195-206
• 53 Jansson A, Renner ED, Ramser J. et al. Classification of non-bacterial osteitis: retrospective study of clinical, immunological and genetic aspects in 89 patients. Rheumatology (Oxford) 2007; 46 (01) 154-160
• 54 Nguyen MT, Borchers A, Selmi C, Naguwa SM, Cheema G, Gershwin ME. The SAPHO syndrome. Semin Arthritis Rheum 2012; 42 (03) 254-265
• 55 Cao Y, Li C, Xu W. et al. Spinal and sacroiliac involvement in SAPHO syndrome: a single center study of a cohort of 354 patients. Semin Arthritis Rheum 2019; 48 (06) 990-996
• 56 de Mello FM, Helito PV, Bordalo-Rodrigues M, Fuller R, Halpern AS. Axial gout is frequently associated with the presence of current tophi, although not with spinal symptoms. Spine 2014; 39 (25) E1531-E1536
• 57 Namas R, Hegazin SB, Memişoğlu E, Joshi A. Lower back pain as a manifestation of acute gouty sacroiliitis: utilization of dual-energy computed tomography (DECT) in establishing a diagnosis. Eur J Rheumatol 2019; 6 (04) 216-218
• 58 Spermon J, Van Dijke CF. Dual energy CT: added value in gouty arthritis. JBR-BTR 2013; 96 (01) 34-37
• 59 Bongartz T, Glazebrook KN, Kavros SJ. et al. Dual-energy CT for the diagnosis of gout: an accuracy and diagnostic yield study. Ann Rheum Dis 2015; 74 (06) 1072-1077
• 60 Mallinson PI, Reagan AC, Coupal T, Munk PL, Ouellette H, Nicolaou S. The distribution of urate deposition within the extremities in gout: a review of 148 dual-energy CT cases. Skeletal Radiol 2014; 43 (03) 277-281
• 61 Glazebrook KN, Guimarães LS, Murthy NS. et al. Identification of intraarticular and periarticular uric acid crystals with dual-energy CT: initial evaluation. Radiology 2011; 261 (02) 516-524
• 62 Mancarella L, De Santis M, Magarelli N, Ierardi AM, Bonomo L, Ferraccioli G. Septic sacroiliitis: an uncommon septic arthritis. Clin Exp Rheumatol 2009; 27 (06) 1004-1008
• 63 Kang Y, Hong SH, Kim JY. et al. Unilateral sacroiliitis: differential diagnosis between infectious sacroiliitis and spondyloarthritis based on MRI findings. AJR Am J Roentgenol 2015; 205 (05) 1048-1055
• 64 Muche B, Bollow M, François RJ, Sieper J, Hamm B, Braun J. Anatomic structures involved in early- and late-stage sacroiliitis in spondylarthritis: a detailed analysis by contrast-enhanced magnetic resonance imaging. Arthritis Rheum 2003; 48 (05) 1374-1384
• 65 François RJ, Gardner DL, Degrave EJ, Bywaters EG. Histopathologic evidence that sacroiliitis in ankylosing spondylitis is not merely enthesitis. Arthritis Rheum 2000; 43 (09) 2011-2024