What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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Findings There is a prominent amount of edema about both sacroiliac (SI) joints with dense, low signal about the subchondral bone of the SI joints. No erosions are identified and there is no prominent, subchondral fatty deposition. Other imaging findings are present which will be discussed later.
What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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Diagnosis: Post-partum Edema of the SI Joints Mimicking Sacroilitis During pregnancy, mechanical stress and additionally increased amount of the hormone relaxin allow for the ligaments about the pubis and sacroiliac joints to accommodate for pregnancy and the birthing process. As a consequence many women suffer from pain at these locations often referred to as “pelvic girdle syndrome”. On MRI, it has been shown that there can often be a marked edema pattern about the SI joints as in this case. A little bit more of an “eye test” than some of the previous cases were the clues to recent pregnancy in this patient.
What’s the Diagnosis – Case 134
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What’s the Diagnosis – Case 134
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Discussion The widened pubis and recently gravid uterus are subtle but not intended to be the thrust of the case. The main issue is understanding that many women can have persistent back pain for up to 2 years following delivery and it is an important diagnostic consideration. The findings on the MRI and particularly the marked edema pattern of the SI joints would quickly make one entertain the diagnosis of an inflammatory arthritis and rightfully so. History would help in coming to the appropriate diagnosis but in addition, in the setting of postpartum changes about the SI joints erosions and subchondral fatty deposition are frequently absent which is the case here. Clearly an inflammatory arthritis can present in women of this age but paying close attention to imaging findings, obtaining pertinent history, and most importantly being aware of this entity should hopefully point us in the right direction.
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References Postpartum Bone Marrow Edema at the Sacroiliac Joints May Mimic Sacroiliitis of Axial Spondyloarthritis on MRI. Agten CA, Zubler V, Zanetti M, Binkert CA, Kolokythas O, Prentl E, Buck FM, Pfirrmann CWA. AJR Am J Roentgenol. 2018 Dec;211(6):1306-1312. doi: 10.2214/AJR.17.19404. Epub 2018 Sep 24. Peripartum changes of the sacroiliac joints on MRI: increasing mechanical load correlating with signs of edema and inflammation kindling spondyloarthropathy in the genetically prone. Eshed I, Miloh-Raz H, Dulitzki M, Lidar Z, Aharoni D, Liberman B, Lidar M. Clin Rheumatol. 2015 Aug;34(8):1419-26. doi: 10.1007/s10067-015-2976-0. Epub 2015 May 26.
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