MR imaging of the normal sacroiliac joint with correlation to histology

Abstract

The SIJ should be classified anatomically as a symphysis with some characteristics of a synovial joint being confined to the distal cartilaginous portion at the iliac side. Coronal MR imaging does not allow assessment of normal anatomy, variants or abnormalities of the ventral and dorsal margins of the cartilaginous SIJ.

Limited role of gadolinium to detect active sacroiliitis on MRI in juvenile spondyloarthritis

“…To the best of our knowledge, no studies around this topic are published in children. In the adult population, we found one study reporting fluid in the SI joint space in half of their study patients [23]. In our study, nearly all patients with high STIR signal in the joint (15/18) also had other MRI findings of sacroiliitis, while the three that had high STIR signal in the joint space as an isolated finding were all negative for JSpA clinically.…”

Assessment of spinal pain

“…The typical findings of MRI are not only bone marrow edema ("sacroiliitis"), which have been shown to correlate with histologic and immunohistologic findings as well as with clinical symptoms [33], but also capsulitis, enthesitis, and synovitis of the sacroiliac joint. Furthermore, MRI can also be used for detection of structural changes in the bone, such as subchondral erosions, periarticular fat deposition, sclerosis (the equivalent to the old term "sacroiliitis" on conventional radiographs), and ankylosis.…”

Diagnostic Utility of MRI in Early Spondyloarthritis

“…This has been ascribed to the presence of synovitis [5], although this seems unlikely because histologic data show no synovium in the joint cavity [9]. It is more likely that this reflects the hyperemia associated with subchondral inflammation occurring in a linear pattern.…”