Spectrum of Inflammatory Changes in the SIJs on Radiographs and MR Images in Patients with Suspected Axial Spondyloarthritis

Abstract

SummaryBackgroundThe aim of the paper was to compare radiographs and MRI in assessment of active and chronic inflammatory changes in the sacroiliac joints in patients with chronic back pain and suspected axial spondyloarthritis.Moreover, the aim was to determine which of the two methods is more accurate in diagnosing individual inflammatory changes in the sacroiliac joints and whether there is a correlation between radiographs and MRI in their identification.Material/MethodsThe analysis was conducted in a group of 101 patients, including 61 women and 40 men, referred to radiographs and MR examinations by rheumatologists due to chronic back pain.AP images of the lumbar region of the spine were performed in each patient in the supine position. The images included the sacroiliac joints. Changes in the SIJs were assessed based on the New York criteria of 1966. In MR examination, the SIJs were assessed in terms of the presence of active and chronic inflammatory changes described by the ASAS. The statistical analysis of the variables tested was conducted in the Excel and Statistica systems.ResultsIn relation to the final clinical diagnosis of axSpA, MRI had higher sensitivity and specificity than radiography in diagnosing sacroiliitis (sensitivity: 71% vs. 22%, specificity: 90% vs. 94% on radiographs according to New York criteria. In relation to MRI, radiographs resulted in 40% of incorrect sacroiliitis diagnoses (both false positive and false negative results). In as many as 50% of cases (7/14), MRI failed to confirm the presence of inflammatory changes in the sacroiliac joints observed in radiography according to the modNY criteria (false positive results on radiographs).Both examinations are characterised by very low agreement, which is near to random, in assessing individual features of sacroiliitis, such as sclerosis, change in the joint space width, erosions and ankylosis.Conclusions1. Radiographs do not allow early inflammatory lesions indicating sacroiliitis to be diagnosed, which leads to diagnostic delay. MRI is the method of choice in diagnosing early sacroiliitis and detecting structural lesions, in particular sclerosis and erosions. 2. Radiographs and MRI are characterised by low, near to random, agreement in the detectability of the individual inflammatory changes in the sacroiliac joints.

Correlation Between Expression of High Temperature Requirement Serine Protease A1 (HtrA1) in Nucleus Pulposus and T2 Value of Magnetic Resonance Imaging

“…MRI is helpful for diagnosis of spondylodiscitis, sacroiliitis, and other spinal disorders [ 28 , 29 ]. MRI is also one of the most widely used and accurate methods to evaluate the degree of disc degeneration.…”

Australian Consensus Statements for the Assessment and Management of Non-radiographic Axial Spondyloarthritis

“…AP pelvic radiographs are often sufficient for diagnosis in suspected axSpA, so should be performed before sacroiliac MRI. They have moderate sensitivity (40-70%) and high specificity (86-95%) for axSpA compared to low-dose CT but low sensitivity (20-50%), and high specificity (80-99%) compared to expert diagnosis [48][49][50][51].…”

Diagnostic performance of plain radiography for sacroiliitis in patients with suspected axial spondyloarthritis: a systematic review and meta-analysis

“…The study characteristics and demographics of the eight studies are summarized in Table 1 (10,(21)(22)(23)(24)(25)(26)(27). A total of 1597 patients were included for meta-analysis.…”