Abstract
Purpose and background:
MRI findings associated with spondyloarthritis (SpA) can be difficult to distinguish from the more prevalent findings of degeneration. Despite this, the two groups of MRI-findings are often evaluated in separate studies and in different study populations, which may reduce their applicability in daily clinical practice.
The purpose of this study was to estimate the prevalence of degenerative and SpA related MRI-findings in the spine and sacroiliac joints (SIJ) in patients with persistent LBP.
Methods:
Patients with persistent LBP (n=1037, median age 33 [IQR 27–37], 54% women) referred to an outpatient, secondary care and non-surgical department were included in the study. MRI of the whole spine and the SIJ was performed and degenerative and SpA-related MRI-findings were evaluated by experienced musculoskeletal radiologists.
Results:
The prevalence of disc degeneration, disc contour changes, and Modic changes were 87%(±1.1), 82%(±1.2) and 48%(±1.6). All degenerative spinal findings were most frequent in men and patients aged 30–40 years. Spinal SpA-related MRI-findings were rare. In the SIJ, 28%(±1.4) had at least one MRI finding, with bone marrow oedema (BMO) being the most common (21%(±1.3)). SIJ erosions were most prevalent in patients aged 18–29 years and BMO in patients aged 30–40 years. SIJ sclerosis and fatty marrow deposition were most common in women. Post hoc analysis showed that SIJ BMO, sclerosis and erosions were most frequent in women indicating pregnancy-related LBP.
Conclusion:
The high prevalence of SIJ MRI findings associated with age, gender, and pregnancy-related LBP need further investigation of their clinical importance in patients with persistent LBP.
