Learning objectives
1) Updates on the current classification criteria for peripheral seronegative spondyloarthritis (SpA).
2) Highlight imaging features of seronegative arthritis in non-axial joints that the radiologist should be aware of.
Background
In the last decade,
new clinical and imaging criteria have vastly improved the diagnosis and outcome of patients with seronegative spondyloarthritis (SpA).
Both axial and peripheral SpA have an approximate global prevalence of 1%.
It is estimated that up to 30% of patients with SpA may exhibit predominant (or only) peripheral manifestations of SpA.
Furthermore,
in several documented cases a diagnostic delay of up 8 to 9 years has occurred and it is therefore essential to diagnose and treat SpA as early as possible (1)....
Imaging findings OR Procedure Details
Case based imaging findings:
Both ultrasound (US) and MR imaging are highly specific to detect inflammatory and chronic enthesis-centred abnormalities. Clinically enthesitis is often underdiagnosed due to is poor quantification,
sensitivity and specificity.
On imaging however,
MR features of enthesitis are demonstrated by oedema and inflammatory foci within the soft tissue and bone marrow.
There is also particular involvement of the tendons,
ligaments,
fatty tissue and perientheseal synovium.
More chronic enthesopathic changes manifest as erosions and enthesophytes.
Typically inflammatory MR findings manifest as areas of...
Conclusion
Peripheral manifestations,
especially enthesitis,
dactylitis and arthritis are inherently manifestations of SpA.
Peripheral SpA can present to non rheumatologists and in these cases can be often misinterpreted and under-diagnosed by radiologists.Unexplained on going pain in a peripheral joint containing fibrocartilage should prompt the radiologist to check for imaging findings related to undiagnosed SpA.
Our pictorial review emphasises the importance of radiological assessment of extra-axial joints with findings of enthesitis and not forget SpA,
prompting early rheumatology referral.
References
1)Ramdin D,
Moorthy A,
Rennie WJ.
Classification Terminology and Definitions in Reporting of MRI in Axial Spondyloarthritis.J Belg Soc Radiol.
2017;101(Suppl 2):11.
Published 2017 Dec 16.
doi:10.5334/jbr-btr.1393
2)Khmelinskii N,
Regel A,
Baraliakos X.
The Role of Imaging in Diagnosing Axial Spondyloarthritis.Front Med (Lausanne).
2018;5:106.
Published 2018 Apr 17.
doi:10.3389/fmed.2018.00106
3) Chang EY,
Chen KC,
Huang BK,
Kavanaugh A.
Adult Inflammatory Arthritides: What the Radiologist Should Know.Radiographics.2016;36:1849–70.https://doi.org/10.1148/rg.2016160011.
4)Kucybała I,
Urbanik A,
Wojciechowski W.
Radiologic approach to axial spondyloarthritis: where are we now and where are we...