MRI abnormalities of sacroiliac joints in early spondylarthropathy: a 1-year follow-up study.
OBJECTIVE
To describe changes in chronic and acute magnetic resonance imaging (MRI) abnormalities of the sacroiliac joints (SIJs) in early spondylarthropathy (SpA), and to associate these findings with computed tomography (CT), X-ray, and clinical findings during a 1-year follow-up.


METHODS
Thirty-four patients, 20 males and 14 females, median age 27 years, with inflammatory low back pain (median 23 months) were included. MRI, CT, and X-ray, as well as clinical and laboratory tests were performed. After a follow-up period of 1 year (median 377 days) the examinations were repeated, and the findings were correlated.


RESULTS
MRI and CT changes resulting from SIJ destruction increased significantly during follow-up, and the two modalities were significantly correlated. For the MRI findings of inflammatory activity, only bone marrow oedema decreased significantly. An increase in the Schober test was the only clinical examination that changed significantly.


CONCLUSIONS
In early SpA, MRI can detect significant inflammatory and destructive changes of the SIJs over a 1-year follow-up period, in spite of minimal changes in the clinical parameters. The MRI changes in inflammatory activity are not detectable by CT and X-ray examinations. Thus, MRI may be a sensitive method, without known risks, for early diagnosis and for following disease progression in SpA.
Puhakka
K B
KB
Department of Radiology, Aarhus University Hospital, Denmark. kbpuh@akh.aaa.dk
Jurik
A G
AG
Schiøttz-Christensen
B
B
Hansen
G V O
GV
Egund
N
N
Christiansen
J V
JV
Stengaard-Pedersen
K
K
D000328:Adult; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007596:Joints / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010146:Pain; D011859:Radiography; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging / Q000473:pathology*; D025241:Spondylarthritis / Q000000981:diagnostic imaging / Q000473:pathology*; D013997:Time Factors