SAT0258 A Prospective Evaluation of the Diagnostic Value of Conventional Radiography, Ultrasound and MRI in Comparison to Clinical Examination for the Assessment of Heel and Knee Enthesitis in Patients With Spondyloarthritis and Controls

Background Spondyloarthritides (SpA) are characterized by inflammatory and structural changes in the axial skeleton and in peripheral joints and entheses. Imaging has an essential role in the new classification criteria for axial SpA (axSpA) but not for peripheral manifestations. This is largely due to limited knowledge about the value of imaging to detect peripheral arthritis and enthesitis in SpA and whether it differentiates SpA from other conditions (non-SpA). Objectives To evaluate the significance of imaging procedures and their influence on treatment decision in patients with peripheral involvement of the lower limbs in SpA vs. non-SpA. Methods The main inclusion criterion was a painful heel or knee as reported by the patients, independent of the current treatment, and age Results The groups were similar in mean age (37.2±6.8 years), CRP (0.6±0.9mg/dl), NRS-pain (6.1±2.1) but symptom duration (SpA: 17.2±27.5 vs. non-SpA: 4.4±4.3 months) and HLA-B27 (67% in axSpA vs. 13% in non-SpA) differed (both n Pathologic findings were discovered most frequently using MRI of the heel (85.3% of patients), while x-rays were regarded pathologic in only 16.7% of patients (p Based on the clinical evaluation only, a change in treatment was suggested in 47% and 57% of patients with axSpA and non-SpA, respectively. Imaging (only US and MRI) contributed to a change of medication in an additional 13% of patients with axSpA but not in non-SpA patients. Conclusions In symptomatic patients with peripheral involvement of the knee or the heel, only erosions in the Achilles tendon area as assessed by US and thickness of the patellar tendon as assessed by MRI helped to differentiate SpA from non-SpA patients, while active enthesitis did not. Imaging of peripheral sites helped to make treatment decisions in patients with axSpA. Disclosure of Interest None Declared