Value of Metacarpophalangeal and Proximal Interphalangeal Joints Ultrasound in Early Rheumatoid Arthritis, Comparison with Magnetic Resonance Imaging, A Cross-Sectional Study

Abstract

Background: The metacarpophalangeal and interphalangeal joints are very early sites of affection by Rheumatoid arthritis and are suitable for ultrasound evaluation; the purpose of the study is to evaluate the diagnostic value of ultrasound in detecting radiological signs of early Rheumatoid arthritis as compared to magnetic resonance imaging. Results: The most frequent radiological finding was synovial thickening in both US and MRI (84.3% versus 89.3%), followed by erosion (34.3% versus 32.1%) and effusion (11.4%versus 10%), while the least was tenosynovitis (4.3%in both US and MRI). US showed high sensitivity (94.4%, 100% and 100%), specificity (100%, 98.4% and 100%) and accuracy(95%, 98.5% and 100%) for synovial thickening, effusion and tenosynovitis respectively and a lower sensitivity(84.4%), specificity(89.5%) and accuracy(87.8%) in detecting bone erosions in the finger joints compared to MRI. Conclusion: US is a reliable method in diagnosing most features of early Rheumatoid arthritis compared to MRI. Therefore, the US can be implemented as a primary diagnostic tool in evaluating early Rheumatoid arthritis.