Background: Rheumatoid arthritis (RA) is a systemic autoimmune disease that has a great impact on different joints, may result in their destruction and loss of function.Although the shoulder is affected in a large portion of patients with RA, it does not receive much attention during the follow up of RA. The precise diagnosis of shoulder pain in RA is a clinical challenge and benefits from a reliable imaging modality to detect its exact origin.
Aim:To determine the diagnostic accuracy of ultrasound (US) in detecting shoulder joint pathologies in RA, considering magnetic resonance imaging (MRI) as the gold standard.
Materials and Methods:This cross-sectional, observational study was carried out on 30 RA patients complaining of unilateral or bilateral shoulder pain. Patients were subjected to history taking, clinical shoulder examination, plain X-ray, US examination following a standardized protocol, and MRI. The results were correlated with each other.
Results:In comparison with the MRI findings, US showed high accuracy in terms of sensitivity (Sn) and specificity (Sp) in supraspinatus tendinopathy (Sn 96.6%; Sp 93.3%), biceps tenosynovitis (Sn 87.5%; Sp 97.6%), subacromial-subdeltoid bursitis (Sn 72.7%; Sp 95.7%), humeral erosions (Sn 90.5%; Sp 97.3%), and acromioclavicular osteoarthritis (Sn 85.7%; Sp 95.7%). In terms of reliability, the agreement between US and MRI was almost perfect (κ = .9, P < .001).
Conclusion:US may have a role as the initial imaging modality in RA patients with shoulder pain, as it is highly sensitive and specific in detecting different pathological abnormalities of the shoulder. K E Y W O R D S MRI, rheumatoid arthritis, shoulder, ultrasound | 2159 ABDELZAHER Et AL.