Correlation Between Ultrasonography and Magnetic Resonance Imaging in the Diagnosis of Adhesive Capsulitis: A Prospective Study

IntroductionAdhesive capsulitis is a painful and disabling shoulder disorder characterized by progressive restriction of active and passive movements.Although magnetic resonance imaging (MRI) provides comprehensive assessment of capsular and periarticular abnormalities, its cost and limited availability may restrict its use.This study evaluated the correlation and agreement between ultrasonography (USG) and MRI findings and assessed the diagnostic performance of selected ultrasonographic parameters against MRI-based classification in adhesive capsulitis. Materials and methodsA prospective comparative diagnostic study was conducted among 35 patients with clinically suspected or diagnosed adhesive capsulitis at the Department of Radio-Diagnosis, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru.All participants underwent high-resolution USG followed by MRI.Coracohumeral ligament (CHL) thickness, axillary recess (AR) thickness, rotator interval (RI) soft-tissue abnormality, and joint capsule thickening were assessed.MRI-based classification was used as the reference classification.Pearson correlation, diagnostic performance measures, receiver operating characteristic (ROC) analysis, and Cohen's kappa agreement analysis were used for statistical evaluation. ResultsMRI classified adhesive capsulitis as positive in 26 (74.3%) participants.Mean CHL and AR thicknesses were higher among MRI-positive participants.Strong correlation was observed between USG and MRI measurements for CHL thickness (r=0.861) and AR thickness (r=0.931).Both CHL and AR demonstrated excellent discriminatory performance on ROC analysis (area under the curve (AUC)=0.987for each parameter).RI abnormality and joint capsule thickening showed substantial agreement between USG and MRI. ConclusionUSG demonstrated strong correlation and substantial agreement with MRI-based findings for selected quantitative and qualitative parameters associated with adhesive capsulitis.A structured multi-parameter ultrasound assessment may have potential as a practical initial imaging approach, particularly in settings with limited access to MRI.Given the small single-centre cohort, use of MRI-based classification, and lack of independent validation, these findings should be considered preliminary and require confirmation in larger multicentre studies.