Diagnostic value of MRI parameters of the rotator interval in adhesive capsulitis

Objective: To investigate the diagnostic value of quantitative and qualitative MRI parameters of rotator interval (RI) in adhesive capsulitis. Methods: Contrast-enhanced MRI of 49 patients with and 54 patients without adhesive capsulitis was retrospectively analyzed. Using arthroscopy results as the gold standard, the width, depth and contrast enhancement of RI, obliteration of the subcoracoid fat, and thickness of the coracohumeral ligament were compared between the two groups. Results: There was significant difference in the width (ICC = 0.82), depth (ICC = 0.81) and contrast enhancement (κ = 0.98, 100% sensitivity, 77.6% specificity) of RI, obliteration of the subcoracoid fat (κ = 0.97, 95.9% sensitivity, 96.3% specificity), and thickness of the coracohumeral ligament (ICC = 0.84) between the two groups (P < 0.05). The RI width at cut off value of 11.95 mm was 82% sensitive and 90% specific whereas RI depth at cut off value of 5.95 mm was 92% sensitive and 90% specific for diagnosing adhesive capsulitis. Conclusion: The qualitative and quantitative MRI parameters of loss of subcoracoid fat, thickness of the coracohumeral ligament, RI width, depth, and contrast enhancement are helpful for diagnosing adhesive capsulitis. (authors)