CT arthrography of adhesive capsulitis of the shoulder: Are MR signs applicable?

Abstract Objective To determine if diagnostic signs of adhesive capsulitis (AC) of the shoulder at Magnetic Resonance Imaging (MRI) and arthrography (MRA) are applicable to CT arthrography (CTA). Methods 22 shoulder CTAs with AC were retrospectively reviewed for features described in MR literature. The control group was composed of 83 shoulder CTA divided into four subgroups 1) normal (N=20), 2) omarthrosis (N=19), 3) labral injury (N=23), and 4) rotator cuff tear (N=21). Two musculoskeletal radiologists assessed the rotator interval (RI) for obliteration, increased width and thickening of coracohumeral ligament (CHL). The width and capsule thickness of the axillary recess were measured. Results The width of the axillary recess was significantly decreased in the AC group (4.6±2.6mm versus 9.9±4.6mm, p≤0.0001; sensitivity and specificity of 84% and 80%). Thickness of the medial and lateral walls of the axillary capsule was significantly increased in the AC group (5.9±1.3mm versus 3.7±1.1mm, p≤0.0001 and 5.7±1mm versus 3.5±1.3mm, p≤0.0001, respectively). CHL thickness was significantly increased in the AC group (4.1±1mm (p≤0.001)) in comparison to others groups. Obliteration of the RI was statistically significantly more frequent in patients with AC (72.7% (16/22) vs. 12% (10/83), p Conclusion Decreased axillary width, and thickened axillary capsule are MR signs of AC applicable to CTA. Evaluation of rotator interval seems useful and reproducible only for obliteration.