3D volumetric MR arthrographic assessment of shoulder joint capacity in patients with primary adhesive capsulitis

To evaluate the three-dimensional (3D) volumetric MR arthrographic findings of shoulder joint capacity in patients with primary adhesive capsulitis.

Thin-section 3D volumetric MR arthrography sequences of the shoulder joint were obtained in 28 patients with clinically and radiologically proven primary adhesive capsulitis and in 25 controls. Volumetric measurements of the total glenohumeral joint capacity, extra-articular contrast material leakage, and the rotator interval, axillary recess, and biceps tendon sheath capacities were performed for the study and control groups.

Mean volume of the rotator interval was 7.67 ± 2.6 cm³ in the study group, which was significantly lower than in the control group (12.31 ± 2.5 cm³) (p < 0.0001). Mean volume of the bicipital groove was significantly decreased in the patient group compared to the control group (1.67 ± 0.9 cm³ vs 2.88 ± 0.9 cm³) (p ≤ 0.0001). Mean volume of extra articular contrast material extravasation was 9.93 ± 1.7 cm³ in the patient group, which was significantly higher than in the control group (5.1 ± 1.4 cm³) (p = 0.002). Mean total glenohumeral joint volume was 22.52 ± 1.1 cm³ in the patient group and 26.01 ± 1.2 cm³ in the control group (p = 0.003).

On 3D volumetric MR arthrographic examination, obliterations in the biceps tendon sheath and rotator interval as well as decreased joint capacity may be useful imaging criteria for diagnosing primary adhesive capsulitis.

In the present study, MR arthrography showed contrast material extravasation in 71% of the patients and showed extra articular contrast material extravasation in 48% of the control subjects. On 3D volumetric MR arthrographic examination, obliterations in the biceps tendon sheath and rotator interval as well as decreased joint capacity may be useful imaging criteria for diagnosing primary adhesive capsulitis.In patients with primary adhesive capsulitis, thin-section 3D volumetric MR arthrography is a useful imaging modality to evaluate both joint capacity and capsular structure.