Prospective evaluation of MR arthrography performed with high-volume intraarticular saline enhancement in patients with recurrent anterior dislocations of the shoulder.

Abstract

The purpose of this study was to evaluate the accuracy of high-volume saline-enhanced MR arthrography in assessing the labrum, the ligaments, and the bony components of the glenohumeral joint. Forty-four patients with recurrent anterior dislocations of the shoulder underwent MR arthrography after intraarticular injection of 15-40 ml of saline solution. Two-dimensional fast low-angle shot and T1-weighted spin-echo sequences were prospectively evaluated by two observers. Anterior (Bankart) lesions, superior labral lesions extending from anterior to posterior, and Hill-Sachs lesions were diagnosed. Glenohumeral ligaments (GHLs) were identified and classified using a standard system. MR imaging results were compared with those of arthroscopy (n = 32) or open surgery (n = 12), either of which was the gold standard. Bankart lesions and superior labral lesions extending from anterior to posterior were revealed with a sensitivity of 93% and 89%, respectively, and a specificity of 80% and 89%, respectively. Diagnostic accuracy was 89% for both types of lesions. All six patients with bony Bankart lesions had high fat-marrow signal intensity within the fragment on T1-weighted MR images. For GHLs, MR imaging results and arthroscopy correlated in 25 of the 31 patients. In three patients all three GHLs were visible on MR imaging, but only two GHLs were detected with arthroscopy. In three patients two GHLs were detected on MR imaging but all three were visible on arthroscopy. Hill-Sachs lesions were revealed with a sensitivity of 95%, a specificity of 50%, and an accuracy of 81%. High-volume saline-enhanced MR arthrography is accurate in revealing the labrum, the ligaments, and the bony components of the glenohumeral joint Saline solution is inert and inexpensive, two advantages over gadopentetate dimeglumine.