Advanced imaging of the glenohumeral ligaments

Abstract

The glenohumeral ligaments (GHLs) are the most important passive stabilizers of the shoulder joint. Recognition of acute and chronic glenohumeral ligamentous lesions is very important in the preoperative work-up of shoulder instability and trauma. This article describes and depicts the normal anatomy of the GHLs and their appearance during arthroscopy and on MR and computed tomography arthrography (CTA). Pathologic findings of the superior, middle, and inferior GHLs are described and illustrated with MR and CTA and their corresponding intraoperative arthroscopic images. MR arthrography (MRA) is useful for direct visualization of all GHLs including most lesions of their intra-articular portion and associated capsulolabral pathologies. Sprains, midsubstance tears, avulsion, or fibrous infiltration of the GHL can be identified on MRA images using fast spin-echo sequences with and without fat saturation in the three planes. Although CTA is reputed to better depict associated bony and cartilage lesions, CTA allows only indirect evaluation of the GHLs by outlining their contour or showing contrast penetration. Normal variants may create pitfalls that one should be aware of. Signs of GHL pathology on imaging include: discontinuity, nonvisualization, changes in signal intensity (on MRA), contrast extravasation, contour irregularity, thickening, or waviness.