Normal MR imaging anatomy of the rotator cuff tendons, glenoid fossa, labrum, and ligaments of the shoulder.

The shoulder is commonly imaged using MR imaging, with or without intraarticular contrast medium. Some anatomic structures, such as the rotator cuff tendons and bony components, can be assessed without arthrographic technique, whereas the glenohumeral ligaments and labrum require arthrographic technique for more accurate assessment. In either case, an understanding of the normal anatomy of the shoulder with regard to bony and soft tissue structures is essential for MR imaging interpretation. In this article we discuss normal anatomy and variations of the glenohumeral joint(bone and soft tissues), rotator cuff tendons, and coracoacromial arch.