Finally, there is the inferior glenohumeral ligament, which is the most constant ligament. It is the most important for anterior stability, and is the most commonly torn. It has an anterior band and a less important, less significant, posterior band. We can see these three ligaments any time there is fluid in the joint. Without fluid in the joint, they all compress together, lay tightly on one another, and are almost impossible to see.
Instability is quite common in the anterior direction.
It's not nearly as common posteriorly, but it is still seen frequently, especially associated with ganglions posteriorly. The labrum itself can tear, just as a meniscus can tear. More frequently, though, it detaches or tears off from its bony attachment. It can be frayed, degenerated, fibrillated, irregular, and it can have mucoid or myxoid degeneration just like other areas of the body. Figure 29 Cutting through the glenohumeral ligaments on axial images can be somewhat confusing at first.