The middle glenohumeral ligament (MGHL) serves as the primary constraint against anterior and posterior translation with the shoulder in 45° to 60° of abduction. The ligament inserts on the lesser tuberosity after originating from the anterior glenoid labrum. It is important during arthroscopic surgery to distinguish the MGHL running obliquely from the more horizontal (perpendicular to the glenoid) orientation of the subscapularis tendon (Figure 3). The ligament can present with different sizes and characteristics discussed in more detail in the section on the glenoid labrum.