Identifying the gleno humeral ligaments on MRI can be challenging as they are small and on lower field strength scanners there is inadequate resolution to see them properly.
However if we understand the anatomy of the ligaments it becomes easier to know where to look, even if we cant directly identify the ligament. This post is an adaptation of a talk given at Radiology Asia in Singapore titled Gleno Humeral Ligaments made Easy…er.
|Which Ligaments are we talking about?
There are 3 Glenohumeral ligaments.
1. SGHL: Superior Gleno Humeral Ligament
2. MGHL: Middle Gleno Humeral Ligament
3. IGHL: Inferior Gleno Humeral Ligament
The Coraco Humeral Ligament (CHL) is extra capsular and is not part of the glenohumeral ligaments but we will also look at as it helps to identify the SGHL and it also fuses with the joint capsule at the rotator interval.
|1. How to Identify the Coraco Humeral Ligament: Start with the Coracoid Process
|2. How to find the Superior Gleno Humeral Ligament: When an Octopus meets the ligaments.
The ligaments arise in an orderly fashion and using analogies often helps to understand anatomy. On sagittal scans the ligaments have the appearance of tentacles of an octopus radiating from the biceps insertion on the supra glenoid tubercle.
Continuing to scroll laterally, the CHL ( blue arrow) and the SGHL ( Pink arrow) start to approximate each other and fuse with the capsule ( yellow arrow) to form one structure, the Rotator Interval Capsule..
|Superior Gleno Humeral Ligament Axial Scans