Corpus: Glenohumeral ligaments

The glenohumeral ligaments arise from the fibers of the glenoid labrum at the supraglenoid tubercle of the scapula and extend as part of the joint capsule to the anatomical neck of the humerus. They are characterized as folds on the inner side of the joint capsule. Three parts are distinguished:

• Superior glenohumeral ligament (SGHL): Narrow, thin ligament that, together with the coracohumeral ligament, stabilizes the adducted or neutrally positioned arm and the external rotators in the adducted position. It reinforces the rotator interval of the shoulder joint.
• Middle glenohumeral ligament (MGHL): Usually well-developed with significant variability. It stabilizes the humeral head against anterior translation, especially in mid-abduction.
• Inferior glenohumeral ligament (IGHL): Most strongly developed (highest tensile strength). It has two reins, an anterior and a posterior, between which the capsule forms the axillary recess. Its effect increases with increasing abduction in the shoulder joint, resisting anterior, posterior, and inferior translation.

Additional reinforcements of the joint capsule include:

• Spiral glenohumeral ligament
• Coracoglenoidal ligament

Partial aplasia of the glenoid labrum is often associated with a cord-like thickening of the medial glenohumeral ligament (Buford complex). This normal variant can be mistaken for labral injuries arthroscopically or in imaging studies.

In shoulder dislocation, the glenoid labrum may tear off along with the anterior part of the inferior glenohumeral ligament from the rim of the glenoid cavity. This is known as a Bankart lesion.

Injuries to the SGHL form the basis of the so-called Pulley lesion. A bony avulsion of the IGHL from the humerus is referred to as a HAGL lesion, and an avulsion from the glenoid as a GAGL lesion.