The glenohumeral joint is a synovial-lined ball-in-socket joint that has the greatest range of motion of any joint in the human body. The glenohumeral joint is the most commonly dislocated joint, attributed to the much larger articular surface area of the humeral head and the smaller, shallow glenoid fossa. The glenoid labrum is a fibrocartilaginous cuff surrounding the glenoid fossa. The labrum deepens the fossa and increases the articular surface area of the glenoid. The osseous rim of the glenoid and the fibrocartilaginous labrum are sites of attachment for the glenohumeral ligaments and long head biceps tendon, which can be injured individually or in tandem.
Glenohumeral stability is provided by dynamic and static “restraints”. Dynamic restraints include the rotator cuff and the long head biceps brachii tendon. Static restraints include the glenohumeral ligaments, glenohumeral joint capsule (including the rotator cuff interval capsule), the coracohumeral ligament, the glenoid labrum, and the bones. The attachments of the glenohumeral ligaments and the long head biceps anchor to the labrum are stronger than the attachment of the labrum to the glenoid rim. Therefore, the glenoid labrum is commonly torn or avulsed when excessive force is applied to a glenohumeral ligament or the long head biceps.These injuries have classic appearances, and are associated with multiple acronyms (such as ALPSA and SLAP) and eponyms (like the Hill Sachs deformity).
1-There are three glenohumeral ligament which are the superior, middle and inferior .
2-The inferior glenohumeral ligament is seen in the coronal view of the shoulder joint with inferior labrum.
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| Lateral view of the shoulder with the humerus removed demonstrates the restraints of the glenohumeral joint. Inferior glenohumeral ligament (IGHL), middle glenohumeral ligament (MGHL), superior glenohumeral ligament (SGHL), long head of the biceps (LHB), and coracohumeral ligament (CHL). The supraspinatus (Sup), infraspinatus (Is), subscapularis (Sub), and teres minor (Tm), and coracoacromial ligament (CAL) are indicated. |
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| A fat suppressed oblique sagittal T1-weighted MR arthrogram image, demonstrating the anterior and posterior bands of the inferior glenohumeral ligament (arrows). |
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| A fat suppressed oblique sagittal T1-weighted MR arthrogram image demonstrating the middle glenohumeral ligament (arrow). |
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| A fat suppressed axial T1-weighted MR arthrogram image demonstrates the superior glenohumeral ligament (arrow), the glenoid labrum (arrowhead), the long head biceps tendon (short arrow), and the coracohumeral ligament (curved arrow). |
3-Middle glenohumeral ligament is present between subscapularis and anterior labrum(seen in axial view).
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| Axial T2 SPAIR fat suppressed sequence showing normal MGHL. |
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