Glenoid Labrum N139

Study Notes

The glenoid labrum is an accessory structure that enhances the total available articular surface of the glenoid fossa by approximately 50%.
It is composed of densely packed fibrous connective tissue covered by a fine superficial mesh consistent with cartilaginous tissue, with fibrocartilage at the attachment of the labrum to the periphery of the fossa.
The glenoid labrum performs a variety of functions, including resistance to humeral head translations, protection of the bony edges of the labrum, reduction of joint friction, and dissipation of joint contact forces.
The glenoid labrum serves as the attachment site for the glenohumeral ligaments and the tendon of the long head of the biceps brachii.
The glenoid labrum deepens the concavity of the fossa, increases contact area with the humeral head, and helps stabilize the joint.
The superior part of the glenoid labrum is only loosely attached to the adjacent glenoid rim, and the biceps tendon can partially detach the superior labrum from its near-12 o'clock position on the glenoid rim.
The relatively high incidence of superior labral tears in throwing athletes is related to the forces produced within the biceps during this activity.
Lesions or detachments of the glenoid labrum are also common along the anterior-inferior rim of the glenoid fossa.
Conservative management of a detached or torn glenoid labrum is often unsuccessful, and surgical repair is often required, followed by a specific postoperative rehabilitation program.
Pathomechanics may predispose the throwing athlete to anterior instability and further associated stress.