Glenoid labrum

The glenoid labrum, including the limbus, labrum or cartilage lip is a 3-4 mm wide, beaded frame of the joint socket ( glenoid cavity, even for a short glenoid ) of the shoulder blade ( shoulder joint ).

The still popular opinion, the glenoid labrum consists entirely of fibrous cartilage is refuted since the year 1962. Faserknorpeliges tissue is found only in a narrow transition zone at the base of the bone, otherwise there is the glenoid labrum from predominantly circularly arranged collagen fibers. It is in the rear lower ( posteroinferior ) part very firm, but connected in the front upper part ( anterosuperior ) movable with the bones of the joint socket. On the other hand, the labrum is also the front ( anterior) over directly into the joint capsule and surrounding ligaments and tendons. The glenoid labrum is therefore no uniform morphological structure and consists of different zones, it also has anatomical variants.

Also located on the upper ( superior / cranial ) moving part of the approach of the long biceps tendon (LBS ). The transition of the long biceps tendon in the upper glenoid labrum is biceps ( long ) anchor, labrum - biceps ( long ) complex labral LBS complex or SLAP complex called ( SLAP is an acronym for Superiores Labrum Anterior and Posterior ).

Function

The glenoid labrum increases the bony articular surface of the glenoid by about a third and by its wedge-shaped structure, it causes an additional deepening of the glenoid. Thus, it provides a better coverage of the humeral head, and it increases the compliance of the joint partners involved in the edge of the joint, resulting in a more favorable stress distribution, a better centering of the humeral head and a stabilization of the shoulder joint results. In particular, the SLAP complex for the stability of the joint is of great importance, while the long biceps tendon plays an important role.

Damage

Depending on the situation following damage to the labrum glenoid be distinguished:

In the upper part:

  • SLAP lesion

In the front region:

  • Andrews lesion
  • Bankart lesion
  • ALPSA lesion
  • GLAD lesion

In the rear section:

  • Bennett lesion
  • "Reversed " Bankart lesion
  • Walch - lesion
Tissue (biology) Anatomy Digital Object Identifier
481355
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