Corpus: Glenoid cavity

The glenoid cavity, or simply the glenoid, refers to the relatively flat articular socket of the shoulder joint that makes contact with the humerus.

Just below the acromion, the flat scapula thickens to form the scapular neck, laterally proceeding to form the glenoid cavity. Its slightly concave surface has the shape of an inverted comma. The glenoid is separated from the base of the acromion or the spine of scapula by the spinoglenoid notch.

The glenoid provides only a relatively small, cartilage-covered articular surface of an oval longitudinal cross-section. Therefore, it is enlarged by a fibrocartilaginous ring attached to its outer edge, known as the glenoid labrum. The total surface area of the glenoid is about three to four times smaller than that of the humeral head. The surface of the glenoid is almost perpendicular to the plane of the scapula. At its cranial tip lies the supraglenoid tubercle, which marks the origin of the long head of the biceps tendon. At its caudal end is the infraglenoid tubercle, marking the origin of the long head of the triceps tendon. On the anterior edge, the glenoid has a small notch (glenoid notch).