Translations:Oberarmknochen/9/en
Aus Dornheim Anatomy
The bony socket (Cavitas glenoidalis) of the Articulatio humeri, a ball joint, is considerably smaller than the head of the humerus. The socket is enlarged by a fibrous cartilaginous joint lip, Labrum glenoidale. The surface of the Cavitas glenoidalis is approx. 6 sqcm. The weight of the upper extremity is about 4 kg. Since there are no stronger ligaments, the muscles surrounding the joint must secure it. This is known as a muscle-secured joint. The so-called "rotator cuff" is part of this muscular securing and especially strengthens the joint capsule.