Translations:Schultergürtel/13/en

The Angulus acromii is an easily palpable bone point that marks the point where the lateral margin of the Acromion merges into the Spina scapulae. The acetabulum, Cavitas glenoidalis (11), is located at Angulus lateralis . At their upper margin a small hump is visible, the Tuberculum supraglenoidale (12). Below the cavitas is the Tuberculum infraglenoidale (13). After Cavitas glenoidalis the neck of Scapula, Collum scapulae is located. Above the cavitas glenoidalis rises the raven beak process, processus coracoideus (14). It bends at right angles to lateroventral and ends flattened. Together with the acromion it protects the underlying joint. Medially from the base of the processus coracoideus there is an incision in the margo superior, incisura scapulae (15). The bony socket Cavitas glenoidalis (11) of the Articulatio humeri, a ball joint, is significantly 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 why we speak of a muscle-secured joint. The so-called "rotator cuff" is part of this muscular securing and especially strengthens the joint capsule.