Synonyms
Head of humerus, Tuberculum majus, Tuberculum minus, Epicondylus humeri radialis, Epicondylus humeri ulnaris, Fracture of humerus Medical: Humerus
Anatomy
The upper arm bone (humerus) is like all bones of the arm a tubular bone. Towards the shoulder joint, the humerus has a round head (caput humeri). This head of humerus is angled at approx.
130° to the shaft. Together with the shoulder blade, the head of humerus forms a part of the shoulder joint and is thus covered with a layer of cartilage tissue like all joints. Below the head of humerus there are two bone extractions (tuberculum majus and tuberculum minus), to which large muscle groups are attached.
The long biceps tendon runs in a groove (sulcus bicipitalis) between the bone extractions. Towards the elbow joint, the humerus spreads into its two joint rolls. The muscles of the forearm flexors and forearm extensors are attached to the side of the two joint rollers.
The flexors attach to the joint roller on the side of the radius (small finger side) at the so-called epicondylus humeri ulnaris. On the side of the spoke, the forearm extensors attach to the radial epicondylus humeri at the humerus.
- Tuberculum majus
- Biceps tendon above the bicipital sulcus
- Humeral head
- Upper arm bone shaft
Function
The humerus connects the shoulder joint with the elbow joint and thus with the forearm. At the shoulder, the humerus and the scapula form the shoulder joint, a so-called ball joint. At the elbow joint, the humerus forms the elbow joint with the ulna and radius, a hinge joint.
- Humerus (upper arm bone)
- Ulna (ulna)
- Spoke (radius)
Diseases of the upper arm bones
The most common disease of the humerus is tennis elbow (epicondylitis humeri radialis). Epicondylitis humeri radialis is a painful tendon insertion inflammation of the forearm extensor muscles. Inflammation of the forearm flexor muscles (epicondylitis humeri ulnaris), which is known as golfer’s elbow, is much less frequent.
There are also fractures of the humerus (humerus fracture). Fractures near the elbow, the so-called supracondylar humerus fracture, are particularly common in childhood. In older age, the fracture of the head of the humerus dominates.
Here, the joint head breaks into several fragments. Reconstruction is difficult. Fractures of the humerus are rather rare.
Another injury is dislocation of the shoulder (shoulder dislocation). In this case, the head of humerus leaves the socket and in most cases gets stuck under the coracoid process of the scapula.
