The meaning of humerus

The meaning of humerus: Humerus is the strongest bone in the upper limb. The upper end forms the shoulder joint with the scapula, and the lower end forms the elbow joint with the radius and ulna.

Extended data

anatomical structure

The upper end of humerus consists of humeral head, humeral neck, large tubercle and small tubercle. Spherical humeral head and glenoid joint of scapula. The annular shallow groove around the humeral head separates the slightly thinner part between the humeral head and the large and small tubercles, which is called the anatomical neck of humerus. The joints of the head, neck and humerus are large and small nodules, which provide attachment points and levers for some scapular humerus muscles. The greater tubercle is located outside the humerus, and the smaller tubercle is located in front of the humerus. Internodular sulcus (biceps brachii sulcus) separates large and small nodules. The surgical neck of humerus is a slightly thinner part of the distal end of the large and small nodules, which serves as the ridge of the large and small nodules under the two nodules and connects with the intertubercular groove on the side. Surgical neck is a common fracture site of humerus.

Features and auxiliary structures

The humeral body has two remarkable features:

1, deltoid muscle tuberosity, located on the outside, is the attachment point of deltoid muscle; The oblique groove of radial nerve is located in the back, and the radial nerve and deep brachial artery pass through it. The deep brachial artery first passes between the medial head and the long head of triceps brachii, and then passes through the lateral head of triceps brachii.

2. The lower end of the humerus is wide, with sharp medial and lateral supracondylar ridges, and then stops at the distal end, especially the epicondyle extends to the lateral side, providing attachment points for muscles. The distal end of the humerus, including the epicondyle, trochlea, capitulum humeri, olecranon fossa, coronary fossa and radial fossa, constitutes the humeral condyle. This condyle has two articular surfaces: the lateral head, which is related to the radial head; The medial sideslip vehicle is related to the proximal ulna (trochlear notch). Above the pulley, the coronoid fossa is in front to accommodate the coronoid fossa of ulna when the elbow joint is fully flexed, and the olecranon fossa of ulna is behind, and the olecranon of ulna is embedded when the elbow joint is fully straightened. There is a shallow radial fossa above the capitulum, and the leading edge of the radial head meets this fossa when the forearm is fully flexed.