الهَيْكَل العظمي للإنسان - ٢ - كتاب في سبيل موسوعة علمية .. الدكتور أحمد ذكي

The human skeleton - 2 -

- There are two arches in the vertebral column

The child's vertebral column is straight, then it gradually curves with growth.

It has two outward arches, one at the chest, and the other
At the pelvis, and between them it curves inward. And all of them
Mild curves.

The thoracic arch gives the chest and its lungs a place in the heart
Wider.
The pelvic arch also gives the viscera a wider space.

- Ribs

We mentioned that there are 12 thoracic vertebrae, and 12 pairs of ribs emerge from them as well. In about 6 percent of people, these pairs reach 13 pairs. It gathers in front of the chest, and is fused with a bone known as the breastbone or sternum, which is in the middle of the chest from the front and descends from top to bottom. These vertebrae, ribs, and sternum make up the rib cage, in which the lungs and heart reside. This is a structure that resembles something like an external skeleton to preserve these dangerous organs that are important in life.

- There are two bone belts in the structure

This is in the sense of beautiful engineering planning. The first bony girdle is the pectoral girdle.

The second bony belt is the pelvic girdle.

- Chest belt

It is sometimes called the shoulder girdle. It consists of the back of the shoulder bone, which are two bones, right and left, and the front of it consists of the clavicle, which is also right and left. In each of the shoulder bones, there is a round hole occupied by the head of the arm bone, the humerus, which is like a ball. This gap, and this ball that rotates in it, are one of the most brilliant joints, and it is the one that gives permission to the arm. Right and left, to move this wide free movement.
The truth is that this bony belt, the pectoral belt, has a lot of freedom of movement. Unlike what we expected, it does not connect to the human skeleton in order to gain stability and dependence from it. This belt anchors him where he is and what is around him, which is in terms of preparing him for movement, and enjoying freedom of movement, (which is necessary for the movement of the arms that he carries), so that he rises from his place, and you raise from a muscle. Your arms up.

- Arms and hands

What we draw attention to is that there is one bone in the humerus, which articulates with the shoulder bone. Then the forearm: it has two bones, the ulna, which is the one that articulates, and the humerus, which is the one that ends at the bottom of the fingertips, and the second bone, which is the radius, which is the one that ends at the bottom of the thumb. The hand rotates. around its face, and the Kaaba rotates with it.

Another thing we draw attention to: placing the thumb opposite the other fingers of the hand. Thus, it was possible for a person to hold things, hold things in his hand, work, create, and acquire various skills using the tricks of artisans overflowing with thought.

- Pelvic belt

It's kind of like a chest belt. There is a difference between them, however.
It is called the pelvis because it creates the pelvis that contains whatever organs it contains. When it contains it, it carries it with what is above it as a burden. For this reason, he violated the thoracic girdle and was attached to the vertebral column, from which he derived help. The viscera in the pelvis and abdomen are connected by their own ligaments to the back chain.

In a pregnant woman, the pelvis carries her pregnancy. It is called the pelvis because it is like the pelvis that contains viscera that the abdomen does not contain. It is similar to the bottom of the abdomen, and for this reason it participates in carrying the entire human torso. The bones of the legs articulate with the pelvic bones. The pelvic girdle is also always prepared to receive shocks of movement, walking, running, and clashing.

The belt is bounded from behind by the five fused vertebrae called the pelvis, along with the other five known as the coccyx, on each side by the iliac bone, and in front of the pubic bone.

- The structure of the legs

. It is noted that the arm is a humerus and a forearm. And the leg is a thigh
And a leg.
The humerus and thigh have one bone, and the forearm, like the leg, has two bones.
It is also noted that the legs, because of their connection to the pelvic girdle, which is restricted by ties and weights, do not have the freedom of movement that the arms have.
The feet and fingers do not have the freedom of action or movement that the arms have.