Drawing method of human structure spine

The spine (spinal column) consists of vertebrae and fibrocartilage intervertebral discs (that is, lumbar intervertebral discs that are always protruding). Can provide support for the head and chest. The spine gets thicker as it goes down, because the lower vertebrae bear more and more weight. The human body has 24 movable vertebrae (or true vertebrae); Nine fixed vertebrae (or pseudocolumns).

The sequence is as follows: 7 cervical vertebrae, 0/2 thoracic vertebrae, 5 lumbar vertebrae, 5 fused sacral vertebrae (forming sacrum) and 4 semi-fused coccyx (forming coccyx).

Because the human body is often in an upright position, in order to balance all parts of the body, the spine forms four physiological radians. This radian can also make the human body save muscle energy consumption to the maximum extent in a balanced state.

The cervical spine and lumbar spine form two radians that protrude forward; Thoracic vertebra, sacrum and coccyx form two kyphosis radians, and the radians of sacrum and coccyx are also called "pelvic curve".

Viewed from the side, along the spinous process of the spine, the arc anterior concavity is more obvious than the arc posterior concavity.

The thoracic vertebra is an integral part of the thoracic cavity, and the sacral vertebra fixed between two pelvic bones forms the back side of the pelvic belt, providing support for the upper movable vertebra.

The cervical vertebra supports the head; The lumbar spine supports the chest and head and neck. The skull is located at the top of the spine; The top of the spine is just behind the mouth.

When the human body is standing, the muscles on both sides of the midline of the back form a groove, which is called the spinal groove. The terminal point of spinous process is located at the groove bottom of spinal sulcus.