Give examples of the most common anatomical terms.

In order to correctly describe the shape and position of human body structure and their relationship,

It is necessary to formulate a recognized unified standard, that is, anatomical posture and orientation terms.

Beginners must master these basic knowledge accurately, so as to facilitate learning and communication and avoid misunderstanding.

Commonly used positioning terms:

1, up and down: according to the anatomical posture, the head is above and the feet are below.

In comparative anatomy or embryology, because of the relationship between animals and embryos, it is often changed to cranial side; Replace the bottom with the tail.

In limbs, proximal end and distal end are often used to describe the relationship between the parts, that is, the root near the trunk is the proximal end, while the relatively distant or distal part is the distal end.

2. Front and back: the former is the front and the back is the back. In comparative anatomy, it is usually called ventral and dorsal. Palmar side and dorsal side are commonly used when describing hands.

3. Inner and outer sides: based on the center line of the body, those close to the center line are the inner sides, and those relatively far from the center line are the outer sides. If the thumb of the hand is on the outside and the little finger is on the inside.

When describing the structure of the upper limb, because the ulna and radius of the forearm are juxtaposed, the ulna is inside and the radius is outside, so the ulna side can replace the inside and the radius side can replace the outside.

4. Inside and outside: used to indicate the relationship between some structures and cavities. What is inside the cavity is inside, and what is outside the cavity is outside. Pay attention to distinguish from inside and outside.

5. Shallow and deep: the part near the body surface is called shallow, and the relatively deep part inside is called deep.

Axis and surface of human body

(1) Axis: According to the anatomical posture, the human body can set three typical mutually perpendicular axes.

The first sagittal axis is the horizontal line in the front-back direction;

The coronal (frontal) axis 1 is the horizontal line in the left and right direction;

The vertical axis 1 is a vertical line perpendicular to the horizontal line.

Axis is often used to indicate the axis along which the displacement trajectory of bones moves when joints move.

(2) Plane: According to the axis, the human body or organ can be cut into different sections, and some structures can be observed from different angles.

Typical sections are: sagittal plane, taken along the sagittal axis. It is a longitudinal section that divides the human body into left and right parts. If this section just passes through the midline of the human body, it is called the median sagittal plane.

; The coronal plane or frontal plane is a section taken along the coronal axis. It is a longitudinal section that divides the human body into two parts, perpendicular to the sagittal plane and the horizontal plane.

The horizontal plane or horizontal plane is a horizontal plane cut along the horizontal line, which divides the human body into upper and lower parts and is perpendicular to the above two longitudinal planes.

It should be noted that the cross-section of an organ is generally not based on the long axis of the human body, but on its own long axis, that is, the cross-section taken along its long axis is called longitudinal cross-section, and the cross-section perpendicular to the long axis is called cross-section.

Flexion and extension of joints

In anatomical position, the forward motion of limbs in sagittal plane is called flexion, and the backward motion of limbs in sagittal plane is called extension.

For example, lifting the arm forward is the flexion of the shoulder joint, and moving backwards on the sagittal plane from the anatomical position is called the extension of the shoulder joint.

But with the pelvis as the boundary, the action in the sagittal plane is called flexion and extension.

For example, when we sit down, our pelvis and knees bend, our calves are lifted backward, our knees bend, and our knees stretch when we return to the anatomical position.

Of course, muscle exercise has many functions, such as

Neck flexion and extension, shoulder rotation, abduction, adduction, internal rotation, external rotation, spine flexion and extension, hip adduction and abduction, etc.