The human body consists of two seemingly symmetrical halves, which also contain pairs of seemingly symmetrical organs bilaterally. The imaginary vertical line (plane) that divides the body into the left and right side, or front and back, is actually an anatomical border of the body’s planes.
Each of the anatomical planes of the body has a specific position and governs specific motions. With their help, we can analyze and define the movements of the human body more easily, which is why these are also called the planes of movement. Additionally, the anatomical planes help us determine the position of the organs in the body.
What Are the Other Major Anatomical Planes Of the Human Body?
The other main anatomical planes of our body are the sagittal plane, frontal (coronal) plane, and transverse plane.
These imagined lines create symmetrical maps of the human body for more convenient analysis and definition of the bodily movements, regarding direction and position.
Sagittal (Lateral) Plane
The vertical anatomical border line that divides our body into the left and right side is called a sagittal plane.
What Does ‘Sagittal’ Mean?
The name of the sagittal plane is derived from the Latin word sagitta, which means an arrow. Hence, when we talk about it, we refer to a vertically pointed axis that divides our body into several flat surfaces or areas, in this way defining the positions of our movements.
Try to imagine a person in an upright position. Now, imagine a long, vertical arrow pointed downward, passing through the center of the body from head to toe. It helps us visualize how the body is divided into two symmetrical halves, right? Yes, that arrow is the sagittal plane of the human body.
The Role Of the Sagittal Anatomical Plane
Since the motions of the human body can be classified according to the anatomical plane in which they occur, the sagittal plane is the field where the forward and backward motions of our body occur. Such motions are the movements of flexion and extension.
The examples of flexion and extension movements include: bending of the neck or the body forward and backward, sit-ups, etc.
What Are The Sub-planes Of The Sagittal Plane?
The sagittal plane is further divided into two sub-planes: midsagittal and parasagittal plane.
Midsagittal Plane
This anatomical plane is a subplane of the sagittal plane. It is projected exactly in the midline of the human body and passes along the midline structures, like through the spinal cord, for example.
The mid-sagittal plane vertically divides the body into two equal parts – left and right from head to toe. Hence, it includes half of the brain, half of the face, the thorax (the chest), the abdomen (the stomach), one arm, and one leg in its field.
Starting from the head, the midsagittal plane passes through the following bones of the skull:
- Frontal bone
- Parietal bone
- Occipital bone
- Nasal bones
- Maxillary bone
- Mandible bone
Furthermore, the midsagittal plane divides the brain into the left and right hemisphere, separates the nasal cavity, the tongue, and the throat (the pharynx and the larynx).
It continues to run along the vertebrae, also dividing it into two halves, and goes on further through the spinal cord.
When the midsagittal anatomical plane comes to the thorax, it loses its symmetrical division due to the lack of symmetry of this part of the body. This is also true with this imaginary division in the case of the stomach, because the pancreas, stomach, appendix, liver, and gallbladder are not all located in a single part of the midsection.
However, located in the lower part, under the abdomen, both the male and female reproductive organs are symmetrically divided into a left and a right side by the midsagittal plane.
Parasagittal Plane
The parasagittal plane is parallel to the sagittal plane, but it does not pass directly in the midsection of the human body, which is why it divides it into two unequal parts.
The name of this sub-plane of the sagittal plane is of Greek origin. Namely, the prefix / para- / in Greek means ‘next to’. And this is exactly where the parasagittal plane is projected in the body – next to, or parallel to the sagittal plane.
This is the reason why it’s often used synonymously with the sagittal plane while describing the vertical division that creates the left and the right side of our body.
What Is The Difference Between The Sagittal And The Midsagittal Anatomical Plane?
While the sagittal plane divides the human body into two seemingly symmetrical parts, the midsagittal plane runs through the midsection of the body, creating two perfectly symmetrical parts – left and right.
Also, the sagittal plane is not limited to a specific portion of the body, whereas the midsagittal plane is strictly projected in the middle part of the human body, dividing it into two equal halves. This is the main difference between the sagittal and midsagittal planes.
What Is The Difference Between The Sagittal And The Parasagittal Anatomical Plane?
Any anatomical plane which runs parallel to the sagittal plane is called a parasagittal plane. The main difference is that the latter does not pass directly in the midline section of the human body, so it divides it into two unequal halves.
Which Are the Other Anatomical Planes Of the Body?
As previously mentioned, there are three anatomical planes of the human body. Apart from the sagittal anatomical plane, there are also the frontal (coronal) and transverse planes.
Frontal (Coronal) Plane
The frontal (coronal) plane vertically divides the human body into the front (anterior) and back (posterior) part. This plane can be imagined as a vertical plane that runs through the center of your body from side to side.
Hence, the motions which occur in the area of this plane are side-to-side movements, such as jumping jacks, side leg lifts, etc. In more specific words, these motions are labeled as abduction, adduction, and circumduction.
Transverse (Axial) Plane
The transverse anatomical plane is the ‘arrow’ which runs horizontally through the midsection of the human body. This horizontal plane divides our body into upper (superior) and lower (inferior) parts.
Hence, the transverse plane is the field where the rotational movements of the body occur. The rotation of our head, as well as the upper and the lower part of the body, occur in this anatomical plane.
How Can We Improve Our Movements In The Three Dimensional World We Live In?
Living in a three-dimensional world, our bodies also need to be able to properly move in all dimensions.
Every day we push, pull, flex, extend, squat, lunge, bend, and twist, without being aware that these movements are projected through the imagined three-dimensional anatomical planes of our bodies.
However, any improper movement can lead to chronic pain, as well as serious bodily injuries.
By working on the improvement of our three-dimensional movements, we can avoid those risks, and also enjoy a healthier life. All daily activities would be easier with more balanced and coordinated movements.
We can do it simply by following the patterns projected by the anatomical planes of our bodies.
For instance, since the sagittal plane is the area concerned with forward and backward movements, we can choose physical exercises that have a repetitive pattern of these types of movements.
A good example of a sagittal plane exercise would be the back squat. With this exercise, the section of the body below its middle is in motion, performing flexion when lowering down, and extension while standing up.
During the process of flexion and extension, i.e. the exercise, the knees remain parallel to the imagined sagittal plane, which divides our body into a left and right half.
In a similar manner, we can choose physical exercises that activate movements performed within the other anatomical planes of the body. We can choose exercises performed with side-to-side movements for a more balanced frontal plane, such as lateral raise of extremities or side bend.
As for the balancing of movements occurring in the transverse anatomical plane of the body, the exercises with rotation and twisting would be the best option.
To Sum Up
The anatomical planes of the human body serve as a map of the movements of the body and its symmetry. They present directional terms used to describe various parts and directions of the body, as well as the position of the organs.
There are three main anatomical planes of the human body: sagittal, frontal (coronal), and transverse planes. The sagittal plane is the imagined vertical arrow that divides the human body into not-always-symmetrical halves.
Yet, when it reaches the midsection of the body, the sagittal plane becomes midsagittal and more symmetrical, due to the bodily symmetry at that part.
After it passes the midsection, the sagittal plane becomes a parasagittal plane, i.e. an anatomical plane which passes everywhere but in the middle section of the body.
While the sagittal plane divides the body into left and right portions, the frontal (or coronal) plane divides it into the back and front part. On the other hand, the transverse anatomical plane of the body divides it horizontally into upper (superior) and lower (inferior) parts.
By analyzing the movements of the human body and understanding its division into the three anatomical planes and their subdivisions, we can prevent injuries and feel more balanced.
Fun Facts
Did you know?
- With the help of the anatomical planes, we can describe any part of the body and even the entire body.
- Just like maps have their East, West, North, and South sides, the anatomical planes of the body have their planes in order to describe the parts of the body (or the organs) in relation to the other parts of the body.
- Each of the anatomical planes of the human body has its directional counterpart: left-right, front-back, up-down.
- When the ancient physicians were analyzing the body and naming all its parts, they were trying to give them names which would be easy (and logical) to remember. Hence, they named all anatomical concepts according to the position and appearance in the language widely used at that time – Latin.
- Sit-ups, squats, lunges, and crunches, are the type of motions which occur in the sagittal plane.
- The flexing of your biceps also occurs within the sagittal plane.
- The anatomical planes of the body help us understand the three-dimensional structure of our body.
- Also, the anatomical planes of the body lie at right angles with each other.
- The CT scans present a typical transverse section of the body.
- The frontal planes practically divide the head into a face (frontal region) and the back of the head (occipital region).