Anatomical Directional Terms and Body Planes

Anatomical Planes
Juan Pablo Bouza / Wikimedia Commons / CC BY-SA 3.0

Anatomical Directional Terms and Body Planes

Anatomical directional terms are like the directions on a compass rose of a map. Like the directions, North, South, East and West, they can be used to describe the locations of structures in relation to other structures or locations in the body. This is particularly useful when studying anatomy as it provides a common method of communication that helps to avoid confusion when identifying structures.

Also as with a compass rose, each directional term often has a counterpart with converse or opposite meaning. These terms are very useful when describing the locations of structures to be studied in dissections.

Anatomical directional terms can also be applied to the planes of the body. Body planes are used to describe specific sections or regions of the body. Below are examples of some commonly used anatomical directional terms and planes of the body.

Anatomical Directional Terms:

Anterior: In front of, front
Posterior: After, behind, following, toward the rear

Distal: Away from, farther from the origin
Proximal: Near, closer to the origin

Dorsal: Near the upper surface, toward the back
Ventral: Toward the bottom, toward the belly

Superior: Above, over
Inferior: Below, under

Lateral: Toward the side, away from the mid-line
Medial: Toward the mid-line, middle, away from the side

Rostral: Toward the front
Caudal: Toward the back, toward the tail

Bilateral: Involving both sides of the body
Unilateral: Involving one side of the body

Ipsilateral: On the same side of the body
Contralateral: On opposite sides of the body

Parietal: Relating to a body cavity wall
Visceral: Relating to organs within body cavities

Axial: Around a central axis
Intermediate: Between two structures

Anatomical Body Planes:

Imagine a person standing in an upright position. Now imagine dissecting this person with imaginary vertical and horizontal planes. This is the best way to describe anatomical planes. Anatomical planes can be used to describe any body part or an entire body. (View a body plane image.)

Lateral Plane or Sagittal Plane: Imagine a vertical plane that runs through your body from front to back or back to front. This plane divides the body into right and left regions.

  • Median or Midsagittal Plane: Sagittal plane that divides the body into equal right and left regions.
  • Parasagittal Plane: Sagittal plane that divides the body into unequal right and left regions.

Frontal Plane or Coronal Plane: Imagine a vertical plane that runs through the center of your body from side to side. This plane divides the body into front (anterior) and back (posterior) regions.

Transverse Plane: Imagine a horizontal plane that runs through the midsection of your body. This plane divides the body into upper (superior) and lower (inferior) regions.

Anatomical Terms: Examples

Some anatomical structures contain anatomical terms in their names that help identify their position in relation to other body structures or divisions within the same structure. Some examples include the anterior and posterior pituitary, superior and inferior venae cavae, the median cerebral artery, and the axial skeleton.

Affixes (word parts that are attached to base words) are also useful in describing the position of anatomical structures.

These prefixes and suffixes give us hints about the locations of body structures. For example, the prefix (para-) means near or within. The parathyroid glands are located on the posterior side of the thyroid. The prefix (epi-) means upper or outermost. The epidermis is the outermost skin layer. The prefix (ad-) means near, next to, or toward. The adrenal glands are located atop the kidneys.

Anatomical Terms: Resources

Understanding anatomical directional terms and body planes will make it easier to study anatomy. It will help you to be able to visualize positional and spacial locations of structures and navigate directionally from one area to another. Another strategy that can be employed to help you visualize anatomical structures and their positions is to use study aids such as anatomy coloring books and flash cards.

It may seem a bit juvenile, but coloring books and review cards actually help you to visually comprehend the information.