Anatomical Directional Terms and Body Planes

Health Science 20

Anatomical Directions Terms and Body Planes

• Anatomical directional terms are like the directions on a compass

• Used to describe the locations of structures in relation to other structures or locations in the body.

• Provides a common method of communication that helps to avoid confusion when identifying structures

• Each directional term often has a counterpart (opposite meaning)

Anatomical Body Planes

• Imagine dissecting a person with imaginary vertical and horizontal planes.

Sagittal Plane (Lateral 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

Coronal Plane (Frontal Plane)

• Imagine a vertical plane that runs through the center of your body from side to side

• Divides the body into front (anterior) and back (posterior) regions

Transverse Plane

• Imagine a horizontal plane that runs through the midsection of your body

• Divides the body into upper (superior) and lower (inferior) regions.

Anatomical Directional Terms

Anterior/Posterior

• Anterior – in front of; front• Posterior – after, behind, following, toward

the rear

Distal/Proximal

• Distal – away from; farther from the origin

• Proximal – near; closer to the origin

Dorsal/Ventral

• Dorsal – near the upper surface; toward the back

• Ventral – toward the bottom; toward the belly

Superior/Inferior

• Superior – above; over• Inferior – below; under

Lateral/Medial

• Lateral – toward the side; away from the midline

• Medial – toward the midline; middle; away from the side

Body Cavities

Body Cavities

• A cavity is an open region within something

• There are 5 cavities in the body:– Cranial– Spinal– Thoracic– Abdominal– Pelvic

Cranial Cavity• Aka. Intracranial space• In the dorsal side of the

body• Space formed inside the skill• The brain occupies the

cranial cavity• Lined by the meninges

which contain cerebrospinal fluid to cushion blows

Spinal Cavity• Aka. Intracranial space• In the dorsal side of the

body• Contains the vertebrae

and the spinal cord

Thoracic Cavity• Aka. Chest cavity• Ventral side of body• Protected by the

thoracic wall (rib cage and associated skin, muscle, and fascia)

• Contains heart and lungs

Abdominal Cavity

• Largest body cavity• Located inferior to

the thoracic cavity and superior to the pelvic cavity

• Contains digestive organs

Pelvic Cavity

• Primarily contains reproductive organs, the urinary bladder, the pelvic colon, and the rectum