Core Anatomy, Planes of the Body, and Directional Terms

Rectus abdominis

Located along the front of the abdomen, this is the most well-known abdominal. Often referred to as “six-pack”.

External abdominal oblique

Located on the side and front of the abdomen.

Internal abdominal oblique

Located under the external obliques, running in the opposite direction.

Transverse abdominis

Located under the obliques, it is the deepest of the abdominal muscles and wraps around your spine for protection and stability.

Coronal Plane

A vertical plane running from side to side divides the body or any of its parts into anterior and posterior portions. Also called as frontal plane.

Sagittal Plane

A vertical plane running from front to back divides the body or any of its parts into right and left sides. Also called as lateral plane.

Transverse Plane

A horizontal plane that divides the body or any of its parts into upper and lower parts. Also called as axial plane.

Flexion and Extension

Movements that occur in the sagittal plane.

Abduction and Aduction

Movements that occur in the frontal plane.

Directional terms of location

Vital to understanding and using anatomy. They help avoid any ambiguity that can arise when describing the location of structures.

Medial

Towards the midline.

Lateral

Away from the midline.

Anterior

Also called “ventral”, refers to the front.

Posterior

Also called “dorsal”, refers to the back.

Superior

Also called as “cranial”, means higher.

Inferior

Also called as “caudal”, means lower.

Proximal

A structure that has a beginning and an end and is closer to the center or point of reference.

Distal

A structure that has a beginning and an end and is farther to the center or point of reference.