Directions and planes

There are three common paired directions and three orthogonal planes used to describe locations and views in anatomy.

The central axis is a line that runs through the  line of gravity.

Anatomical terms of location

A preview of the principal directions (or more formally, terms of location)....

Lateral is the direction away from the axis, and medial (not shown) is toward the axis in the coronal plane.

Anterior is towards the front of the body, and posterior is toward the back of the body

Superior is upward, toward the head, and inferior is downward, toward the toes.

Anterior and posterior

Anterior refers to the front or forward portion of the body. Posterior means at or toward the back. An anterior view of the body is the front and posterior, the back. Adverbs: anteriorly and posteriorly.

Medial and lateral

Medial means closer to the plane of symmetry of the body (think median).  Lateral is a direction away from the plane of symmetry of the body, off to the side (think football).
Adverbs: medially, laterally.

Lateral view of head with overlayed angiogram.

Superior and inferior

The superior direction is upward, toward the head. The inferior direction is downward, toward the feet. Adverbs: superiorly and inferiorly.

The shoulders are superior to the hips. The hips are inferior to the head.

Sometimes cephalid (head) is used for superior. Caudal (tail) can be used for inferior.

Sagittal plane

The sagittal plane slices the body into a left and a right portion. The sagittal plane is oriented like an arrow strikes the body in ancient combat.

Sagitta means arrow in Latin (think Sagittarius, the archer).  The sagittal plane can move medially and laterally.

Coronal plane

The coronal plane slices the body into anterior and posterior portions. Corona means crown in Latin.  The coronal plane can move anteriorly and posteriorly.

Coronal MRI of the knee (anterior view).

Transverse plane

The transverse plane slices the body into superior and inferior portions. The transverse plane can move superiorly and inferiorly.

Recap

There are three common paired directions and three orthogonal planes used to describe locations and views in anatomy. The central axis is a line that runs through the  line of gravity. Other key paired terms are

ipsilateral - contralateral
superficial - deep
proximal - distal

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