Lesson 1, Topic 1
In Progress

04-Anatomical Directions

March 28, 2021

Directional terms are useful in describing relative positions of body parts and are best thought of as opposite pairs:

    1. Superior and inferior—superior, meaning toward the head, upper, or above, and inferior, meaning toward the feet, lower, or below
    2. Anterior and posterior—anterior refers to the front or in front of and is the same as ventral in humans, whereas posterior refers to the back or in back of, which is the same as dorsal in humans
    3. Medial and lateral—medial means toward the midline of a structure and lateral means away from the midline or toward the side of a structure
    4. Proximal and distal—proximal is defined as toward or nearest the trunk, or nearest the point of origin of a structure; distal is defined as away from or farthest from the trunk, or farthest from a structure’s point of origin
    5. Superficial and deep—superficial, meaning nearer the body surface, and deep, meaning farther away from the body surface

All of these directions can be indicated on an anatomical compass rosette, which is an illustration using abbreviated directional terms.

Anatomical compass rosette
To make the reading of anatomical figures a little easier for you, we have used an anatomical compass rosette throughout this book. On many figures, you will see a small compass rosette like you might see on a geographical map. Instead of being labeled N, S, E, or W, the anatomical compass rosette is labeled with abbreviated anatomical directions.

For example, in Figure 1-3 (p. 7), the rosette is labeled S (for superior) on top and I (for inferior) on the bottom. Notice that in Figure 1-3 the rosette shows R (right) on the subject’s right—not your right. Now look at the rosettes in Figure 1-4 and compare them to the body positions shown.

 

Here are the directional abbreviations used with the rosettes in this book: