Difference Between Medial and Lateral

The key difference between medial and lateral is that medial is the term used to refer to structures close to the center or the median plane of an organism while lateral is the term used to refer to structures farther away from the median line.

Median plane or midline is the line drawn within the body in order to divide the body into right and left portions. In humans, midline runs down the center of the body from the head through the navel and going between the legs. Medial and lateral are two terms that are defined with respect to the midline of the body. Structures that are farther away from the midline are lateral while the structures that are closer to the midline are medial.

CONTENTS

1. Overview and Key Difference
2. What is Medial
3. What is Lateral
4. Similarities Between Medial and Lateral
5. Side by Side Comparison – Medial vs Lateral in Tabular Form
6. Summary

What is Medial?

Medial is the term that refers to the structures closer to the midline of the body. It is the opposite of the term lateral. Therefore, the medial side of something is always situated towards the center of the body.

For example, the medial ligament is a ligament located towards the midline of the body. Similarly, the medial side of the knee is the side closest to the other knee.

What is Lateral?

Lateral is the term that refers to structures located farther away from the midline of the body. It is the opposite of medial.

For example, when referring to the knee, lateral knee is the side of the knee farthest from the opposite knee.

What are the Similarities Between Medial and Lateral?

• Medial and lateral are two terms defined with respect to the midline of the body.
• Moreover, these terms have opposite meanings.

What is the Difference Between Medial and Lateral?

Medial is a term that describes the structures located towards the midline of the body while lateral is the term that describes the structures located away from the midline. Thus, this is the key difference between medial and lateral. Some examples of medial structures are medial knee, medial ligament, etc. Some examples of lateral structures are lateral knee, lateral ligament, etc.

The below infographic shows the difference between medial and lateral in tabular form.

Summary – Medial vs Lateral

Medial refers to something located towards the center of the body. The opposite term of this is the lateral. Hence, lateral refers to something that is located away from the center of the body. For example, the medial knee is the side of the knee which is closer to the other knee while the lateral knee is the side of the knee farthest from the opposite knee. Thus, this is a summary of the difference between medial and lateral.

Reference:

1. “Medial.” Wikipedia, Wikimedia Foundation, 29 Jan. 2018, Available here.
2. Jr, William C. Shiel. “Definition of Lateral.” MedicineNet, Available here.

Image Courtesy:

1. “Knee diagram” By Mysid – Vectorized and colorized in Inkscape, based on Image:Knee diagram.png (Public Domain) via Commons Wikimedia
2. “Medial Distal leg” By CFCF – Own work (CC BY-SA 3.0) via Commons Wikimedia