Anatomical terms of location: Encyclopedia II - Anatomical terms of location - Planes

Anatomical terms of location - Planes

Anatomical terms of location - General usage

Three basic reference planes are used in zoological anatomy. The sagittal plane divides the body into left and right portions. A coronal plane divides the body into dorsal and ventral portions. A transverse plane divides the body into cranial and caudal portions.

Anatomical terms of location - Usage in human anatomy

Sometimes the orientation of certain planes need to be distinguished, for instance in medical imaging techniques such as CT scans, MRI scans or PET scans. One imagines a human in anatomical position (standing, arms hanging down with palms to the front) and an X-Y-Z coordinate system with the X-Y plane parallel to the ground, the X-axis going front and back, the Y-axis passing left and right, and the Z-axis going up and down.

• A transverse (also known as axial or horizontal) plane is an X-Y plane, parallel to the ground, which (in humans) separates the superior from the inferior, or put another way, the head from the feet.
• A coronal (also known as frontal) plane is an Y-Z plane, perpendicular to the ground, which (in humans) separates the anterior from the posterior, the front from the back, the ventral from the dorsal.
• A sagittal plane is an X-Z plane, perpendicular to the ground and to the coronal plane, which separates left from right. The midsagittal plane is the specific sagittal plane that is exactly in the middle of the body.

Adapted from the Wikipedia article "Planes", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki