Terms Related To Other Anatomic Planes

The midsagittal plane is not the only type of anatomic plane that helps define the various terms of relative body position. Another is called a coronal (kor-OHN-al) plane. This plane is named after the coronal suture (Figure 2.6). A coronal plane is one passed down through the body in the direction of the coronal suture, which looks like a ''seam'' or crack made by a heavy ''crown'' (coron) smashed down hard upon a prince's head! A coronal plane is

Fig. 2.5 Some important terms associated with the midsagittal plane (body midline).

alternately called a frontal plane, because it subdivides the body into both front and back portions.

By passing a coronal (frontal) plane between the right eye and right ear, for instance, we can say that the right eye is anterior (an-TEER-ee-er) to the right ear. This translates to mean ''one that'' (-or) is ''in the front'' (anteri). To be sure, the right eye is more ''in the front'' (anterior) compared to the right ear. But it is also more ventral (VEN-tral) or ''pertaining to'' (-al) the ''belly'' (ventr). For a human being standing in the anatomic position, then, the right eye is anterior or ventral to the right ear, because it is both in front of it, and closer to the belly-side of the body.

Conversely, the right ear is both posterior (pahs-TEER-ee-er) and dorsal (DOR-sal) to the right eye. In Common English, this means that the right ear is both ''behind'' (posteri) and in ''back'' (dors) of the right eye.

Fig. 2.6 Anatomic terms related to the coronal plane.

Transverse planes and cross-sections

A third type of anatomic plane is called a transverse (tranz-VERS) or horizontal plane. This anatomic plane is ''turned'' (vers) and passed ''across'' or ''through'' (trans-) the body in a ''horizontal,'' left-right direction. As can be seen from Figure 2.7, a transverse (horizontal) plane subdivides the standing body into both upper and lower portions. Several terms of relative position are created via this plane. Superior (soo-PEER-ee-or), for instance, means ''one that is above'' (superi), while inferior (in-FEER-ee-or) denotes its opposite, ''one that is below'' (inferi). Synonyms (words with similar meaning) for superior are cranial (KRAY-nee-al), which ''pertains to the skull'' (crani) end of the body, and cephalic (seh-FAL-ik), which ''pertains to the head'' (cephal) end. A synonym for inferior is caudal (KAW-dal), which ''pertains to the tail'' (caud) end of the body.

i Superior, cranial, cephalic

Transverse (horizontal) plane i Superior, cranial, cephalic

Transverse (horizontal) plane

t Inferior, caudal

Fig. 2.7 Anatomic terms related to the transverse (horizontal) plane.

t Inferior, caudal

Fig. 2.7 Anatomic terms related to the transverse (horizontal) plane.

Using some specific examples, we can say that the nose is superior, cranial, or cephalic to the chin. In Common English, this means that the nose is above, more towards the skull end, or more towards the head end of the body, compared to the chin. Conversely, the chin is inferior or caudal to the nose. This means that the chin is located below the nose, or more towards the tail end of the body.

When an actual physical cut is made all the way through the body in a horizontal direction, the cut is called a transverse section or cross-section. This is because the cut is made all the way ''across'' the body at some particular horizontal level. Transverse (cross) sections are especially valuable in gross (macroscopic) anatomy, since they reveal many of the internal organs located within the body cavities.

0 0

Post a comment