sometimes we want to be able to describe body regions and organs and describe them relative to other parts in order to do this we use directional terms sometimes it's helpful to have a point of reference that will be found in the center of the body called the midline all right it's an imaginary line that separates the body into equal left and right halves The easiest way to memorize these terms is to think of them in their pairs. For example, anterior and posterior are a pair, and their definitions are opposites. So anterior is going to be defined as toward the front. The opposite is posterior and defined as towards the back. Now, if we were to give an example, one could say that the sternum is anterior to the vertebrae.
Sometimes there's more than one grouping of words that mean the same thing. In this case, you could also use ventral and dorsal, which essentially means the same thing. Anterior is the same as dorsal and posterior is ventral.
Now, if you're having trouble remembering which is which, think of a dorsal fin on the back of a large mammal like a whale or a dolphin. Next is superior and inferior. Other terms that would mean the same are cranial, rostral, cephalic, all meaning toward the head, and inferior or caudal, meaning toward the tail.
We generally use superior and inferior when we're talking about structures that are on the arms and legs. We're going to use proximal and distal instead of superior and inferior on these appendages. So you will not use superior and inferior on the arms and legs in this course. So proximal is closest to where it attaches to the body, and distal is going to be farthest away from where it attaches to the body. So for example, if we want to describe these regions using these terms, you might say that the olecranial region, or the elbow, is proximal to the carpal region, or the wrist.
Or the tarsal region is distal to the patella region. okay um the other ones are pretty easy when we talk about the the medial and lateral we'll use the midline as a point of reference the body part that's closest to the midline is said to be medial and the body part that's farthest away from the midline is going to be said to be lateral all right central and peripheral central is saying closer to the center of the body whereas peripheral is going to be farther away from the center You can include appendages with the central region of the body using these terms, right? Ipsilateral and contralateral describe body parts that are either on the same side of the body or the opposite side of the body. This one's kind of easy to remember because when we think of contra in a word like controversy, we're describing opposite positions, all right? And it might help you remember the set of words.
Ipsilateral will mean the same side of the body. Sometimes it's helpful to think of other words you know and their definitions, especially when you're struggling to remember those definitions. Okay, so our last directional combination is going to be superficial and deep, where the superficial is going to mean closest to the surface and deep away from the surface or the surface of the body or the surface of an organ.
All right, now this might... used be used appropriately more in a situation like you know in surgery where the patient is lying supine or prone on a table okay so that's it for the directional terms