It includes the shoulder, elbow, wrist, hand, fingers, etc., regarding its proximity to the center of the body (torso).
In most cases, the torso is the center or starting point, and the arms and legs are attachments that extend from the center.
The further an attachment or body part is from the center (shoulder, elbow, wrist, hand, fingers), the more distal it is.
Conversely, the closer the body part is to the center, the more proximal it is.
One of the easiest ways to understand the difference between proximal and distal is to think of proximal as proximity.
When one thing is within proximity to something else, it is close or nearby.
In other words, when looking at the center of the human body (i.e., the torso), the shoulder is proximal “in closer proximity” to the torso compared to the elbow, which is further away.
- Proximal = in proximity to or closer to
On the other hand, the distal can be considered distant from or further away from the body’s center.
Using the same body parts as in the previous example, if you look at the center of the human body, the elbow is distal, “further away” from the torso than the shoulder.
Distal = distant or further away from
In simple terms, proximal means that one thing is closer to the center than another, and distal implies that one thing is further away from the center.
- Proximal = nearest to, closest to, or in proximity to (closest to the center of the body or torso)
- Distal = furthest from, distant from, or further away (the farthest point from the center of the body or torso)
Regarding proximal and distal, the torso is frequently the center or origin, with the limbs considered the attachments.
However, other body parts like the hand or foot can also be the center or point of origin.
Therefore, understanding the point of origin is essential when deciding what is proximal or distal to that particular part.
Proximal vs. Distal Example #1
Using your arm as an example, we’ll compare the distance between your shoulder, elbow, wrist, and hand and determine whether or not one attachment is closer to the point of origin (torso) than another.
For example, your hand is “distal,” further away from the torso than the wrist, elbow, or shoulder.
Compared to your shoulder, your elbow is “distal,” further away from the center (torso) than the shoulder.
However, your elbow is “proximal,” closer to the center (torso) than the hand is.
Remember, proximal and distal refer to whether something is closer to or further away from the center.
Proximal vs. Distal Example #2
Using your hand as an example, consider your wrist the center of origin.
The palm, knuckles, and fingernails are attachments to the origin (wrist).
If you look at your knuckle’s distance from the wrist, they are “distal,” further away from your wrist than your palm.
However, your knuckles would also be “proximal” closer to your wrist than your fingertips, as your fingertips are the furthest point from the wrist.
Proximal vs. Distal Example #3
For the third example, we’ll use the location rather than anatomy to explain the proximal and distal differences.
If you think of your house or state as the center (origin), the further away you travel from your home, the more distal you will be.
If you live in Florida, for example, and you want to travel to New York, you can look at a map and realize that North Carolina is “proximal” closer to your home or state than New York.
As a result, you’ll reach North Carolina before reaching your final destination, New York.
You’ll also notice that North Carolina is “distal” further away from your home or state than Georgia, right next to Florida.
As you can see, your home is the center or origin.
Anything that extends from your home becomes an attachment from the center or point of origin.
Your Body as a Visual Aid
Your body is the perfect visual reference to use when trying to understand proximal vs. distal.
Extend your arm out straight in front of you, palm facing up, and look at each attachment point on your arm, starting with your shoulder (the closest point of attachment) and ending with your fingertips (the furthest point of attachment).
Now ask yourself if one point of attachment is closer to the torso (center) than another point of attachment.
For example, while extending your arm out straight in front of you, ask yourself if your wrist is closer to your torso than your elbow.
The simple answer is no; your wrist is further away from your torso than your elbow; therefore, the wrist is distal “further” to the torso when you compare it to the elbow.
With your arm extended again, ask yourself if your elbow is closer to your torso than your hand.
This time the answer is yes; your elbow is closer to the torso than the hand.
Therefore your elbow is proximal and is “closer” to the torso when compared to the hand.
Using yourself as a visual aid, you can quickly determine whether one attachment is proximal “closer to” or distal “further from” the point of origin than another.
Using Questions to Understand Proximal/Distal
If you still have trouble understanding the difference between proximal and distal, ask yourself the following questions.
It will help help you determine whether something is proximal or distal to the point of origin.
For this example, I will use the torso as the point of origin, and the limbs will be the attachments.
Is your hand closer to (proximal) or further away (distal) from the torso than your elbow?
Your hand is further away from your torso than your elbow. Therefore your hand is “distal” when compared to your elbow.
Is your elbow closer to (proximal) your torso than your hand or further away (distal)?
Your elbow is closer to your torso than your hand.
Therefore your elbow is “proximal” when compared to your hand.
Is your elbow closer to (proximal) or further away (distal) from your torso than your shoulder?
Your elbow is further away from your torso than your shoulder. Therefore your elbow is “distal” when compared to your shoulder.
Is your wrist closer to (proximal) your torso than your fingers or further away (distal)?
The wrist is closer to the torso than the fingers. Therefore it is “proximal” when compared to your fingers.
Once again, the further away something is from the point of origin or center, the more distal it is/
The closer something is to the point of origin, the more proximal it is.
When comparing one attachment to another, the closest attachment to the center/origin is proximal, and the further attachment is distal.
To learn more about this, Wikipedia has an excellent page on human anatomy, “Anatomical terms of location.