Proximal vs Distal - page 2
Can somebody please explain to me what these terms mean in plain English? I cannot seem to grasp this.... Read More
May 22, '13For things that are not limb-oriented, the head is typically used as the point of reference.
For example, when talking about the esophagus, the "mouth end" is the proximal portion and the "stomach end" is the distal portion.
May 9, '15I did not know how to post a new thread, so I was hoping that you could answer some questions for me. I cannot seem to grasp the difference between proximal and distal. I know that distal is farthest away, and proximal is closet. I need some examples. What exactly is the main point of attachment they talk about? For the arm, would it be the shoulder, and for the leg would it be the hip. What is the elbow to the wrist or the shoulder? What is the fingers to the wrist or the elbow? Any help you can give me would be greatly appreciated. Thanks!
May 10, '15Quote from ryan62568I'm not really sure how else to describe this to you... you have the main points.I did not know how to post a new thread, so I was hoping that you could answer some questions for me. I cannot seem to grasp the difference between proximal and distal. I know that distal is farthest away, and proximal is closet. I need some examples. What exactly is the main point of attachment they talk about? For the arm, would it be the shoulder, and for the leg would it be the hip. What is the elbow to the wrist or the shoulder? What is the fingers to the wrist or the elbow? Any help you can give me would be greatly appreciated. Thanks!
Proximal is closest, distal is farther away. Point of attachment is where the limb attaches to the torso. Stick your left arm straight out to your side.
Is your elbow closer or farther away than your shoulder? It's farther away, so it is distal to the shoulder.
Is your wrist closer or farther away from your shoulder than your elbow? The wrist is farther away, so it is distal.
Is your palm closer or farther away than your fingertips? It is closer, so it is proximal.
The distal portion of your finger is the end that is the most distance away from your body/torso (in other words, the end with the fingernail). The proximal portion of your finger is closer to the palm.
The idea of proximal/distal is that by using the same wording/definition system, you can always know what portion of the body is being discussed regardless of the position of the body and the individual limbs.
For example, if the arm is held straight out to the side, the wrist end of the radius and ulna are farther away from your torso and the elbow is closer. But if you bend your elbow so your fingers can touch your shoulder, now the wrist end is closer to the torso than the elbow is. If there was a fracture of the radius "on the end closer to the torso" then the location of the fracture would be different based on whether the elbow is bent or if the arm is straight.
But by using proximal and distal using the point of attachment as the reference point, the placement/positioning of the arm has no bearing on which end is closer and which is farther away.
Another way to think of it is to mentally take a string and a thumbtack and affix one end of the string to the middle of the chest (ouch!). If you run the string along the body to the shoulder / elbow / wrist / finger and compare the measurements of each, no matter what position (up, down, left, right, bent, straight) the arm is placed in, the length of the string to the elbow is always going to be shorter than the length of the string to the wrist.
Take the same string (still attached to the chest...ouch!) and now run it down the leg instead.... the string length to the knee will always be shorter (proximal) compared to the string length to the ankle.
Another way to think of it -- you're going on vacation and you can either fly or drive. To get from the southern part of Texas to the southern part of Florida, the distance involved is much more if you drive up Texas, across the Gulf states, and then down Florida versus if you flew directly from the tip of Texas to the tip of Florida over the Gulf. But the actual distance between the two points never changed... just the way you looked at them.
Using distal/proximal is looking at the human body as if it were a continent you need to drive on, with hopping on a plane not being an option. If you have to drive from the heart to the wrist, it's going to be a farther distance than if you have to drive from the heart to the elbow.