This is a tutorial on the arteries of the body. I’ll cover some of the important arteries that you need to know.
Starting from the heart, I’ll start with this artery here, the pulmonary trunk, which comes from the right side of the heart and pumps deoxygenated blood to the lungs.
The pulmonary trunk bifurcates into left and right branches. You’ve got the left and right pulmonary artery. You can see that there. The right pulmonary artery just passing underneath the arch of the aorta.
On the left side of the heart, the left ventricle pumps blood out through the arch, through the aorta, which arches over the pulmonary trunk. At this level of the arch of the aorta where the pulmonary trunk bifurcates is the level of the Angle of Louis, so the junction of vertebra T4/T5. The Angle of Louis is where the manubrium of the sternum meets the body of the sternum.
If I just show you that quickly, this junction here is the Angle of Louis, the sternal angle. That’s the disc between T4 and T5.
The arch of the aorta has three branches coming off of it, which you can see here. The first branch is the brachiocephalic trunk. This second branch in the middle is the left common carotid and this branch here is the left subclavian artery.
There’s a mnemonic for remembering the branches of the arch of the aorta, ABCs (as in learning your ABCs) – a for aorta, b for brachiocephalic trunk, c for common carotid (so the left common carotid) and S for subclavian (left subclavian).
This branch here, the brachiocephalic trunk then splits into two branches. You’ve got the right subclavian here and the right common carotid. Just like you’ve got the left common carotid here, you’ve got the right common carotid here, which branches off from the brachiocephalic trunk.
Just following the common carotid arteries up a bit further, they then split into another three branches. You’ve got the internal carotid and the external carotid coming off the common carotid artery. The external carotid artery has loads of branches. These supply the head and face. You can see all these arteries on the face. These are branches of the external carotid artery.
The internal carotid artery however runs straight up to join the base of the brain at the Circle of Willis, this arterial circle at the base of the brain which supplies the brain. The internal carotid goes up to meet that.
Next along, an important artery to note is this one coming off the subclavian. You’ve got this on both sides. It’s called the vertebral artery. You’ve got the common carotid coming off the brachiocephalic trunk on the right side and you’ve got the subclavians on either side and you’ve got the vertebral artery, which comes off the subclavian.
You can see the course of this artery. It runs up through the transverse foramen of the cervical vertebra. You can see this transverse process here and you can see this artery running up alongside the vertebral vein through the transverse foramen. The vertebral artery runs up and it meets the basilar artery to join the Circle of Willis and supplies the posterior parts of the brain. That’s the vertebral artery which comes off the subclavian.
I’m just going to follow this course with the subclavian artery and we’ll show you what that extends down to.
The subclavian artery, you can see it running here underneath the clavicle. That’s why it’s called the ‘subclavian’ – sub- meaning under and –clavian refer to the clavicle. It runs underneath the clavicle.
The subclavian artery becomes the axillary artery. And it becomes the axillary artery at the level of the lateral margin of the first rib. The axillary artery runs here. The ‘axillary’ refers to the armpit. It runs in the armpit region.
If we just follow it down, you can see the artery running down the humerus. This artery is the brachial artery. The brachial artery then splits into two. You’ve got the radial artery and the ulnar artery.
Remember, radial is lateral in the anatomical position. The radius is lateral and the ulnar bone is media. Often in clinical medicine, you’ll hear the words ‘radial’ and ‘ulnar’ referral to lateral and medial because in the anatomical position, the radius is lateral and the ulnar is medial. The radial artery runs along the radius and is lateral and is on the thumb side. The ulnar artery runs along the ulnar side and is medial and is on the side of the little finger.
Following the artery a little bit further down, you can see the blood supply of the hand. You can see these arches here. This is the superficial palmar arch and you’ve got the deep palmar arch. The superficial arch is obviously close to the surface of the palm because it’s superficial and the deep palmar arch is deeper obviously.
The superficial arch, as you can see, is further towards the fingertips. It’s more distal. The deep palmar arch is more proximal.
I’m just going to return back to the center of the body, back to the aorta. We’re going to follow it now down towards the abdomen and lower limbs.
The aorta can be divided into five sections. The bit between the heart and this arch is called the ascending aorta. You’ve got this ascending portion. And then you’ve got this arch-shape. This is the arch of the aorta. And then you’ve got the descending aorta, the section from the arch of the aorta to the point where it divides into the common iliac arteries down here. That’s the descending aorta.
And then you can divide it into the thoracic and abdominal aorta. The thoracic aorta is the section of the aorta which is above the diaphragm.
The abdominal aorta is the section below the diaphragm. So I just added in the diaphragm, which separates the thoracic and abdominal parts of the aorta. You can see it looping over – the ascending, the arch, the descending portion. You’ve got the thoracic aorta, which is above the diaphragm and the abdominal aorta which is below the diaphragm.
Just looking at the abdominal section of the aorta, you can see these three branches here which are coming off it. I’ve removed a lot of the arteries here because it makes it a little bit more complicated. I’ve left some of the main branches of the aorta, but I’ll be covering the other branches in tutorials on the abdominal organs.
This top branch here is the celiac axis. It has three branches. It’s called the common hepatic artery, the left gastric artery and the splenic artery. The branch below is called the superior mesenteric artery and the branches below that, which comes off the aorta is the inferior mesenteric artery.
The celiac axis supplies four gut structures, the superior mesentery artery supplies mid-gut structures and the inferior mesenteric artery supplies hind gut structures.
Here you’ve got another bifurcation. This is the bifurcation of the descending aorta. This occurs at approximately the level of the L4 vertebra (the fourth lumbar vertebra). This splits into the communication iliac arteries. You’ve got the right and left common iliac artery. This then splits. Just like carotid arties, it splits into the external and the internal iliac arteries.
Just quickly to give you some perspective on whereabouts we are in relation to other structures, I’ll just put in the bladder. You can see where the bladder sits in relation to the bifurcation. You can see the kidneys. I’ll just show you in relation to surface anatomy so you can see the umbilicus. This sits it around the level of L3-L5 vertebra. Approximately, very close to where the aorta bifurcates.
Just going back to the external iliac arteries, which come off the common iliac, they then become the femoral arteries at roughly the level of the head of the femur. You’ve got the femoral arteries, which run down the length of the femur on both sides.
We’re now at the level of the knee. I’m just going to rotate this model so we can look at the back of the knee. You’ve got the femoral artery here running down and it becomes the popliteal artery. This area at the back of the knee, this bit at the back of the knee is called the popliteal fossa. This artery is called the popliteal artery.
The popliteal artery then splits into a couple of branches. You’ve got the anterior tibial artery, which branches off from the popliteal artery and runs down the course of the tibia on the anterior aspect. Here, we’re looking at the front of the body, the anterior surface of the tibia.
At the back, so you can see here the popliteal – let’s just zoom in a bit more. The popliteal artery branches off and you can see it winding around here just underneath the tibia to form the anterior tibial.
And then at the back, you’ve got two branches. You’ve got the posterior tibial. The popliteal artery splits into the posterior tibial here. The posterior tibial artery runs down the posterior surface of the tibia and you’ve got the peroneal artery, which runs down laterally on the posterior surface.
Just to recap, you’ve got the popliteal artery, which branches off into the anterior tibial, which winds around to the anterior surface of the tibia. You’ve got the posterior tibial, which descends along the posterior surface of the tibia and the peroneal artery.
Just moving down to the foot, you can see this arterial arch on the foot, which forms from the anterior tibial artery. In the feet, you’ve got this artery here, which is the arcuate artery. You’ve got this artery here, which is the dorsalis pedis artery. This is important because in a vascular evaluation, you palpate this pulse.
This pulse, if I just put in the muscular system, you’ll be able to see this tendon here, which runs up and extends the big toe. This is the extensor hallucis longus tendon. The dorsalis pedis artery is just lateral to the tendon of the extensor hallucis longus.
Those are the arteries of the body, some of the important ones that you need to know. I’m just quickly going to show you some of the pulses that are palpable.
In a vascular examination, you palpate a few pulses. You palpate one at the neck, the carotid pulse. You can see that this is palpable between these muscles here, the carotid artery. At the arm, there are two pulses you palpate, one just at the elbow. You’ve got the brachial artery, which you palpate here, medial to the biceps tendon. And at the wrist, you palpate the radial artery here.
You can see the femoral artery passing through here quite superficially, so this pulse is also palpable. This, you can feel between the midpoint of pubic symphysis and the anterior superior iliac spine. This is the femoral pulse you feel here between the pubic symphysis and the anterior superior iliac spine.
Behind the knee, you can palpate the popliteal pulse. So this, you can feel between the head of the gastrocnemius muscle. And in the feet, you can palpate the posterior tibial pulse, which runs just behind the medial malleolus of the tibia. As I’ve mentioned before, you can palpate the dorsalis pedis artery, which runs lateral to the tendon of the extensor hallucis longus.
Those are the arteries, some of the important arteries that you need to remember in the body.