Video: Blood vessels of male pelvis

Hello, everyone! This is Joao from Kenhub, and welcome to another anatomy tutorial where, this time, we're going to be discussing the blood vessels that we find on the male pelvis. And, to do so, we’re going to be exploring this image, mainly this image that you see now on the screen, which is essentially a lateral view of the male pelvis. So, if we cut here the male pelvis then expose some of the main structures here, some of the organs like the urinary bladder, you can also see here the part of the rectum, and all these structures that we’re going to be talking about the blood vessels here which you see here in red, the arteries, and then in blue, the different veins that will supply the different structures of the male pelvis.

Now, the arteries and veins of the male pelvis are similar to those that you find on the female pelvis with the exception of the blood vessels of the genitalia which differ, of course. Now, let’s begin by looking at the blood vessels that supply oxygenated blood to the pelvis – so, the arteries.

And we’re going to highlight here the very first one that you see now on this image, notice here, the main one that will be supplying blood here – oxygenated blood – this is then the abdominal aorta. Now, the abdominal aorta is without a doubt the largest blood vessel found in the abdominal cavity giving off many branches that supply much of the abdominal cavity as well as lower extremities. Now, if you remember, this structure enters the abdomen through the diaphragm at the level of T12 and descends down through the abdomen anterior to the vertebral bodies of L1 to L4 giving off numerous branches until it then bifurcates at the level of L4 – so this is where it’s going to be bifurcating. And you can also see here on this image – we removed here L4 – but this is where you see a bit of location here L5, L4 should be here, this is where the bifurcation of the abdominal aorta is going to be happening. And when it bifurcates, it will then split into the left common iliac artery and the right common iliac artery at approximately this level. And on this image you can see here then the left common iliac artery, and a cut of the right one here.

I would like to also show you this image here of the anterior view of the open abdomen where you can then see the highlighted here, abdominal aorta, and notice how it bifurcates into the two common iliac arteries.

Moving on to the next structure that we’re going to be seeing here on the male pelvis highlighted in green, we see now the median sacral artery. Now, the median sacral artery is a small vessel that will be arising from the posterior side of the abdominal aorta just superior to its bifurcation. It will then descend in the midline along the anterior surface of the sacrum which you can also see here – so this is the sacrum and we just made a cut here of the sacrum. But notice how it is then on the, or descending on the anterior surface of this bone. Let me add that does so also to the coccyx. Now, this artery anastomoses or forms a connection with the iliolumbar artery and the lateral sacral arteries while also providing small branches to the posterior surface of the rectum.

The next structures we’re going to be highlighting – a very important one that you see here – this is then the external iliac artery. Specifically, we’re looking now at the left one, but there sure is a right one. And, as I mentioned before, the abdominal aorta will be bifurcating giving the two common iliac arteries and each of these arteries or two arteries is giving off two terminal branches, the internal iliac artery and the external iliac artery, which you see now here. The internal one which we will talk about is this one here, as you can see.

The external iliac arteries are paired arteries that are the second branches from the common iliac arteries then and the left and right external iliac arteries travel inferiorly, laterally and anteriorly in the pelvis giving off two branches, the inferior epigastric artery and the deep circumflex iliac artery and finally continuing as a very important artery of the lower extremity, the femoral artery, which is the terminal branch then.

The next artery that we’re going to be highlighting I mentioned before briefly, this one is then the internal iliac artery. Now, this is the other terminal branch of the common iliac artery. It is also a paired artery so you have one on the left side and one on the right side, and the first branch from the left and right common iliac arteries. This paired artery is considered to be the main artery of the pelvis as it provides branches that will be then supplying a lot of structures including the walls and viscera of the pelvis or the organs of the pelvis, and the reproductive organs, the buttocks and the medial compartment of the thigh.

Just would like to give a quick word on the branches of the internal iliac artery. The internal iliac artery also bifurcates to give an anterior and posterior main branch and many of the branches of the internal iliac artery are the same as those found in the female pelvis with the exception of the branches that supply the reproductive organs. It is important to note that all the branches of the internal iliac are paired arteries. So, if you find them on the left side, you sure will find them on the right side.

Throughout the rest of the tutorial, I will refer to each artery in singular form but please keep in mind that even though I am referring to the vessels in the singular form, I am actually referring to the two identical arteries found on either side of the pelvis. The branches of the internal iliac artery in the male pelvis include a posterior division which include the following branches: the iliolumbar artery, the superior gluteal artery, the lateral sacral arteries. And then there is an anterior division which has a bit more branches which include the obturator artery, the umbilical, the superior vesical, the inferior vesical, the internal pudendal artery which then divides into the dorsal artery of the penis and the inferior rectal artery, and the middle rectal artery, and finally the inferior gluteal artery.

Let’s start with this one that you see here highlighted in green – notice here on the image – this highlight here is showing the iliolumbar artery. So, this one is the first branch of the posterior division of the internal iliac artery. Now, the iliolumbar artery is first branch to arise from the posterior division of the internal iliac artery. It arches backward and ascends laterally out of the pelvic inlet towards the iliac fossa. It will further divide into two branches: the lumbar branch and then iliac branch, hence, the name iliolumbar artery. Now, in this illustration, you can see the left iliolumbar artery highlighted.

Next, we’re going to be highlighting this one that you see now on the screen, this is the lateral sacral artery. Now, the lateral sacral arteries are the next arteries that originate from the posterior division of the internal iliac arteries. They course inferiorly along the posterior pelvic wall and give branches that will supply the bony elements of the sacrum and the coccyx as well as the skin and muscles posteriorly, found posteriorly, to the sacrum.

The next artery that we’re going to be highlighting here, this one is known as the superior gluteal artery. Now, this is the last artery that arises from the posterior division of the internal iliac artery. It is also the largest branch of the internal iliac passing through the suprapiriform foramen of the greater sciatic foramen to enter the gluteal region then. This one provides branches that supply the gluteus maximus, medius and minimus and the tensor fascia latae. So, a lot of muscles are supplied by the superior gluteal artery.

The next one we’re going to be highlighting here, you can see now the umbilical artery, which belongs to the anterior division of the internal iliac artery. This is the first inferior branch of the anterior division of the internal iliac artery. The patent part of the umbilical artery is the part of the embryonic umbilical artery that does not get obliterated postnatally. It is this part of the artery that gives rise to the superior vesical artery which we will talk about later and the artery of the ductus deferens in the male pelvis. In adults, the umbilical artery is obliterated beyond the bifurcation of the superior vesical artery.

On the next image, we’re going to be highlighting this one that you see, this artery which is known as the superior vesical artery which represents the terminal section of the umbilical artery on the left and right side. In this illustration, you can see the superior vesical artery here highlighted in green. Now, the superior vesical arteries course along the upper and middle segments of the urinary bladder and then supplies the superior aspects of the bladder and the distal parts of the ureter.

The next artery that we’re going to be highlighting here, now this one is known as the obturator artery. This one will be supplying the adductor muscles. The obturator artery passes anteriorly and then travels downward coursing along the lateral wall of the pelvis and passing through the obturator foramen on both left and right sides of the pelvis. Now, this artery gives off branches as it courses inside the pelvis as well as the posterior and anterior branches once it passes through the obturator foramen. In this illustration, you can then see the left obturator artery of the male pelvis highlighted in green.

Next artery that we’re going to be highlighting here is known as, collectively, as the inferior vesical arteries. On this image, you can see the right one and, on this image, notice here the left one. The inferior vesical arteries arise from the anterior division of the internal iliac artery. They’re only found in men and supply the inferior or fundus or lower part of the bladder and the seminal vesicals. This artery also gives off prostatic branches that supply then the prostate and you can see here on this image, the prostate.

Next, we’re going to look at this artery here – a very important one – which is known as the internal pudendal artery. The internal pudendal arteries together with the inferior gluteal arteries represent the terminal branches of the anterior division of the internal iliac artery. The left and right internal pudendal artery supply oxygenated blood to the external genitalia. This artery is larger in the male pelvis than in the female pelvis. It passes through the greater sciatic foramen and also through the lesser sciatic foramen to then the lateral wall of the ischiorectal fossa giving off several branches to the perineum, the urethra, the posterior part of the scrotum, and the penis. And, in addition, it will give off then the deep artery of the penis, the perforating arteries of the penis, and the dorsal artery of the penis in the male pelvis. Finally, it gives rise to the inferior rectal artery and, for more information on the branches of the internal pudendal artery in the female pelvis, you should check out the tutorial on the blood vessels of the female pelvis here on Kenhub.

The next arteries that we’re going to be highlighting here, this one is known as the posterior scrotal branches of the internal pudendal artery. Now, we just covered the internal pudendal artery on the previous slide. Now, let’s take a look at its branches found then in the male pelvis. Now, the posterior scrotal branches of the internal pudendal artery arise from the internal pudendal artery and then pass to the scrotum which you can clearly see here on this image.

Next one that we’re going to be seeing here is known as the dorsal artery of the penis which you see here highlighted in green. Now, this one is another branch of the internal pudendal artery and it ascends between the crus of the penis and the pubic symphysis on the dorsal aspect of the penis to the glans penis. It forms an anastomosis or a connection with the deep artery of the penis and then supplies oxygenated blood to the foreskin, the glans penis, and the fibrous sheath of the corpus cavernosum.

The next artery that we’re going to be highlighting here is known as the inferior rectal artery – notice it here highlighted in green. And, as I just mentioned earlier, the inferior rectal artery is one of the branches of the internal pudendal artery. This artery courses transversally through the ischiorectal fossa providing blood supply to the lower half of the anal canal including both sphincters and the skin below the anal valves. Here, in this illustration, you can see the right rectal artery as seen on the male pelvis.

The next arteries that we’re going to be highlighting here are known as the middle rectal arteries. Now, going back to the branches of the anterior division of the internal iliac artery, the last arteries we are going to look at are these, the middle rectal arteries. And notice here on this image, here is the right one and on this image, we just highlighted the left one. This artery crosses the pelvic floor on its way to the rectum and then supplies oxygenated blood to the rectal muscles. But, it also gives off branches to the lower part of the prostate and the seminal vesicals. These arteries form anastomosis with the inferior vesical artery, the superior rectal artery, and the inferior rectal artery.

The next artery that we’re going to be highlighting here on this image – notice here superiorly – this one is known as the inferior mesenteric artery. And we just see a little bit of this artery here but it’s a very important one. Now, this is another important artery that supplies the male pelvis and it is the third branch of the abdominal aorta that arises from the anterior aspect at approximately the level of L3 to L4. Now, this one is an unpaired artery that passes to the left, supplying then the descending colon, the sigmoid colon and the rectum. This artery is also important because it gives off the superior rectal artery. And I would like to show you here this image of the anterior view of the abdomen where you can then see the inferior mesenteric artery branching off of the abdominal aorta.

And, as we mentioned before, let’s move on and talk about this branch – one of the branches – of the inferior mesenteric artery, this is the superior rectal artery. So, this one is an exception. This is not a branch of the internal iliac artery so keep that in mind. This is a branch of the inferior mesenteric artery. So, this artery is going to be supplying the rectum including the mucosa up to the anal valves and is a branch of then – just a reminder here – of the inferior mesenteric artery. The superior rectal artery runs behind the rectum descending into the lesser pelvis and dividing into a left and right branch before piercing the musculature of the bowels. And you can even see here how it divides into two branches.

Up until now, we have looked at the arteries that supply the male pelvis. Next, we’re going to look at the veins that provide venous drainage in this area. It is important to note that the veins of the male pelvis, generally speaking, follow the course of the branches of the internal iliac artery. And, as you will see in the following slides with the exception of the superior rectal veins, now these veins drain into the internal iliac vein and finally to the common iliac vein. And you see here then the internal iliac vein and the common iliac vein.

So, let’s look at the first vein that you see here highlighted in green – notice this vein here – this is known as the deep dorsal vein of the penis. Now, the deep dorsal vein of the penis is located between the deep fascia of the penis and the tunica albuginea. It carries deoxygenated blood from the glans penis and corpus cavernosum and communicates with the internal pudendal vein. Finally, it will join with the prostatic venous plexus.

The next vein that we’re going to be highlighting here is known as the posterior scrotal vein, and these are small veins arising from the posterior part of the scrotum – as you can see here – and these veins carry blood from the posterior part of the scrotum and open into the vesical venous plexus.

Next, we’re going to be seeing here highlighted in green, this vein which is known as the lateral sacral vein or the lateral sacral veins because you have one on each side. Now, the lateral sacral veins are tributaries of the internal iliac vein which you also see here on this image and they course from the sacral venous plexus alongside the lateral sacral arteries on the anterior surface of the sacrum to then the internal iliac veins.

Next, we’re going to be highlighting here the superior rectal vein, and the superior rectal veins course alongside with the superior rectal arteries leaving the lower pelvis and crossing the common iliac vessels to continue upwards as the inferior mesenteric vein. Now, these veins will be draining blood from the veins surrounding the rectum into the inferior mesenteric vein. And, unlike the middle and inferior rectal veins, the superior rectal vein does not drain into the internal iliac veins – keep that in mind.

The next vein we’re going to be highlighting here or next veins – as you can see on the left side here – on this image on the left side, you see the left one and the image here on the right side, we’re highlighting the right one, these are then the middle rectal veins, similar to what we’ve seen when we talked about the arteries. Now, the paired middle rectal veins, they arise from the hemorrhoidal plexus also known as the rectal venous plexus. Some tributaries of the middle rectal veins also come from the urinary bladder, the prostate gland, and also the seminal vesicals. They also form connections also known as anastomosis with the superior rectal vein and the inferior rectal veins. Now, the middle rectal veins open into the internal iliac veins.

Next, we’re going to be highlighting now the inferior rectal veins which you can see here. Now, the inferior rectal veins drain deoxygenated blood from the inferior part of the external rectal venous plexus into the internal pudendal vein. These veins may become varicose resulting in external hemorrhoids also known as piles. They also anastomose with the superior rectal vein and the middle rectal veins. Now, the internal pudendal veins in turn open into the internal iliac veins.

Next, we’re going to be highlighting here the superior vesical veins and they drain the upper and middle portion of the urinary bladder into the internal iliac veins.

Next, we’re going to see here now the inferior vesical veins. On this image, you see the left one while on this image then you see the right one. The inferior vesical veins open or drain into the internal iliac veins and, when we talk about the vesical veins, we are basically talking about the veins arising from the vesical venous plexus. Now, this plexus arises from the base of the bladder and communicates with the prostatic venous plexus in the male pelvis.

Now, we’re going to see here highlighted in green, this vein which is known as the superior gluteal vein. This is specifically the left superior gluteal vein but there are two – one also on the right side. Now, these veins leave the pelvis through the suprapiriform foramen of the greater sciatic foramen into the pelvis accompanying the superior gluteal arteries that we saw before on previous slides. Now, they receive tributaries from the buttocks and unite to form a trunk that opens into the internal iliac vein.

Next, we’re going to be highlighting here – this one that we also saw or learn about the artery – this one is the obturator vein, specifically the left obturator vein because there is also a right one. Now, this one, or the obturator veins, they open into the internal iliac veins. They pass into the male pelvis through the obturator foramen and have an anterior and posterior branch in the same way as the obturator artery. Now, they drain blood from the hip joint and surrounding muscles.

Finally, on this tutorial, we’re going to be highlighting here – this vein – this is then an important one known as the external iliac vein. The external iliac veins are paired veins. We’re looking now at the left one but there is the right one. They arise from the upper part of the femoral veins. These veins course along the external iliac arteries. They join with the internal iliac veins to then form the common iliac veins on both the left and ride side. You can see here that this one joins here with the internal iliac to then form the left common iliac vein.

Now that you just completed this video tutorial, then it’s time for you to continue your learning experience by testing and also applying your knowledge. There are three ways you can do so here at Kenhub. The first one is by clicking on our “start training” button, the second one is by browsing through our related articles library, and the third one is by checking out our atlas.

Now, good luck everyone, and I will see you next time.