 This is a supine cadaver. I'm standing on the right side camera person is also the right side This is the brachycephalic trunk, which I've lifted up here at the thoracic inlet and from the brachycephalic trunk We can see this branch coming out. This is the common carotid artery on the right side. This is the subclavian artery This is a digital subtraction angiogram showing right subclavian artery and the right common carotid artery The subclavian artery has got three parts The first part is the portion proximal to the scalinus anterior muscle So therefore the first part is from here to here Then there's a second part which is behind the scalinus anterior muscle and that portion We have cut and we have taken it out because that's the only way we can see it And then we have the third part which comes from the scalinus anterior muscle to the outer border of the first trip Which is here after that it becomes known as axillary artery So these are the three parts of the subclavian artery So let's take a look at the branches coming out from the first part of the subclavian artery We see this artery which I have lifted up here This is the vertebral artery in the neck. It travels in a triangular space Which is bounded laterally by the scalinus anterior muscle and Medially by a muscle here called the longest coli muscle So it goes through that triangular space and then it disappears in the deep part of the neck after that It travels through the transverse foramen of C6-5-4-3-2-1 And then it pierces through the posterior gland occipital membrane and becomes Intracranial where it supplies a posterior cerebral circulation. So this is the vertebral artery This is a three dimensional demo flight spoiled gradient recall MR angiogram showing the vertebral artery The next branch is this one here We had to cut it because the rest of the artery is inside the thorax and we can see the cut portion of the artery here This is the internal thoracic or the internal mammary artery This runs on the inner surface of the chest adjacent to the Sterlo the third branch from the first part is this one which I have lifted up here This is the thyro cervical trunk The thyroid cervical trunk itself has got four branches and we can see three of those branches. The first is this one here This is the inferior thyroid artery and I will draw your attention to the course of the inferior thyroid artery and the relationship We can see the inferior thyroid artery first goes up and Then it goes down and it enters into the lower pole of the thyroid gland This is the inferior thyroid artery and here it is in close proximity to this nerve here This is the right recurrent laryngeal nerve. It is formed as a branch from the Vegas. This is the Vegas We can see it is crossing in front of the subclavian artery on the right side and it is giving this branch here and This branch is then hooking under the subclavian artery and we can see that branch here And this is the right recurrent laryngeal nerve This is a very important relationship when we are doing a thyroctomy and we have to like it The inferior thyroid artery we are liable to injure the recurrent laryngeal nerve producing horses So therefore the rule of thumb is well like getting the inferior thyroid artery We should like it very far from the gland like what I'm shown here with my instrument So as to spare the recurrent laryngeal nerve. This is the inferior thyroid artery This is one of the terminal branches of the thyroid cervical trunk. The other terminal branch is visible here This is the other terminal branch This is the ascending cervical artery which runs up in the neck The third branch of the thyroid cervical trunk is this artery This is the suprascapular artery and we can see it is running transversely laterally And it is accompanied by the suprascapular nerve and it is accompanied by the suprascapular vein The fourth branch is supposed to be transversed cervical But we here we cannot see the transversed cervical Now this transversed cervical the fourth branch of the thyroid cervical trunk is a little controversial Some books call it cervical dorsal artery and this is supposed to divide into a superficial branch and a deep branch And the deep branch is also referred to as dorsal scapular and I shall show you the dorsal scapular just now from a different branch So that is about the branches from the first part of the subclavian artery Now let's come to the second part of the subclavian artery Which I told you is behind the skeletonus anterior muscle and as I said we have cut it and we have taken it out So this portion was behind the skeletonus anterior muscle. This is the branch from the second part And this is the costoservical trunk The other part of the costoservical trunk is here This costoservical trunk according to the textbooks ideally is supposed to give two sets of branches One is a deep cervical which supplies the deep muscles of the neck and the other is the supreme or the superior intercostal Which supplies the first posterior intercostal space. Here we will see something a little different This is the costoservical trunk and when I'm pulling here you can see this is moving So this is the other end of the costoservical trunk and if you go to look here We see that this costoservical trunk is giving the following branches This is the first one This is the supreme or the superior intercostal which supplies the posterior intercostal space the first or the first or second This is deep cervical which supplies the deep muscles of the neck and this is giving the dorsal scapular artery Which I said comes from the transverse cervical But here it is coming from the costoservical trunk and this is going on the dorsal aspect of the chest Participates in the scapular and astromosis Then we have the third part of the subclavian artery, which is the portion Lateral to the skeletonus anterior from the skeletonus anterior to the outer border of the first trip ideally the third Part of the subclavian artery does not have any branches But sometimes it can give rise to the dorsal scapular artery or the upper artery The important thing about this third part is that it runs through this triangular space bounded by the skeletonus anterior medially and the skeletonus medius laterally and Mounted by the first trip below this triangular space is referred to as a scalyne triangle and the third part is running through the triangular space along with the upper trunk middle trunk and the lower trunk of the brachial plexus and either or any of these can be compressed In an abnormal insertion of the scalyne anterior muscles or by a cervical rib or by many other factors And that is referred to as the scalyne syndrome or the costoclavicular syndrome or the thoracic inlet syndrome So this is about the subclavian artery Thank you very much for watching. Dr. Sanjay Sanyal signing out. Please like and subscribe if you have any questions or comments Please put them in the comment section below. Have a nice day