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These arteries named anatomically, so they follow the route of the arm. Right Subclavian comes off the Brachiocephalic Trunk, Left comes from the aortic arch. In my CCA in year 2 I got a question saying which artery supplies the arm and the face, and I was told to point at it on the model of the heart. The answer was the brachiocephalic trunk, but my point is that don’t forget the bigger picture in this sort of stuff. At the lateral border of the first rib, the subclavian artery enters the axilla – and is renamed the axillary artery. The brachial artery is then a continuation of the axillary artery past the lower border of the teres major. It is the main supply of blood for the arm. For BP next term you’ll learn to feel the brachial pulse. Then the brachial artery bifurcates as it enters the cubital fossa, where it splits into the radial and ulnar arteries which supplies the respective parts of the arm. The radial and ulnar arteries will then continue to enter the hand, the ulnar entering it anteriorlyThe radial and ulnar arteries will then continue to enter the hand. The ulnar artery entering enters anteriorly and it forms the superficial palmar arch. The radial artery enters dorsally and it forms the deep palmar arch. Both of these arch give of branches which allow them to connect.Basilic vein runs medially in the aat the border of the teres major, the vein moves deep into the arm. Here, it combines with the brachial veins from the deep venous system to form the axillary vein. Cephalic vein is more lateral. At the border of the teres major, the vein moves deep into the arm. Here, it combines with the brachial veins from the deep venous system to form the axillary vein. The cephalic and basilic veins are connected at the elbow by the median cubital vein.This will definitely come up in your CCA at the end of the year, where you’ll be ask to point out the nerve. They could say for example, point out a nerve that come the medial cord of the bracnial plexus , and you'd be expected to point out either the median nerve or ulnar. SO CONCENTRATE! The Plexus comes from divisions of the Cervical Spinal nerves :C5, C6, C7 and C8, and the first thoracic spinal nerve, T1. The brachial plexus is divided into five parts; roots, trunks, divisions, cords and branches. It’s easy to learn the image, but it’s better if you get visual understanding. I will try explain both, but will begin with this 2D version first. Let’s start of with our roots, you have C5 and C6 which come together to give the superior trunk. C7 root is on its own and gives rise to the middle trunk, then C8 and T1 come together to give the inferior trunk. Each one of these trunks has an anterior and posterior division (there basically branching off). Switch to next slide to see thedivisions better.As you can see, Each one of the trunks has an anterior and posterior division (there basically branching off). Each division gives rise to a cord. The lateral cord is formed from the anterior divisions of the Superior and Middle Trunk. The posterior Cord is formed by all of the posterior divisions of the three trunks, so superior, middle and inferior. Easy to remember, posterior cord, comes from all posterior division. The only division that’s left now is the anterior division of the inferior trunk which gives rise to medial cord. I hope that makes sense. Easy way to remember I would say is Posterior Cord = posterior divisions of all 3 trunks. Lateral Cord = anterior division of superior and middle trunk. Medial Cord = Anterior Division of inferior trunk. Now, each of these cords gives off nerves. You don’t need to knowwhich branch of the cords gives it like its showing in the picture. All you need to know is which cord gives off which nerve. For your basic understanding, like enough to pass the exam, just memorise them : LMM (lateral gives off musculocutaneous + median) PAR (Posterior cord gives off axillary and radial). And MMU - Medial cord gives off median and ulnar. But i think true understanding, and what you need to know for your CCA is that from this entire brachial plexus, the only part we can see in the arm is from the Lateral, Posterior and Medial Cord. and these 3 cords surround the axillary artery in the arm. Switch to the next slide.You can see the axillary artery here in red, and i’ve just shown you that it continues to become the brachial artery at the bordelower border of the teres major. On the medial side of the axillary artery, you’ll find the medial cord. Posterior to the brachial artery, you’ll find the posterior cord and then on the lateral side you’ll find the lateral cord. It makes a lot more sense, now that you know that it’s all named anatomically based on how they surround the axillary artery. The thickened parts are the cords on this drawing. Let’s look at the posterior cord first, its the dashed line just to show it’s posterior. It gives rise to two nerves, the one going up into the axilla is the axillary nerve. The nerve that comes down from it, and is on the side of the radius is the radial nerve. The radial nerve is going to innervate the posterior arm, so anatomically it makes sense for it come from the posterior cord and for it to be posterior. Then let’s look at the lateral nerve, it gives off the musculocutaenous nerve, which you can literally see piercing into the muscle it innervates, so its easy to figure that one. It also gives off one morebranch which we will discuss in a min. Now your medial cord, gives off first your ulnar nerve. This makes sense because remember your ulna is medial, so the most medial nerve has to be ulna. Then the medial cord gives a branch which, joins the branch from the lateral cord to form the median nerve. Using this diagram, you’ll easily be able to see the nerves in your CCA and in dissection. If your confused, start of by finding the axillary artery and then figure out the cord after that. Hopefully that makes sense. In your CCA, when you get asked to point out a nerve in the arm, unless you can obviously see it, I want you to do these following steps : 1. Find the axillary artery, its the big bouncy artery, close to the top of the arm , in the arm pit area.