 Good day everybody. Welcome to the next section. This is Dr. Sanjay Sanyal, professor and department chair of analytical sciences. Today we are going to demonstrate the muscles of the forearm and the muscles and the structures in the hand. So this is the flexor aspect of the forearm that you see here and this is the extensor aspect of the forearm. Let's take a quick look at what we can see in the flexor aspect of the forearm. Take a look here. This is the flexor carbide radialis tendon and right next to that we can see the palmaris longus tendon. The palmaris longus tendon does not have any much functional use so therefore it is used mostly for tendon transplant purposes and you can see that palmaris longus tendon is getting attached to the transverse carpal ligament or the flexor retinoculum here and it's also getting attached to the palmariponurus. But I'm going to tell more about that later on. Let's continue. The next muscle that we see here, this is the pronator tiris and this muscle that you see on the lateral side, this is the flexor carbide ulnaris. So these are the three, four superficial muscles, what I call as the PFPF. The pronator tiris, flexor carbide radialis, palmaris longus, flexor carbide ulnaris, the PFPF. Now deep to that the second layer of muscle that you see which you can see here, this is the flexor digiderm superficialis. This is the flexor digiderm superficialis and deep to that will be the three other muscles which we have not exposed here. That's the flexor digiderm profundus, flexor polysus longus and the pronator quadratus. But let's not focus on that. This is the same video as the previous one but showing the structures from a different aspect using a different camera. So this is the flexor aspect that you see under my left hand and the tendons of the flexor aspect and that's the palm and that's the extensor aspect under my right hand. We shall be talking about a few extra points about the tendons of the flexor aspect. This structure that you see under my hand, this is the flexor carbide radialis tendon. This is an important flexor of the wrist joint. This is the palmaris longus tendon. Functionally it is not so important but clinically it is useful for tendon transplants and it's also used to repair the ulnar collateral ligament when it is ruptured. This is the flexor carbide ulnaris, palmaris longus tendon which is inserted under the flexor red naquillum as you can see under my index finger. That's the pronator teres there and that is the flexor carbide ulnaris which gets inserted under the piscipomb bone. The piscipomb bone is like a seismoid bone under the flexor carbide ulnaris tendon and an extension of that is the pisohamid ligament. So a quick rule of thumb is PFPF, pronator teres, flexor carbide radialis, palmaris longus, flexor carbide ulnaris. That deep to that the next layer is the flexor digitrum superficialis, FDAS and finally the deepest layer, the third layer is the flexor digitrum profundus, pronator quadratus and flexor policies longus. The next structure that we can see on the palmar aspect or the ventral aspect of the forearm and that is this structure here. This was the bifurcation of the brachial artery in the cubital fossa and you can see it bifurcates into the radial artery and the ulnar artery and you can see it clearly here. Let's quickly trace the radial artery. This is the cut branch which was the radial recurrent artery which supplied the cube, the elbow region. Let's continue with the rest of the radial artery. This is the course of the radial artery as you can see very clearly here. This is the full course of the radial artery. The radial artery runs very close and partly under the cover of the brachior radialis muscle which you can see here. Just to digress for one second the brachior radialis gets inserted onto the radial styloid process. It's also muscle of the extensor compartment though we can see it in the flexor compartment. Let's continue. This is the radial artery and the radial artery is located just lateral to the flexor carbide radialist tendon which I told you earlier and this is where we palpate the radial artery in a living person to see whether he is alive or dead. Since we are on the radial artery itself let's continue and show you something very interesting and important about the radial artery itself. The radial artery from here it divides into a superficial branch and a deep branch and this is the deep branch that you can see here. This is the deep branch of the radial artery which I told you yesterday passes through this area which is called the anatomical snuff box and as it passes through the anatomical snuff box it pierces through the dorsal introsius muscle between the first space that is the thumb and the second finger and it goes into the palmar aspect and it forms the deep palmar arch. This is what I mentioned in the class so this is the course of the radial artery. We will not pursue the radial artery any further now let's take a look at other structures. This is the same view from a different perspective using a different camera. The radial artery arises from bifurcation of the radial artery at the lower end of the cubital fossa and you can see the origin of the radial artery. The radial artery then runs under cover partially under cover of the brachior radialis muscle on the radial side of the arm it runs on the radial side of the arm under cover of the brachior radialis muscle and that is the course of the radial artery and the brachior radialis artery is just lateral to that. When it reaches the wrist joint the radial artery divides into a deep branch and a superficial branch. I should tell you the deep branches now the superficial branch goes to the palm and it forms a superficial palmar arch by nesting with the ulnar artery which I shall tell you a little later. Let's take a look at what happens to the deep branch. The deep branch is the one which we are this is the place where we palpate the radial artery just lateral to the tendon of the flexor carbide radialis against the lower end of the radius. Let's come back to the deep branch. The deep branch then runs through the anatomical snuff box as you can see there. It runs through the anatomical snuff box and then it curves around. It pierces through the dorsal introshe of the first space and it as it pierces through and comes to the palmar aspect it gives rise to two important branches one is known as the princeps policies to the thumb and the other is the radialis indices to the index finger the radial side of the index finger and then it continues and forms the deep palmar arch which in turn gives rise to the palmar metacarpal arteries so that is the course of the radial artery and let's look at some of the other structures as we go along. The next important structure that I need to show you is the important nerve between the yes good please hold it for me like this thank you very much between the palmaris flexor carbide radialis and the palmaris longest tendon is this nerve and this is the median nerve and you can see the median nerve this is the median nerve the median nerve it the main trunk of the median nerve passes under the flexor adenoculum therefore you see it disappearing and I'm going to push my probe here and you can see it is going under the flexor adenoculum so that is the course of the median nerve the main course and as we mentioned in the class the the palmar cutaneous branch of the median nerve goes above the flexor adenoculum and it supplies the skin of the palm okay that's about the median nerve this is another view of the median nerve from a different perspective the median nerve enters the forearm by piercing through the prognitor teres muscle and the flexor digiterum superficialis muscle and near the wrist joint it comes to lie in front between the flexor carbide radialis tendon laterally and the palmaris length longest tendon medially this is an important place where anesthetics use to give digital median nerve block then the main trunk of the median nerve passes under the flexor adenoculum where my probe has gone in and here it can get trapped to form what is known as the carpal tunnel syndrome the superficial branch of the median nerve a palmar cutaneous branch it goes superficial to the flexor adenoculum and it supplies the skin of the palm therefore it is not involved in carpal tunnel syndrome let's continue further let's look at the allure division the all hear lottery the allure entry and the ulnar nerve they run undercover of the flexor carbide ulnar static and you can see them here you can see the ulnar art here and you can see the ulnar nerve here so this is the combined ulnar nerve and the ulnar artery which are running under the flexor carbide oneri standard a simple rule of thumb is that the artery is situated lateral to the nerve the ulnar artery is situated lateral to the nerve. And as we mentioned in the class, the ulnar artery enters into the palm and it anastomosis with the radial artery and it forms the superficial palmar arch. Okay. So this is about the three structures that we can see in the radio neurovascular structures here. This is another perspective of the ulnar structures. The ulnar nerve enters the forearm through the cubital tunnel near the elbow and it can get entrapped here to form the cubital tunnel syndrome. And then it runs under the cover of the flex acarpia ulnaris and it enters the palm through another small canal under the guion canal or the guion tunnel under the piezo-hamid ligament where again it can get entrapped to form the guion tunnel syndrome. The ulnar artery which runs lateral to the ulnar nerve arises from the brachial artery in the lower of the cubital fossa. It also runs under the cover of the flex acarpia ulnaris and it enters the palm superficial to the flexural redneck lip and it participates in formation of the superficial palmar arch by anastomosing with the superficial branch of the radial artery and this arch gives rise to the common and proper digital arteries. Just to bring you up to quick speed. This is the radial artery here in the wrist joint. This is the flex acarpia radial lis which is just medial to that. This is the palmaris longus and in between this is the medial nerve. This is by the way is an important site of anesthesia which anesthetists use to give a medial nerve block. These tendons are the flexed to digital superficial lis and the flex acarpia lis as we mentioned gets inserted onto the pisiform bone and under the cover of that we have the ulnar artery and the ulnar nerve. Having said that let's quickly summarize what we have seen till now going from lateral to medial near the wrist joint. We have the radial artery then the flex acarpia radial is just medial to that. Then we have the palmaris longus tendon and in between the two we have the medial nerve which is a very important landmark and then deep we have the flex of digital superficial lis tendons and then medial most we have the flex acarpia ulnaris which is inserted onto the pisiform bone. Thank you very much ladies and gentlemen for watching. Have a nice day.