 Good day everybody. This is Dr. Sanjay Sanyal from the department chair. This is a supine cadaver. This is the right forearm In the prone position. We are showing the dorsal aspect. I'm standing on the right side, and I am holding the camera Many of you have asked me to show you a superficial dissection showing the cutaneous nerves So let's take a look at the structures that we can see them in this preliminary dissection We can see this spelling here. This is the lateral epicondyle And we can see this muscle taking origin from just above the lateral epicondyle. This is the brachioradialis In this particular cadaver, there is an accessory slip of the brachioradialis Which is taking origin from higher up and as a matter of fact it is merging with the triceps And not only that lower down the same extra slip is merging with the brachioradialis The brachioradialis is actually a muscle extensor compartment. Though it is located at the Junction between the extensor and the flexor and it forms also the boundary of the pivotal fossa Now if you were to take a close look, you will find there's a nerve which is running just under the brachioradialis And that nerve is this one which I have picked up here This is the cutaneous superficial division of the radial nerve The main radial nerve is located here and we can see it here This is the main radial nerve It is giving a superficial cutaneous branch Which is running and as it runs distally it pierces Under the brachioradialis and it comes from the dorsal aspect. To continue with where we had started This was the lateral epicondyle. This is the common extensor origin and coming from this is all the extensor muscles on the forearm We can see that they're all covered by this whitish structure here. This is the anti-brachial fascia This anti-brachial fascia covers all the extensor muscles and as it goes distally We can see it becomes thickened and it forms a separate layer And the fibers are running From lateral to medial in an oblique fashion This portion of the fiber this is referred to as the extensor reticulum of the wrist So what is this extensor reticulum and what does it do? Laterally it takes attachment from the radius Many people think that medially it gets attached to the ulna. No It cannot get attached to the ulna because if it had been attached to the ulna It would have been impossible for us to do pronation and supination That's the reason why these fibers they go obliquely They go medially and they get inserted onto the carpal bones specifically in the bisiform bone The purpose of this is to prevent post training of the extensor tendons That means when we do dorsiflexional hand these tendons will have a tendency to lift up like a post strain And that is prevented by the midst of this extensor reticulum This extensor reticulum it is attached to many bony prominences, especially the dorsal tubicle of lister on the dorsal aspect of the radius And therefore it converts the lower portion under this Extensor reticulum into multiple compartments six compartments to be precise And running through each of these compartments will be a group of tendons Which I shall tell you in more detail when I open up this section, but we can see the tendons running here So that is about this extensor reticulum, which is the continuation of the anti-brachial fascia and distally the anti-brachial fascia continues onto the dorsal of the palm as the dorsal fascia of the palm The next structure I will draw your attention to as I mentioned earlier is the cutaneous superficial branch of the Radial nerve We can see it is coming from under the brachioradialis And here it is Breaking up into two branches one branch is going towards the thumb and the other branch is going towards the dorsal of the palm The next structure I will draw your attention to is this nerve which I have taken out This is the dorsal cutaneous branch of the ulnar nerve It was on the ulnar aspect, but we brought it out to the dorsal aspect to show you that it supplies the dorsal of the hand The medial one-fourths of the dorsal of the hand So this is the dorsal cutaneous branch of the ulnar nerve The next point I will draw your attention to are these cutaneous branches Which we have cut and lifted up these are the cutaneous branches which supply the dorsal of the hand and which go to the digits from the dorsal aspect So these are the structures which I want you to bring your attention to in this superficial preliminary action And as we go further we will reset out the external serrat necrolum And we will also take out the anti-brachial fascia and we will see the individual muscles And we shall see all the six compartments under the external serrat necrolum And then we shall go to the dorsal of the hand Thank you very much for watching stay tuned for the next video Please like and subscribe if you have any questions or comments, please put them in the comment section below Have a nice day. Dr. Sanjay Sanyal signing out