 So this is going to be a demonstration of the leg, the anterior compartment and the lateral compartment. So to bring up to speak, my finger is tracing along the anterior border of the tibia. This is the left leg and this is the medial surface of the tibia and behind this is the medial border of the tibia. The medial surface of the tibia is subcutaneous. Attached to the anterior border is the trural fascia and part of that we have retained here. This is the fibula. And attached to the anterior border of the fibula, we can see this is the remnant of the trural fascia again here. So the anterior compartment is between this layer of trural fascia and this layer of trural fascia which I have lifted up with both my hands. This flat membrane that we see here, this is the anterior intramuscular symptom which separates the anterior compartment from the lateral compartment. So this is the anterior compartment. The anterior compartment is the extensor compartment of the leg and the muscles that we can see here are going from medial to lateral. First is this muscle which we have lifted up here. This is a very powerful muscle and we can see this strong tendon here. This is the tibialis anterior which is the most powerful dorsiflexor of the foot and paralysis of this will produce foot trauma. This is inserted onto the medial cutiform and the first menodarsal bone on the medial side. The next muscle that we can see just next to that lateral to that is this one here. This is the extensor halosis longus. Then we have this combined tendon and muscle. These are the tendons of the extensor digitorum longus. And the lateral most fibers of the extensor digitorum longus are the fibularis tercius which we will be able to see more clearly on the dorsum of the foot. So these are the four muscles that we can see in the anterior compartment. And as the term implies, the extensor halosis longus extends the great toe, extends the digitorum longus, extends the other toes and the fibularis tercius is a weak inverter of the foot. Now let's take a look at the neurovascular structures in the anterior compartment. And I have separated the tibialis anterior and extensor halosis longus. And we can see the neurovascular structure and I shall pick them up just now. These are the neurovascular structures which I have lifted up here. So this is the anterior tibial artery and this is the deep fibular nerve. The anterior tibial artery is the smaller terminal division of the corporeal artery. It comes in front of the interosseous membrane. And we can see the anterior tibial artery is accompanied by its venae comitantes. It runs down and it supplies the muscles of the anterior compartment. This is the deep fibular nerve. The deep fibular nerve supplies all the muscles in the anterior compartment and then it continues under the extensor adneculum onto the dorsum of the foot. Now let's continue further. This is again one part of the crural fascia which is attached to the anterior border of the fibula. And this is another part of the crural fascia which is attached to the posterior border of the fibula. So this is the anterior intramuscular septum and behind that this is the posterior intramuscular septum. Between the anterior border of the fibula and the posterior border of the fibula we have the lateral compartment of the leg. In the lateral compartment we have two muscles. The two muscles are first this tendon which I picked up here. This is the fibularis longus which takes origin from the upper end of the lateral surface of the fibula. And under that we have this tendon here. This is the fibularis brevis. The fibularis brevis takes origin from the lateral surface of the fibula below under the fibularis longus. And we can clearly see now I have lifted up both. This is the fibularis longus and this is the fibularis brevis. Both the tendons run behind the lateral valueless and their insertion is in the foot which we shall describe later. Now let's take a look at the neurovascular structure here. Once I reflect this fascia we can see this nerve here. This is the superficial fibular nerve. The superficial fibular nerve is the smaller terminal division of the common fibular which I shall show just now. And this is the one which supplies the muscles of the lateral compartment. And after it is supplied the muscles of the lateral compartment we can see it is piercing through the cruel fascia. And we can see one branch going down here and we can see another branch also piercing the cruel fascia. And they then supply by means of multiple branches they supply the skin of the lower antrilateral one third of the leg. And a large part of the skin of the dorsum of the foot. And we can see the cutaneous branches here. So that brings me to the origin of these two nerves. The superficial fibular nerve which I showed and the deep fibular nerve which I have lifted up now. Both these nerves come from this nerve here. So if we were to move up above the knee we can see this nerve here. This is the common fibular nerve. The common fibular nerve runs under cover of this muscle here. This is the biceps femoris which is a muscle of the posterior compartment of the thigh. And we have retracted it to show the common fibular nerve. Biceps femoris tendon gets inserted onto the head of the fibula. And then the common fibular nerve it goes behind the head of the fibula. This is the head of the fibula. And then it winds around the lateral aspect of the neck of the fibula. We cannot see the neck of the fibula because it is covered by the fibularis longus muscle. It goes deep to the fibularis longus muscle. And there it divides into the superficial fibular nerve. And it divides into the deep fibular nerve. The superficial fibular nerve supplies the lateral compartment. The deep fibular nerve supplies the anterior compartment. Mentioning a few words of clinical correlation at this juncture. Fracture of the neck of the fibula can damage the common fibular nerve. And then it will produce paralysis of the deep and the superficial fibular branches. The most important disability will be paralysis of the tibialis anterior and foot drum. That is one important, very important clinical correlation. The deep fibular nerve runs under the extrinsic reticulum. And here it can get entrapped in a condition known as ski boots syndrome. A person who suffers from repeated inversion injury can get traction neuropathy of the superficial fibular nerve. Person who gets a blunt trauma to the front of the leg, the muscles can get swollen up. And they are tightly enclosed within this osteofacial compartment, which I mentioned in the beginning, namely the trural fascia in front, the introsius membrane behind and the two bones on either side. This type of osteofacial compartment prevents swelling of these muscles and therefore they can lead to compression of the neurovascular structures here, leading to what is known as compartment syndrome. In such case, the immediate treatment should be to do what we have done in this dissection, split open the trural fascia and let the muscle expand. And that treatment is known as fasciotomy. So these are some of the points which I want to mention about the structures in the anterior compartment of the leg and the lateral compartment of the leg. Thank you very much for watching Dr. Sanjay Sanyal signing out. David, who is the camera person? If you have any questions or comments, please put them in the comment section below. Have a nice day.