 going to be a demonstration of the structures on the dorsum of the foot. This is the entry aspect of the leg. This tendon that I picked up here, this is the tibialis anterior tendon and we can see it goes all the way and it gets inserted onto the medial cuneiform at the base of the first menotarsis. This is a very powerful dorsiflexor of the foot. The next tendon that we can see here is this one here. This is the extensor halosus longus and we can see it is going all the way to the distal phallus of the great toe. The next tendon or the group of tendons that we can see here is this one which I have lifted up here. This is the extensor digital longus and we can see the tendons going individually to the little toe, next toe, this and the second toe. The fourth tendon that we can see on the lateral aspect which starts in continuity with the extensor digital longus but it separates off. This is the fibularis tercius and if you look closely the fibularis tercius has got multiple slips here which get inserted onto the base of the fifth metatarsal. So therefore this is the extensor of the great toe. These are the extensors, long extensors of the other toes and the fibularis tercius is a weak inverter of the foot. These were all enclosed in the extensor red necrolum of the ankle joint and we have removed the extensor red necrolum to show the tendons. These are all muscles of the anterior compartment and they're all supplied by the deep fibular nerve. Let me continue now from the lateral compartment of the leg. I have lifted up this tendon here and under that there is yet one more tendon. So this is the fibularis longus and this is the fibularis brevis. Both of these are in the lateral compartment and this is the lateral compartment. Both of them go behind the lateral malleolus. Fibularis longus we cannot see because it goes deep to the sole of the foot and it comes here. It gets attached again to the medial uniform and the base of the first metatarsal, same as the tibialis anterior but from the opposite side. Therefore this is an inverter of the foot but we cannot see the rest of the tendon. Let's take a look at the fibularis brevis. The fibularis brevis also runs behind the lateral malleolus and they are bridged over by this tissue structure here. This is the peroneal or the fibular reginoculum. That's what prevents them from slipping forward and if we trace we see that there's a tendon continuing forward and when I lift it up here this is the fibularis brevis. Again I will show you the fibularis brevis from this side and I'm going to lift it up here. So this is the fibularis brevis. The fibularis brevis goes and gets inserted onto the tuberosity of the fifth metatarsal bone. So this is also an inverter of the foot. In this connection I want to mention a very important clinical correlation which is not very uncommon and that is called Dancer's fracture. When the fibularis brevis is contracting the foot is in a state of eversion. In that moment if the foot is forcibly inverted there is traction exerted on the tuberosity of the fifth metatarsal and can lead to abortion fracture of the tuberosity of the fifth metatarsal and that is known as Dancer's fracture. So just to bring up to speed the base of the fifth metatarsal gives insertion to two tendons. One is the fibularis brevis here and the other is the fibularis tertius here. The difference being fibularis tertius is a weak inverter, fibularis brevis is a strong inverter. Fibularis tertius belongs to the anterior compartment, fibularis brevis belongs to the lateral compartment. Fibularis tertius is supplied by the deep fibular nerve, fibularis brevis is supplied by the superficial fibular nerve which we can see here. So having mentioned the long tendons now let's take a quick look at the nerves. We can see these nerves coming out from here on the lateral aspect. We can see two of those fibbers here. These are the branches of the superficial fibular nerve. They supply the muscles of the lateral compartment, then they pierce the fascia. We can see the fascia here, the crural fascia and by means of multiple branches they come to the dorsum of the foot and some of those branches have been retained here but most of them have been cut and they supply the skin of the entire dorsum of the foot except this portion here. Person who supports from repeated inversion injury of the foot, they can get traction neuropathy of the superficial fibular nerve and we can see the superficial fibular nerve. The point to be remembered is the superficial fibular nerve does not go under the extensors reticulum, it goes superficial and it supplies most of the skin and in a thin person you can even see the fibbers because they are located rather superficial and we can see the fibbers superficially. And they can be used to give anesthesia to anesthetize the whole large part of the dorsum of the foot. Now let's take a look at the other neurovascular structures coming from the anterior compartment of the leg. We are between the TBL's anterior and the extensor helices longus and I have lifted up the neurovascular structures here. This is the deep fibular nerve and just adjacent to that is the anterior TBL artery. So we can see the anterior TBL artery here and we can see the deep fibular nerve here. In the beginning it's between the TBL's anterior and the extensor helices longus but as they go down both these structures they come lateral to the extensor helices longus and we can see that here. So this is the extensor helices longus and they have come laterally and we can see this is the deep fibular nerve now and this is the anterior TBL artery. So they are both located lateral to the extensor helices longus. The deep fibular nerve you can see it is disappearing under the extensor reticulum and this is the terminal part of it. So it goes under the extensor reticulum of the ankle and then it continues and it supplies the two muscles on the torso of the foot which I shall describe just now and thereafter it continues and it supplies the skin of the first interdigital cleft only. So that is the full course of the deep fibular nerve. What about the anterior TBL artery and the vein? The anterior TBL artery in the vein they give rise to a medial malular branch and a lateral malular branch and we can see the lateral malular branch here. I have lifted it up here. It's coming to the lateral malulus. Then it continues. It runs with the deep fibular nerve and here it is known as the dorsal asperis artery and this is where we can feel the pulsation of the anterior TBL artery but here it is dorsal asperis just lateral to the extensor helices longus tendon against the navicular bone and this is clinically used to feel the dorsal asperis pulse and thereafter it gives dorsal branches and RQA artery and that's how it terminates. So having mentioned all the neurovascular structures now let me show you the two muscles on the dorsal aspect. Under this these long tendons was a fascia and that is known as the dorsal fascia which we have removed and to show the muscles and let's take a look at the muscle. I have lifted up the medial margin of one muscle here. This is one margin of the muscle here and if you look closely this is the lateral margin of the other muscle here. So this muscle that we see here this is the extensor helices brevis and we can see the tendon is running under the extensor helices longer tendon. So this is extensor helices brevis. Then we have another muscle which is just lateral to that this muscle that we see here where my instrument is moving. This is the extensor digitorum brevis. The extensor digitorum brevis gives four slips and we can see each of these slips are going under the respective extensor helices longer tendon. So this is one slip. It is going to the second toe. Then we have yet another slip. This is going to the third toe. We have another slip going to the fourth toe and there will be another slip going to the fifth toe. So this is the extensor digitorum brevis. So these two muscles are unique that they are not present in the hand but they're present in the foot and this was the one which is present in the dorsal compartment of the foot. These two muscles are supplied by this nerve which I mentioned just a little while back namely the deep fibular nerve. Compression of the deep fibular nerve inside the extensor red necrolum which is called ski boots syndrome. There will be weakness of these muscles. Extensor helices brevis and extensor digitorum brevis and there will be numbness tingling and peristicia in the first interdigital cleft. So these are the structures which I wanted to show you in the dorsum of the foot and a little bit of the lateral aspect of the foot. Thank you very much for watching. Dr. Sanjay Sanyal signing out. MD1 students are my assistants. If you have any questions or comments please put them in the comment section below. Have a nice day.