 Good day everybody. This is Dr. Sanjay Sangal, Professor, Department Chair. This is a quick demonstration of the posterior tibial artery and the pest anserinas. We have cut tendocalcaneus, and I have reflected it up. We can see this vessel here. This is posterior tibial artery with its accompanying vinae cometantis. Vinae cometantis are accompanying veins of the arteries which are seen in the leg and in the hand. These vinae cometantis are the ones which circulate the venous blood up and they use the arterial pulsation to transmit the blood up. I'm going to put my hand under the soleus and you can see it is coming out here. This location is referred to as the tendinous arch of soleus. It is a fibrotic arch which stretches from the tibia to the fibula, to which the soleus muscle is attached. And this tibial nerve and the popliteal artery and the popliteal vein, they pass through that. So this is another potential site of obstruction of the popliteal artery. So therefore to summarize, a doctor hiatus, medial head of the gastrochemius, tendinous arch of soleus. These are the three potential sites of obstruction of the popliteal artery. At the tendinous arch of soleus, the popliteal artery divides into a posterior tibial and anterior tibial. The posterior tibial is the one which we can see here. It gives a branch which we can see. This is the fibular branch. The posterior tibial then continues down and it enters into the foot and it forms the medial and lateral plantar arteries. The posterior tibial and the fibular artery, they give mostly bony branches. They give nutrient arteries to the tibia, fibular respectively, medial and lateral malleolar and the calcaneal branches. This is the leg angiogram to show the branches of the popliteal and the tibial arteries in the leg. I have put three muscles together below the knee and we can see a structure here when I lift these three tendons up. This structure that we can see here, this is referred to as the pest anserinas. The word pest anserinas in Latin literally means the foot of a goose and if you look very carefully, it somehow resembles the foot of a goose. Pest anserinas is composed of the combined insertion of three muscles, one each from each of the compartments of the thigh. The first is this muscle here. This is the sartorius which was running like this and we can see it. I have separated it out here and brought it in front. So this is the sartorius. This is from the anterior compartment. In the next muscle, this is the graceous which is the muscle of the medial compartment. And this tendon, this is the semi tendonosis which is the muscle of the posterior compartment. These three muscles together constitute the pest anserinas insertion on the upper medial aspect of the tibia. And under the pest anserinas, there is a bursar which is referred to as the ancerine bursar. And if you were to look under the pest anserinas, we can see a tough ligament here which has been interpreted up by my instrument. This is the tibial collateral ligament. So there is a pest anserinas ancerine bursar between these two and there can be a bursar under the tibial collateral ligament between the ligament and the medial surface of the tibia.