 Good day everybody. This is Dr. Sanjay Sanyal, Professor, Department Chair. This is going to be a demonstration of the Petrolis Minor and the Clempe-Pectrol Triangle. Most specifically, the structures passing from the Clempe-Pectrol Triangle. This is the right side of the cadaver. I am standing on the right side. I am holding the camera. So, the structure that we see in front of us, this is the right Petrolis Major muscle, which I had already demonstrated in a separate video. We have incised this Petrolis Major muscle along its clavicular attachment and along its spectral attachment. And we shall reflect it now. So, I am holding it and I am going to reflect it. So, as I reflect it, what are the structures which come to view? We can see on the surface of the Petrolis Major and we can see these nerves coming. These are the medial pectoral nerves, the branches of the medial pectoral nerve. And we can see them in more clear detail here. They appear seeing through the Petrolis Minor muscle and they are supplying the Petrolis Major muscle. The medial pectoral nerve supplies both Petrolis Minor and Major. Now, let's focus on this portion here. This is the region of the Clempe-Pectrol Triangle. We have cleaned it out completely. We have removed all the fat-facial lymph nodes and we can see this is the cut margin of the Costa-Coroquat membrane. The Costa-Coroquat membrane forms the floor of the Clempe-Pectrol Triangle. It's a membrane which extends from the first costal cartilage and the Costa-Coroquat ligament and extends laterally up to the base of the Coroquat process, which is located deep down here. Once we remove it, we can see the following structures. We can see this here. This is the auxiliary vein. It is coming from the axilla and it is coming running under the Costa-Coroquat membrane. The next structure that we can see is these are the tributaries of the axillary vein. When I exert traction here, we can see some more structures. We can see this here. This is the lateral pectoral nerve. The lateral pectoral nerve comes from the lateral cord of the brachial plexus. It pierces through the Costa-Coroquat membrane and it supplies the Petrolis Major alone. This is used as a pedicle during pectrolis major mycutaneous flap, which I had mentioned in an earlier video. Deep down, we can see this structure here. This is the pectoral branch of the thoracochromial artery, which also pierces through the Costa-Coroquat membrane and it supplies the pectrolis major. These two structures are used as derovascular pedicles when we are doing a pectrolis major mycutaneous flap to cover a defect in the neck. So that's about the clavipectoral triangle and the contents which pierce through the Costa-Coroquat membrane. This is the clavicle up here. Other part of the Costa-Coroquat membrane is visible here. Now let's take a quick look at the pectrolis minor, which is visible under the pectrolis major. The pectrolis minor in this particular cannabar, it is taking origin from the third, fourth and fifth ribs. There can be some variations, anatomical variations in the origin. It takes origin from these ribs and it goes upwards and laterally and the fibres then get inserted onto the coracoid process. This is the place. So this is the course of the pectrolis minor. What is the action of the pectrolis minor? The pectrolis minor pulls the scapula because it gets inserted onto the coracoid process. It pulls the scapula downwards and forwards and therefore it fixes the pectrol girdle during movements of the shoulder. And we have already seen it is supplied by the media pectrol now. The branches of the media pectrol now are visible here. They pierce through the pectrolis minor, supply the pectrolis minor and then they supply the pectrolis major. This pectrolis minor, even though it's a small muscle, it has got a lot of anatomical and surgical significance. It bridges across the axilla like this, where my finger is located. And we can see it in another view here. It bridges across the axilla. And therefore it divides axillary artery into three parts. The portion proximal is called the first part from the outer part of the first strip to the media part of the pectrolis minor. The second part is behind the pectrolis minor. And the third part is from the infrolateral boundary of the pectrolis minor to the lower part of the teres major. This same pectrolis minor also divides the axillary group of lymph nodes. Those group of lymph nodes which are located deep to the pectrolis minor, they are referred to as the central group of lymph nodes which receive the lymphatics from the lateral subscapular and the pectoral group. Some people have a lymph node between the pectrolis major and the pectrolis minor. That is called rotors node or inter-pectrol node, which drains directly into the central group of lymph nodes. So these are some importance of the pectrolis minor. So that's all I wanted to show you in this particular dissection. Namely the cluster colloquial membrane which forms the flow of the clavipectro triangle and the structures piercing through and the pectrolis minor. Thank you very much for watching. This is Dr. Sanjay Sanyal, signing out. Please like and subscribe. If you have any questions or comments, please put them in the comment section below. Have a nice day.