568 DISSECTION OF THE THIGH. 



knee and hip-joints over which it passes, giving rise to rotation inwards 

 of the tibia ; and makes tense finally the fascia of the thigh. 



With the limbs fixed, the two muscles will support the pelvis in stand- 

 ing, and will assist in bringing forwards the pelvis in stooping and 

 walking. 



When standing on one leg the muscle will help to rotate the body, so as 

 to turn the face to the opposite side. 



Dissection (fig. 197). The sartorius is to be turned aside, or cut 

 through if it is necessary, to follow the remaining part of the femoral 

 artery. 



Beneath the muscle is an aponeurosis between the adductor and exten- 

 sor muscles ; this is thin above, and when it is divided the internal saphe- 

 nous nerve will come into view. Parallel to the upper part of the saphe- 

 nous nerve, but outside it, is the nerve to the vastus internus muscle, 

 which sends an offset on the surface of the vastus to the knee-joint ; this 

 may be traced now, lest it should be destroyed afterwards. The plexus 

 of nerves on the inner side of the thigh may be more completely dissected 

 in this stage. 



The femoral vessels and their branches are to be nicely cleaned. Where 

 the femoral artery passes to the back of the limb its small anastomotic 

 branch arises : this branch is to be pursued through the fibres of the vastus 

 internus, and in front of the adductor magnus tendon to the knee ; an off- 

 set of it is to be followed with the saphenous nerve. 



The aponeurotic covering over the femoral vessels (fig. 197, 7 ) exists 

 only where these are covered by the sartorius. It is thin above, but below 

 it is formed of strong fibres, which are directed transversely between the 

 vastus internus and the tendons of the adductor muscles. Inferiorly the 

 membranous structure ceases at the opening in the adductor magnus by a 

 defined border, beneath which the saphenous nerve and its vessels escape. 



The deep part of the femoral artery (fig. 197, *) lies in a hollow be- 

 tween muscles (Hunter's canal) until it reaches the opening in the adduc- 

 tor magnus. Here it is covered by the sartorius muscle and the subjacent 

 aponeurosis, in addition to the integuments and the superficial and deep 

 fasciae. Beneath it are the pectineus, the adductor brevis in part, the 

 adductor longus, and a small piece of the adductor magnus. On the outer 

 side is the vastus internus. 



External to the artery and close to it is the femoral vein ; and in the 

 integuments oftentimes an offset of the saphenous passes across the line of 

 the arterial trunk. 



Crossing over the artery from the outer to the inner side is the internal 

 saphenous nerve, which is beneath the aponeurosis before noticed, but is 

 not contained within the areolar sheath of the vessels. 



Splitting of the artery. Occasionally the femoral artery is split into two below 

 the origin of the profunda. Four examples of this peculiarity have been met 

 with ; but in all, the trunks were blended into one above the opening in the 

 adductor muscle. 



Branches. One named branch, anastomotic and muscular offsets, spring 

 from this part of the artery. 



The anastomotic branch (fig. 198, &) (arter. anastomotica magna) arises 

 close to the opening in the adductor muscle, and divides at once into two 

 parts, superficial and deep : 



The superficial offset () continues with the saphenous nerve to the 



