NERVES OF THE INFERIOR EXTREMITY. 



the outside of the artery, gets behind it as it ascends-, and 

 at the upper part of the thigh is on the inner side. Having 

 reached Poupart's ligament, it again changes its name, and 

 becomes the external iliac vein, which will be found described 

 along with the veins of the trunk. The popliteal receives, 

 besides the external saphena, the articular veins of the 

 knee joint. The femoral, besides the internal saphenus, 

 receives the muscular veins and veins of the profunda. 



SECTION IV. 



NERVES OF THE INFERIOR EXTREMITY. 



The source of nervous supply to the lower extremity 

 comes from the lumbar and sacral plexuses. These plexuses 

 (see Fig. 204) form two large nerves, the anterior crural, 

 and great sciatic, the origin of which, together with the 

 plexuses, are all described under the head of nerves of the 

 chest and abdomen. The branches from the lumbar plexus 

 which supply the upper part of the thigh, as the nmsculo- 

 cutaneous, genito crural, obturator, and anterior crural, have 

 also been described. 



BRANCHES OF THE ANTERIOR CRURAL NERVE. 



The cutaneous branches, four or five in number, pierce the 

 fascia lata, and from their direction upon the skin, have 

 been called the middle, external, internal and anterior cuta- 

 neous nerves. These principally supply the integuments 

 on the anterior and inner part of the thigh, some descend- 

 ing as low as the knee. 



Muscular Brandies. These are numerous to the various 

 muscles on the front, inner and outer portions of the upper 

 part of the thigh. 



The arterial branch penetrates the sheath of the femoral 

 vessels, and sends twigs which surround them. 



The internal saphenus penetrates the sheath and accom- 

 panies the femoral artery to the opening in the adductor 

 magnus. It here leaves the artery, and getting to the inner 

 side of the knee, between the tendons of the sartorius and 

 gracilis, joins the internal saphena vein, which it attends. 



