INTERNAL SAPHENOUS VEIN. 139 



Dissection. After having observed the disposition of the super- Dissection 



i * T- j i i i . of the front 



ncial fascia near Pouparts ligament, the student may proceed to O f the thigh, 

 examine the remainder of the subcutaneous covering of the thigh, 

 together with the vessels and nerves in it. 



To raise the skin from the front of the thigh, a cut is to be Take away 

 carried along the centre of the limb, over the knee-joint, to rather the skm> 

 below the tubercle of the tibia. At the extremity of this a trans- 

 verse incision is to be made across the front of the leg, but this is 

 to reach farthest on the inner side. The skin may be reflected in 

 flaps inwards and outwards ; and as it is raised from the front of 

 the knee, a superficial bursa between it and the patella will be 

 opened. 



The saphenous vein is to be first traced out in the fat as far as nd follow 

 the skin is reflected, but in removing the tissue from it the student ^{ n . 

 should be careful of branches of the internal cutaneous nerve. 



The cutaneous nerves of the front of the thigh (fig. 55, p. 140) Seekcutane- 

 are to be sought in the fat, with small cutaneous arteries, in the of S frontof 

 following positions : On the outer margin, below the upper third, thigh, 

 is placed the external cutaneous nerve. In the middle of the limb, 

 below the upper third, lie the two branches of the middle 

 cutaneous nerve. At the inner margin are the ramifications of the 

 internal cutaneous nerve one small offset appearing near the upper 

 part of the thigh, one or more about half-way down, and one of the 

 terminal branches (anterior) about the lower third. 



On the inner side of the knee three other cutaneous nerves are to and on side 

 be looked for : One, a branch of the great saphenaus, is directed 

 outwards over the patella. Another, the trunk of the great saphe- 

 nous nerve, lies by the side of the vein of the same name, close to 

 the lower edge of the surface now dissected. And the third is a 

 terminal branch (posterior) of the internal cutaneous nerve, which 

 is close behind the preceding, and communicates with it. 



VESSELS. All the cutaneous veins on the anterior and inner as- Superficial 

 pects of the thigh are collected into one ; and this trunk is named ^ eim>- 

 saphenous from its manifest appearance on the surface. 



The INTERNAL SAPHENOUS VEIN (fig. 54, a) IS the CUtaneOUS Internal 



trunk of the inner side of the lower limb, and extends from the ve i n m 



foot to the top of the thigh. In the part of its course now dis- thi s h 



sected, the vessel lies inferiorly somewhat behind the knee-joint ; 



but as it ascends to its termination, it is directed along the inner 



side and the front of the thigh. Near Poupart's ligament it pierces pierces 



the fascia lata by a special opening named saphenous, and enters to join the 



the deep vein (femoral) of the limb. femoral. 



Superficial branches join it both externally and internally ; and Veins join- 

 near Poupart's ligament the three veins corresponding with the ins 

 arteries in that situation, viz., superficial external pudic, superficial 

 epigastric, and superficial circumflex iliac, terminate in it. Towards may be 

 the upper part of the limb the veins of the inner side and back of B t tho top of 

 the thigh are frequently united into one branch, which enters the the thl s h < 

 saphenous trunk near the aperture in the fascia lata ; and some- 

 times those on the outer side of the thigh are collected together in 



