FEMORAL. 521 



the coats of the vessel may be interfered with, or muscular branches which arise from the ves- 

 sel at irregular intervals may be divided. In this part of the operation, a small nerve which 

 crosses the sheath should be avoided. The anuerism needle must be carefully introduced, and 

 kept close to the artery, to avoid the femoral vein, which lies behind the vessel in this part of 

 its course. 



To expose the artery in the middle of the thigh, an incision should be made through the in- 

 tegument, between three and four inches in length, over the inner margin of the Sartorius, 

 taking care to avoid the internal saphenous vein, the situation of which may be previously 

 known by compressing it higher up in the thigh. The fascia lata having been divided, and the 

 Sartorius muscle exposed, it should be drawn outwards, when the strong fascia, which is 

 stretched across from the Adductors to the Vastus Internus, will be exposed, and must be freely 

 divided ; the sheath of the vessels is now seen, and must be opened, and the artery secured by 

 passing the aneurism needle between the vein and artery, in the direction from within outwards. 

 The femoral vein in this situation lies on the outer side of the artery, the long saphenous nerve 

 on its anterior and outer side. 



It has been seen that the femoral artery occasionally divides into two trunks, below the origin 

 of the profunda. If, in the operation for tying the femoral, two vessels are met with, the sur- 

 geon should alternately compress each, in order to ascertain which vessel is connected with the 

 aneurismal tumor, or with the bleeding from the wound, and that one only should be tied which 

 controls the pulsation or hemorrhage. If, however, it is necessary to compress both vessels 

 before the circulation in the tumor is controlled, both should be tied, as it would be probable 

 that they became reunited, as in the four instances referred to above. 



Collateral Circulation. When the common femoral is tied, the main channels for carrying 

 on the circulation are the anastomoses of the gluteal and circumflex iliac arteries above with 

 the external circumflex below; of the obturator and sciatic above with the internal circumflex 

 below; of the ilio-lumbar with the external circumflex, and of the comes nervi ischiadici with 

 the arteries in the ham. 



The principal agents in carrying on the collateral circulation after ligature of the superficial 

 femoral artery are, according to Sir A. Cooper, as follows : ' 



"The arteria prot'uuda formed the new channel for the blood." "The first artery sent off 

 passed down close to the back of the thigh-bone, and entered the two superior articular branches 

 of the popliteal artery." 



" The second new large vessel arising from the profunda at the same part with the former, 

 passed down by the inner side of the Biceps muscle, to an artery of the popliteal, which was 

 distributed to the Gastrocnemius muscle ; whilst a third artery, dividing into several branches, 

 passed down with the sciatic nerve behind the knee-joint, and some of its branches united them- 

 selves with the inferior articular arteries of the popliteal, with some recurrent branches of those 

 arteries, with arteries passing to the Gastrocnemii, and, lastly, with the origin of the anterior 

 and posterior tibial arteries." 



"It appears, then, that it is those branches of the profunda which accompany the sciatic 

 nerve, that are the principal supporters of the new circulation." 



In Porta's work 2 (Tab. xii. xiii.) is a good representation of the collateral circulation after the 

 ligature of the femoral artery. The patient had survived the operation three years. The lower 

 part of the artery is, at least, as large as the upper ; about two inches of the vessel appear to 

 have been obliterated. The external and internal circumflex arteries are seen anastomosing by 

 a great number of branches with the lower branches of the femoral (muscular and anastomotica 

 magna). and with the articular branches of the popliteal. The branches from the external cir- 

 cumflex are extremely large and numerous, one very distinct anastomosis can be traced between 

 this artery on the outside, and the anastomotica magna on the inside, through the intervention 

 of the superior external articular artery with which they both anastomose, and blood reaches even 

 the anterior tibial recurrent from the external circumflex by means of an anastomosis with the sam ; 

 external articular artery. The perforating branches of the profunda are also seen bringing blood 

 round the obliterated portion of the artery into long branches (muscular) which have been given 

 off just below that portion. The termination of the profunda itself anastomoses, most freely 

 with the superior external articular. A long branch of anastomosis is also traced down from 

 the internal iliac by means of the comes nervi ischiadici of the sciatic which anastomoses on the 

 popliteal nerves with branches from the popliteal and posterior tibial arteries. In this case the 

 anastomosis had been too free, since the pulsation and growth of the aneurism recurred, and the 

 patient died after ligature of the external iliac. 



There is an interesting preparation in the Museum of the Royal College of Surgeons, of a 

 limb on which John Hunter had tied the femoral artery fifty years before the patient's death. 

 The whole of the superficial femoral and popliteal artery seems to have been obliterated. The 

 anastomosis by means of the comes nervi ischiadici, which is shown in Porta's plate, is distinctly 

 seen ; the external circumflex, and the termination of the profunda artery, seem to have been the 

 chief channels of anastomosis; but the injection has not been a very successful one. 



Branches. The branches of the femoral artery are the 

 Superficial epigastric. 

 Superficial circumflex iliac. 



1 Med.-Chir. Trans., vol. ii. 1811. 2 Alterazioni patologiche delle Arteris. 



