EXTERNAL ILIAC 647 



tlie vein j)ays('S throut^li Hunter's canal, it lies luiiind ami a little external to the 

 artery. At the apex of Scarpa's triangle it is still jjosterior to the artery, but 

 gradually passes to the inner side as it ascends through tliat space. It contains 

 three pairs of valves. The close connection of the vein to the artery should 

 be renieinljered in tlie operation of ligature. The sheath should be ojjened on its 

 inner side, that is, well over the artery, and the point <»f the aneurysm needle kept 

 closely a])plied to the artery lest it perforate the overlai>ping vein. 



Tributaries. — (1) The venae comites of the anastoniotica magna artery; (2) 

 the venfe coniit(^s corn'S])onding to the muscular branches of the femoral. 



The profunda or deep femoral vein accompanies the profunda or deep femoral 

 artery, and receives the venic comites corresponding to its various branches. 

 Unlike the other veins of the lower extremity, it lies in front of its companion 

 artery, and is at first a little internal to it. It terminates by joining the super- 

 ficial femoral vein about an inch and a half below Poupart's ligament in the angle 

 between the femoral and profunda arteries. It contains five valves. 



The common femoral vein is a short thick trunk corresponding to the common 

 femoral artery. It is formed by the confluence of the su])erficial femoral and 

 jirofunda veins about an inch and a half below Poupart's ligament, and is con- 

 tinued upwards to the lower border of that structure, where it takes the name 

 of external iliac. It lies on the same plane as the common femoral artery, but 

 internal to that vessel, from which it is separated by a delicate prolongation 

 of fascia stretching between the front and back layers of the femoral sheath. 

 Internally, it is separated by a similar septum of fascia from the crural canal. 

 It usually contains two valves: one just above the junction with the profunda vein, 

 the otlier just below Poupart's ligament (fig. 372). 



Tributary. — The long saphenous vein which reaches it by passing through the 

 sai)hcuous opening in the deep fascia. 



Chief variations. — (1) The femoral vein luay be double in part or in the whole of its length. 

 (2) It may sjilit into two and embrace the femoral artery. (3) It may pass through the 

 adductor magiius above the femoral artery and run separate from the artery until it joins the 

 ])rofunda vein to form the common femoral vein. (4) It may run with the sciatic neiTe and 

 pierce the adductor magnus at tlie level of the lesser trochanter. When this occurs the femoral 

 artery is usually very small, and the sciatic artery is the chief nutrient vessel of the thigh. 



The external iliac vein is the continuation upwards of the common femoral. 

 Beginning at the lower border of Poupart's ligament it accompanies the external 

 iliac artery upwards and inwards along the brim of the pelvis, lying at first on tlie 

 horizontal ramus of the pubes, and then on the psoas muscle. It terminates in the 

 common iliac vein by joining the internal iliac vein behind the internal iliac artery 

 opposite the lower border of the sacro-iliac synchondrosis. It lies at first internal 

 to the external iliac artery, and on the left side remains internal to the artery 

 throughout its course. On the right side, however, as it ascends, it gradually gets 

 a little behind the artery. It contains one or two valves. 



Tributaries. — (1) The deep epigastric vein, formed by the union of the veiue 

 comites of the deep epigastric artery, joins the external iliac just above Poupart's 

 ligament. (2) The deep circumflex iliac vein, which is formed in the same way 

 by the confluence of the vente comites of the deep circumflex iliac artery, joins the 

 external iliac vein a little higher. 



