INFERIOR VENA CAVA. 847 
Superficial Veins of the Upper Arm.—Only two large superficial trunks, 
the basilic and the cephalic, are found in the upper arm. 
The basilic vein (v. basilica) commences at the upper and inner part of 
the bend of the elbow by the union of the median basilic with the posterior ulnar 
vein. It ascends in a groove along the inner border of the biceps to the middle of 
the upper arm, where it passes through an opening in the deep fascia, the hiatus 
semilunaris, and in the rest of its course lies deeply along the inner side of the 
brachial artery. It terminates at the lower border of the teres major by becoming 
the axillary vein, and it contains one or more bicuspid valves. 
The cephalic vein (vy. cephalica) is formed at the upper and outer part 
of the bend of the elbow by the union of the radial vein with the cephalic 
branch of the median vein. It ascends first along the outer border of the biceps, 
where it is accompanied by the superior external cutaneous branch of the musculo- 
spiral nerve; then, after piercing the deep fascia, it is continued upwards between 
the adjacent borders of the deltoid and pectoralis major muscles, accompanied by 
the descending or humeral] branch of the acromio-thoracic axis. Just below the 
clavicle it turns inwards, pierces the costo-coracoid membrane, and terminates in 
the upper or third part of the axillar y vein. It is provided with a bicuspid valve 
at its termination. In its primitive form it terminated in the external jugular 
vein, to reach which it passed either over or through the clavicle. This condition 
occasionally persists, or is represented by a small communicating vein. 
THE INFERIOR VENA CAVA AND ITS TRIBUTARIES. 
The inferior vena cava (Fig. 587) is a large venous trunk which receives the 
whole of the blood from the lower extremities, and the greater part of the blood 
from the walls and contents of the abdomen and pelvis. It commences opposite 
the right side of the body of the fifth lumbar vertebra, behind and to the right of 
the right common iliac artery, ascends through the al ,domen in front and to the 
right of the vertebral column and the right erus of the diaphragm, and pierces 
the cupola of the diaphragm, between the middle and ri ight sections of the central 
tendinous leaflet, at the level of the eighth dorsal vertebra. It then enters the 
middle mediastinum, passes through the pericardium, and terminates in the lower 
and back part of the right auricle. Its intrapericardial portion is very short, and 
it is covered on its anterior and lateral aspects by the parietal portion of the 
serous layer. Attached to the lower and front margin of its auricular orifice is 
the Eustachian valve, which is a remnant of an important fold of endocardium by 
which, in the foetus, the blood from the inferior vena cava is directed, through the 
foramen ovale, into the left auricle. 
Relations.—The inferior vena cava is in relation behind with the bodies of the 
lower lumbar vertebree and the corresponding part of the anterior common ligament, the 
anterior portion of the right psoas muscle, the right lumbar sympathetic cord, the roots 
of the right lumbar arteries, the right crus of the diaphragm, the right renal artery, the 
right semilunar ganglion, the right inferior phrenic artery, and the inner and upper 
portion of the right suprarenal body. 
In front of it, from below upwards, are the following structures—the right common 
iliac artery, the lower end of the mesentery and the superior mesenteric artery, the 
spermatic artery and the third part of the duodenum, the head of the pancreas, the 
portal vein and the first part of the duodenum, the foramen of Winslow, and the posterior 
surface of the liver. More superficially are coils of small intestine, the great omentum, 
and the transverse colon and mesocolon. 
To its left side are the aorta and the right crus of the diaphragm. 
On its right side and below is the right ureter, whilst at a higher level the right 
kidney is only separated from it by a short interval. 
Tributaries.—In addition to the two common iliac veins, by the union of which it is 
formed, and through which it receives blood from the pelvis and from the lower extremi- 
ties, the inferior vena cava receives the following tributaries :—The hepatic veins, the 
right inferior phrenic vein, the right suprarenal vein, the right and left renal veins, the 
right spermatic or ovarian vein, and the right and left lumbar veins. 
