VEINS OF THE UPPER EXTREMITY AND THORAX. 607 

 VEINS OF THE UPPER EXTREMITY AND THORAX. 



The veins of the Upper Extremity are divided into two sets, superficial and deep. 



The Superficial Veins are placed immediately beneath the integument between 

 the two layers of superficial fascia. 



The Deep Veins accompany the arteries, and constitute the venae comites of 

 those vessels. 



Both sets of vessels are provided with valves, which are more numerous in the 

 deep than in the superficial. 



The superficial veins of the upper extremity are the 



Superficial veins of the Hand. Median. 



Anterior Ulnar. Median Cephalic. 



Posterior Ulnar. Median Basilic. 



Common Ulnar. Basilic. 



Radial. Cephalic. 



The Superficial Veins of the Hand and Fingers are principally situated on the 

 dorsal surface, and form two plexuses, an inner and outer, on the back of the 

 hand. The inner plexus is formed by the veins from the little finger (vena salva- 

 tella), the ring finger, and the ulnar side of the middle finger ; from it the anterior 

 and posterior ulnar veins are derived. The outer plexus is formed by veins from 

 the thumb, the index finger, and radial side of the middle finger ; from it the 

 radial vein is derived. These two plexuses communicate on the back of the hand, 

 forming the superficial arch of veins in this situation. The superficial veins from 

 the palm of the hand form a plexus in front of the wrist, from which the median 

 vein is derived. 



The Anterior Ulnar Vein commences on the anterior surface of the ulnar side 

 of the hand and wrist, and ascends along the anterior surface of the ulnar side of 

 the forearm to the bend of the elbow, where it joins with the posterior ulnar vein 

 to form the common ulnar. Occasionally it opens separately into the median 

 basilic vein. It communicates with branches of the median vein in front and 

 with the posterior ulnar behind. 



The Posterior Ulnar Vein commences on the posterior surface of the ulnar side 

 of the wrist. It runs on the posterior surface of the ulnar side of the forearm, 

 and just below the elbow unites with the anterior ulnar vein to form the common 

 ulnar, or else joins the median basilic to form the basilic. It communicates with 

 the deep veins of the palrn by a branch which emerges from beneath the Abductor 

 minimi digiti muscle. 



The Common Ulnar i.s a short trunk which is not constant. When it exists it 

 is formed by the junction of the two preceding veins, and, passing upward and 

 outward, joins the median basilic to form the basilic vein. When it does not 

 exist the anterior and posterior ulnar veins open separately into the median 

 basilic vein. 



The Radial Vein commences from the dorsal surface of the wrist, communi- 

 cating with the deep veins of the palm by a branch which passes through the 

 first interosseous space. It forms a large vessel, which ascends along the radial 

 side of the forearm and receives numerous veins from both its surfaces. At 

 the bend of the elbow it unites with the median cephalic to form the cephalic 

 vein. 



The Median Vein ascends on the front of the forearm, and communicates with 

 the anterior ulnar and radial veins. At the bend of the elbow it receives a branch 

 of communication from the deep veins, and divides into two branches, the median 

 cephalic and median basilic, which diverge from each other as they ascend. 



The Median Cephalic, usually the smaller of the two, passes outward in the 

 groove between the Supinator longus and Biceps muscles, and joins with the 

 radial to form the cephalic vein. The branches of the external cutaneous nerve 

 pass beneath this vessel. 



