VEINS OF THE UPPER EXTREMITY. 



889 



be performed. The resulting swelling and oedema of the upper limb are minimized 

 by the consecutive enlargement of the cephalic vein. Such swelling and oedema are 

 common symptoms of pressure upon the axillary vein by cancerous lymph-nodes in 

 the later stages of mammary cancer (page 770). Suture of the wall of the vein in 

 cases of accidental and of operative wound has been successfully performed. 



Olecranon 



External condyl 



Cephalic vein 



THE SUPERFICIAL VEINS. 

 The Superficial Veins of the Hand. 



The veins upon the dorsal surface (Fig. 763) form the principal superficial 

 channels for the return of blood from the hand. They begin in a plexus upon the 

 dorsum of the first phalanges, surrounding 



the nail, and are continued over the sue- Fig. 763. 



ceeding phalanges as a coarser plexus in f. . v..^ 



which longitudinal trunks (vv. digitales 

 dorsales propriae) can be more or less 

 distinctly perceived. At about the middle 

 of the dorsum of the proximal phalanges 

 transverse arches (arcus venosi digitales), 

 one for each digit, connect the various 

 dorsal digital veins ; each arch is concave 

 proximally, and at either end unites with 

 the extremities of the neighboring arches 

 to form four dorsal metacarpal veins 

 (vv. metacarpeae dorsales) which pass 

 upward along the lines of the intermeta- 

 carpal spaces. Just before joining with 

 its neighbors each digital arch receives 

 intercapitular veins (vv. intercapitu- 

 lares) which ascend in the web of the 

 fingers from the volar surface and assist in 

 the passage of the blood of the superficial 

 volar veins into those of the dorsal surface. 



The four dorsal metacarpal veins are 

 abundandy connected by anastomosing 

 branches which pass obliquely from one 

 vein to the other, a net-work (rete venosum 

 dorsale manus) with elongated meshes 

 being thus formed. The veins of the first 

 and fourth intermetacarpal spaces, as a 

 rule, however, retain a greater amount of 

 individuality than the other two, and have 

 consequently received special names, that 

 of the first interspace being sometimes 

 termed the vena cephalica pollicis, 

 while that of the fourth interspace is the 

 vena salvatella. The dorsal net-work 

 is drained by two veins which pass up the 

 forearm, the cephalic and basilic veins. 



The superficial veins of the volar 

 surface of the hand are small and for the 

 most part open into the dorsal veins. 

 They arise as a plexus in the balls of the 

 fingers and pass along the volar surfaces 

 of the digits as a plexus in which longitudi- 

 nal trunks (w. digitales volares propriae) 

 can be distinguished. From the plexus of each finger branches wind around the sides of 

 the digits to open into the dorsal digital veins, and at the roots of the fingers important 

 connections in a similar direction are made by the intercapitular veins (see above). 



Superficial veins of right hand and 

 forearm ; posterior surface. 



