414 



Arteries of the Aitu. 



457. Arteries of the right forearm, viewed from behind. 



A. collateralis media - 



A. collateralis radialis - 

 " A. recurrens radialis. 



A. collateralis ulnaris 

 inferior 



l!ete articulare cubiti 

 Olecranon, 



N. ulnaris . 

 A. recurrens. 

 ulnaris 



M. iiexor 

 carpi ulnaris 



A. interossea 

 recurrens 



M. supinator 



A. interossea- - 

 dorsalis 



;M. extensor carpi 

 radialis longus 



M. abductor pollicis 

 longus 



Ulna 



M. extensor 

 pollicis longus 



M. extensor carpi 

 ulnaris 



.M. extensor pollicis bvevis 



Terminal branch of the 



a. interossea volaris 



A. interossea dorsalis 



Radius 

 M. extensor indicis proprius 



Rete carpi dorsale 



Ramus carpeus 

 dorsalis a. ulnaris 



Ramus carpeus dorsalis a. radialis ' 

 M. extensor carpi radialis longus 



(The lu. extonsor digitorura communis has been 



completely removed, the mm. extensores carpi, 



indicis proprius, digiti V proprius partially.) 



6. A. interossea communis (continued): 

 b) A. ititei'ossea dorsalis (0. T. posterior 

 interosseus artery), perforates the mem- 

 brana interossea a little below the chorda 

 obhqua, appears at the lower margin of 

 the origin of the m. supinator and then 

 runs almost straight distalward upon the 

 ulnar origins of the mm. abductor pollicis 

 longus, extensor polhcis longus and ex- 

 tensor indicis proprius. It is distributed 

 to the adjacent muscles and skin and 

 ends in the rete carpi dorsale. Branch : 

 bb) A. interossea recurrens (O.T. interosseus 

 recurrent or posterior interosseus re- 

 current), runs upward upon or near the 

 m. supinator (covered by the m. an- 

 conaeus), gives off branches to both 

 muscles and to the skin covering them 

 and goes to the rete articulare cubiti. 

 Rete articulare cubiti (see also Fig. 454) 

 is a wide vascular netw(jrk, situated especially 

 on the dorsal surftice of the elbow joint, in part 

 more superficially' upon the olecranon and the 

 tendon of the m. triceps, in part deeper between 

 this tendon, the humerus and the elbow joint. 

 Opening into it from above are the aa. collate- 

 rales ulnares superior et inferior, collateralis 

 media and collateralis radialis, from below large 

 branches from the posterior a. recurrens ulnaris 

 and the a. interossea recurrens and small branches 

 from the a. recurrens radialis. A little above 

 the capsule of the joint there is usually a large, 

 transverse anastomosis, which is fed especially 

 by the a. collateralis ulnaris inferior. Branches 

 go off from the network to the surroiuiding 

 bones, joints, muscles and skin. 



Rete carpi dorsale (0. T. posterior carpal 

 rete) (see also Fig. 458), lies upon the back of 

 the wrist and is an-anged in two layers: one 

 more superficial, consisting of finer vessels, upon 

 the lig. carpi dorsale and one deeper, directly 

 upon the ligaments and bones of the wrist. The 

 rete is formed by the rami carpel dorsales of 

 the a. radialis and of the a. ulnaris, as well as 

 by the terminal branches of the aa. interosseae 

 volaris et dorsalis. From the deep part of the 

 network arise 3 aa. metacarpeae dorsales (0. T. 

 dorsal interosseous arteries), which run distalward 

 upon the mm. interossei dorsales II, III and IV. 

 one upon each, each dividing at the level of the 

 heads of the ossa metacarpalia into 2 aa. digi- 

 lalcs dorsales (dorsal digital arteries) for the 

 adjacent margins of the 2"<i to the 5th finger. 

 The latter vessels are short and end in the 

 region of the first joint of the finger. A vessel 

 arises usually directly from the network for the 

 ulnar margin of the little finger. The aa. meta- 

 carpeae dorsales receive the rami perforantes of 

 the aa. metacarpeae volares. 



