THE POSTERIOR RADIAL ARTERY 



561 



2. Muscular branches to the flexors of the carpus and digit. The largest of 

 these arise at the proximal third of the forearm. 



3. The common interosseous artery (A. interossea communis) is a vessel of 



Artery of rete carpi volar e 



Oblique ligament 



Internal lateral lig. 

 First carpal bone 



Deep volar metacarpal arteries 

 Int. metacarpal bone 



Radius 



Accessorio-radial lig. 

 Accessorio-ulnar lig. 



t^li — Exlcrnnl lateral lig. 

 /'its ^ Check ligament 



ligai 

 A ccessorio-metacarpal lig. 



Deep volar arch 

 Suspensory ligament 

 Ext. metacarpal bone 



Fig. 444. — Dkep Dissection of Richt C.\rits of Horse, Pcsterior View. 

 1, Radial carpal bone; 2, accessory carpal bone; S, second carpal bone. (After Schmaltz, Atlas d. Anat. d. Pferdes.) 



considerable size which arises at the level of the interosseous space, through which 

 it passes. Before entering the space it gives off a small branch, the volar interos- 

 seous (A. interossea volaris), which descends to the radial head of the perforans. 

 In the space it supplies the nutrient arteries of the radius and ulna. Emerging 



Cutaneous branch of niusculo- 



cutaneous nerve 



Tendon of extensor carpi obliquus 



Lateral ligament 



Tendon of flex, carpi internus 



Int. metacarpal vein. 



Int. volar or small met. artery 



Common dig. or large met. artery 



Posterior annular ligament 



Internal metacarpal nerve 



External metacarpal vein 



External metacarpal nerve 



External volar met. artery 



Fig. 445. — Cross-section op Right Carpus of Horse. 

 The soft structures are cut at the level of the radio-carpal articulation, exposing the proximal row of carpal 

 bones. Cr, Radial carpal bone; Ci, intermediate carpal bone; Cu, ulnar carpal bone; Ca, acce.s.sorv carpal bone. 

 (After Schmaltz, Atlas d. Anat. d. Pferdes.) 



Tendon of extensor carpi radialis 

 Tendon of anterior dig. extensor 

 Skin 



Lateral ligament 



Tendon of lateral dig. extensor 



Tendon of deep dig. flexor 

 Tendon of superficial dig. flexor 

 Long tendon of flex, carpi externum 

 Superficial branch of ulnar nerve. 



from the space it gives off branches to the flexor carpi externus, a small recurrent 

 branch (A. interossea recurrens) which passes upward on the outer surface of the 

 ulna and anastomoses with the deep brachial and ulnar arteries, and is continued 

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