ANATOMY IN A NUTSHELL. 95 



two heads of the Three inner dorsal interossei to join the dorsal interosseous 



arteries. 



The palmar recurrent, two or three, pass towards the wrist and join the 

 anterior carpal and anterior interosseous t<> supply the wrist-joint. 



Relations of the Radial Artery in the Forearm. 



In Front. — (1) Skin. (2) Superficial and deep fasciae, 3 Supinator 

 Longus. 



Behind. — (1) Tendon of Biceps, (2) Supinator brevis, (3) Pronator radii 

 teres, (4) Flexor sublimis digitorum, (5) Flexor longus pollicis, (6) Pronator 

 quadratus, (7) radius. 



Outp:r Side. — (1) Supinator longus, (2) Radial nerve (middle thir 



Inner Side. — (1) Pronator radii teres. (2) rdexor carpi radialis. 



LESSON XXIII. 



Ulnar artery. — The ulnar artery is a branch of the brachial about one-half 

 an inch below the bend of the elbow. It is larger than the raidal. which seems 

 to be a continuation of the brachial . It passes over the anterior annular lig- 

 ament on the radial or outer side of the pisiform bone. 



The anterior ulnar recurrent arises from the ulnar just below its origin. 

 11 passes towards the elbow upon the Brachialis anticus and under the Pro- 

 nator radii teres to the front of the internal condyle to anastomose with the an- 

 terior branch of the inferior profunda and the anastomotica magna. 



The posterior ulnar recurrent is the larger of the vessels and has its origin 

 below the anterior. It passes backward and inward upon the Flexor sublimis 

 digitorum. It passes between the two heads of Flexor carpi ulnaris, with the 

 ulnar nerve, to the back of the internal condyle to anastomose with the 

 posterior branch of the inferior profunda and the anastomotica magna. 



The common interosseous is the next in order, having its origin opposite 

 the bicipital tuberosity. It passes upward and distally to the beginning of the 

 interosseous membrane where it divides into anterior interosseous and pos- 

 terior interosseous. The lumen of this branch is the largest of the branches. 



The anterior interosseous passes to the distal extremity of the interosseous 

 membrane in company with the anterior int< - nerve, where il pass 



the back of the forearm. It has venae comites. It sends a branch with the 

 median nerve called the median artery or conn.- nervi mediani. At the wrist it 

 anastomoses with the anterior carpal artery and recurrent branches from the 

 deep palmar arch. It may help to form the superficial palmar arch. It gives 

 nutrient branches to both the radius and ulna. 



The posterior nterosseous artery passesto the back of the forearm between 

 the oblique ligamenl and inl - membrane. It passes between the 



Supinator brevis and the Extensor ossis metacarpi pollicis, then lies between 

 the two layers of muscles on posterior part of forearm as far as the wrist. It 

 lies internal to posterior interosseous nerve. It anastomoses with the carpal 

 of radial and ulnar, and anterior interosseous arteries. It gives off the posterior 

 interosseous recurrent which passes under the Anconeus to the interval be- 

 tween olecranon and external condyle, where it anastomoses with the superior 

 profunda, the anastomotica magna and posterior ulnar recurrent. 



The muscular branches vary in number and supply the adjacent muscles. 



