THE ARTERIES. 297 
the brachial proximad of the supracondyloid foramen, either 
separately or in common with the muscular branches, and 
passes into the nutrient foramen at the junction of the middle 
and distal thirds of the shaft of the humerus, supplying the 
bone. 
d. A. collateralis ulnaris (superior) (or A. anastomotica 
magna) (z).—This leaves the brachial artery just proximad of 
the supracondyloid foramen and passes to the convexity of the 
elbow, supplying the structures about the olecranon. 
e. A. collateralis radialis superior (Fig. 130).—This rises 
from the axillary artery just proximad of the supracondyloid 
foramen (Fig. 122, x), in company with the vena mediana cubiti 
(y), passes across the surface of the biceps (4), beneath the 
pectoantibrachialis, into the concavity of the elbow. Here it 
gives branches to the pectoantibrachialis, clavobrachialis, and 
extensor muscles of the forearm. It then passes onto the ven- 
troradial border of the forearm (Fig. 130) and runs along this 
border, ¢n company with the vena cephalica (Fig. 130, c) and 
the superficial radial nerve (g), to the wrist, sending off 
branches to the integument. At the wrist it turns onto the 
dorsum of the hand, passing in a gentle curve to the ulnar side 
and distad, and giving off a branch for the space between each 
pair of metacarpal bones. These branches (Fig. 130, ¢) 
(Aa. digitales dorsales) pass distad and anastomose with 
branches coming from the palm. 
fj. A. tradialis (Fig. 123).—Distad of the convexity of the 
elbow the brachial artery takes the name radial artery. It 
passes from the supracondyloid foramen on the medial side of 
the biceps tendon (1) and beneath the pronator teres muscle 
(5), giving off small branches, as far as the middle of the fore- 
arm, where it gives off the ulnar artery (2). It then passes 
from beneath the pronator teres (5) and lies on the surface of 
the fifth part of the flexor profundus (8 ), covered only by the 
fascia and integument. Near the wrist it sends off a branch 
(m) toward the ulnar side of the arm, which passes into the 
palm on the surface of the tendon of the flexor profundus, 
giving twigs to the digits and to the pad in the palm. A 
branch from this may join the ulnar, and the common trunk 
