THE BRACHIAL ARTERY. 
supply the deltoid. 
than the subscapular. 
785 
Asarule it is an artery of large size, only shghtly smaller 
Branches.—(a) Muscular to the teres major and minor, the triceps heads, long 
ascends 
and external, and 
acromial process, where it anastomoses with 
the acromial branches of the suprascapular and 
the acromio-thoraciec arteries ; (c) A descending 
branch, which runs downwards along the external 
head of the triceps to anastomose with the 
superior profunda artery ; (7) Articular to the 
shoulder-joint; (¢) Nutrient to the head of 
the humerus; (f) Terminal, which supply a 
large portion of the deltoid, and anastomose 
with the anterior circumflex and acromio-thoracic 
arteries. 
(7) The anterior circumflex artery 
(a. circumflexa humeri anterior) is a small 
branch which is given off from the third 
part of the axillary close to, or in common 
with, the posterior circumflex. It passes 
outwards beneath the coraco-brachials and 
the two heads of the biceps, round the front 
of the surgical neck of the humerus, and 
terminates by anastomosing with the posterior 
circumflex. At the bicipital groove it gives 
a well-marked ascending bicipital branch 
which ascends along the long head of the 
biceps, supplying the sheath of the tendon, 
and giving branches to the shoulder-joint. 
It also gives muscular branches to the 
adjacent muscles, one of which descends 
along the tendon of insertion of the pectoralis 
major. 
THE BRACHIAL ARTERY. 
The brachial artery (a. brachialis) is 
the direct continuation of the axillary. It 
commences at the lower border of the teres 
major, and terminates in the ante-cubital 
fossa at the level of the neck of the radius, 
by dividing into the radial and ulnar arteries. 
The general course of the brachial artery 
is downwards and outwards, along the inner 
side of the arm. Its position may be indicated 
on the surface by a line drawn from the lower 
part of the axillary space at the junction of 
its anterior and middle thirds to the centre 
of the bend of the elbow. 
the deltoid; (6) An acromial branch, 
which to the 
Deltoid 
Pectoralis 
major 
‘\\____ Latissimus 
\ dorsi 
\— Teres major 
Triceps 
Superior 
— > protunds 
artery 
; _— Ulnar nerve 
Inferior 
~ profunda 
artery 
| Median 
nerve 
Biceps 
_____ Brachial 
artery 
Anastomotie 
artery 
Brachialis 
anticus 
Pronator 
teres 
Bicipital 
fascia 
Supinator 
longus 
Fic. 562.—THE BRACHIAL ARTERY AND ITS 
BRANCHES. 
Relations.— Posterior.—It rests successively upon the long head of the triceps, the 
musculo-spiral nerve and the superior profunda artery intervening, the internal head of 
the triceps, the insertion of the coraco-brachialis and the brachialis anticus. 
5 . 
Anterior.— 
It is overlapped ¢m front by the inner border of the biceps, is crossed at its centre by the 
median nerve, and in addition is covered by deep and superficial fascia and by skin. In 
the ante-cubital fossa a thickened portion of the deep fascia, the semilunar or bicipital 
fascia, separates it from the median basilic vein and the anterior branch of the internal 
cutaneous nerve, both of which lie in the superficial fascia. Lateral.—To the outer side 
it is in relation above with the median nerve, and below with the biceps. ‘To the cnner 
side it is in relation in the upper part of its extent with the basilic vein, the internal 
50 
