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UNIT 4
Maintenance of the Body
19
Table 19.6
Arteries of the Upper Limbs and Thorax
Te upper limbs are supplied entirely by arteries arising from
the
subclavian arteries
(Figure 19.23a)
. AFer giving off
branches to the neck, each subclavian artery courses laterally
between the clavicle and first rib to enter the axilla, where its
name changes to axillary artery. Te thorax wall is supplied
by an array of vessels that arise either directly from the tho-
racic aorta or from branches of the subclavian arteries. Most
visceral organs of the thorax receive their functional blood
supply from small branches issuing from the thoracic aorta.
Because these vessels are so small and tend to vary in number
(except for the bronchial arteries), ±igures 19.23a and b do not
illustrate them, but several are listed at the end of this table.
Description and Distribution
Arteries of the Upper Limb
Axillary artery.
As it runs through the axilla accompa-
nied by cords of the brachial plexus, each axillary artery
gives off branches to the axilla, chest wall, and shoulder
girdle. ²hese branches include the
thoracoacromial
artery
(tho
0
rah-ko-ah-kro
9
me-al), which supplies the
deltoid muscle and pectoral region; the
lateral thoracic
artery
, which serves the lateral chest wall and breast; the
subscapular artery
to the scapula, dorsal thorax wall,
and part of the latissimus dorsi muscle; and the
anterior
and
posterior circumflex humeral arteries
, which wrap
around the humeral neck and help supply the shoul-
der joint and the deltoid muscle. As the axillary artery
emerges from the axilla, it becomes the brachial artery.
Brachial artery.
Te brachial artery runs down the me-
dial aspect of the humerus and supplies the anterior flexor
muscles of the arm. One major branch, the
deep artery of
the arm
, serves the posterior triceps brachii muscle. As it
nears the elbow, the brachial artery gives off several small
branches that contribute to an anastomosis serving the
elbow joint and connecting it to the arteries of the fore-
arm. As the brachial artery crosses the anterior midline
aspect of the elbow, it provides an easily palpated pulse
point (brachial pulse) (see ±igure 19.12). Immediately be-
yond the elbow, the brachial artery splits to form the radial
and ulnar arteries, which more or less follow the course of
similarly named bones down the anterior forearm.
Radial artery.
Te radial artery runs from the median
line of the cubital fossa to the styloid process of the ra-
dius. It supplies the lateral muscles of the forearm, the
wrist, and the thumb and index finger. At the root of the
thumb, the radial artery provides a convenient site for
taking the radial pulse.
Ulnar artery.
Te ulnar artery supplies the medial as-
pect of the forearm, fingers 3–5, and the medial aspect of
the index finger. Proximally, the ulnar artery gives off a
short branch, the
common interosseous artery
(in
0
ter-
os
9
e-us), which runs between the radius and ulna to
serve the deep flexors and extensors of the forearm.
Palmar arches.
In the palm, branches of the radial and ul-
nar arteries anastomose to form the
superficial
and
deep
palmar arches
. Te
metacarpal arteries
and
digital arter-
ies
that supply the fingers arise from these palmar arches.
Internal
thoracic
artery
Lateral
thoracic
artery
Anterior
intercostal
arteries
Superficial palmar arch
Metacarpal arteries
Digital arteries
Ulnar artery
Common
interosseus artery
Radial
artery
Deep
palmar
arch
Anastomosis
Subscapular
artery
Thoracic
aorta
Posterior
intercostal
arteries
Costocervical
trunk
Aortic arch
Brachiocephalic
trunk
L. subclavian
artery
L. vertebral artery
L. common carotid
artery
(a) Schematic flowchart
R. common
carotid
artery
R. vertebral artery
Thyrocervical trunk
Suprascapular artery
R. subclavian artery
Axillary artery
Thoracoacromial
artery
Thoracoacromial
artery
(pectoral
branch)
Anterior
and posterior
circumflex
humeral
arteries
Brachial
artery
Deep
artery
of arm
Figure 19.23
Arteries of the right upper limb and thorax.
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