The interosseous muscles have been removed, except those of the third
and fourth digits. 1, M. abductor digiti quinti; 2, 3, Mm. interossei
of third and fourth digits; 4, M. adductor pollicis; 5, M. flexor
brevis pollicis. _a_, termination of radial artery; _b_, palmar arch;
_c_, A. princeps pollicis et indicis; _d_, Aa. interosseæ; _e_,
muscular branches of the same; _f_, A. ulnaris; _g_, deep palmar
branch of ulnar nerve.]
Branches of the cœliac artery:
1. =A. hepatica= (_d_).--The hepatic artery passes cranioventrad,
pierces the descending limb of the great omentum and passes craniad to
the liver, lying, together with the portal vein and common bile-duct, in
the ventral boundary of the foramen epiploicum (foramen of Winslow) and
contained, together with the last-named vessels, in a fibrous sheath
called the capsule of Glisson. Just before entering the sheath it gives
off the =gastroduodenalis= (_g_). At its termination the hepatic artery
divides, sending branches to the lobes of the liver and a =cystic=
artery to the gall-bladder.
[Illustration: FIG. 125.--THE CŒLIAC ARTERY AND ITS BRANCHES.
_a_, abdominal aorta; _b_, A. cœliaca; _c_, A. mesenterica superior
(cut); _d_, A. hepatica (cut); _e_, A. gastrica sinistra; _f_, A.
lienalis; _g_, A. gastroduodenalis (cut from A. hepatica); _h_, A.
pylorica; _i_, A. gastroepiploica dextra; _j_, A.
pancreaticoduodenalis superior; _k_, A. pancreaticoduodenalis inferior
(cut from inferior mesenteric); _l_, A. ventriculi dorsalis. 1,
spleen; 2, stomach; 3, duodenum; 4, pancreas.]
_a._ =A. gastroduodenalis= (_g_).--This arises from the hepatic
near the pylorus and passes caudad, dividing one or two centimeters
from its origin into three branches, =A. pylorica= (_h_), =A.
pancreaticoduodenalis superior= (_j_), and =A. gastroepiploica dextra=
(_i_). The =pylorica= (_h_) (which may arise directly from the hepatic)
passes to the pylorus, thence along the lesser curvature of the stomach,
dividing into numerous branches and anastomosing with the gastrica
sinistra. The =pancreaticoduodenalis superior= (_j_) passes to the
duodenum, supplying it and the duodenal part of the pancreas and
anastomosing with the pancreaticoduodenalis inferior (_k_). The
=gastroepiploica dextra= (_i_) passes along the greater curvature of the
stomach from the pyloric end and supplies the walls of the stomach,
sending branches also to the ascending limb of the great omentum. These
branches anastomose with the terminal branches of the splenic artery.
2. =A. gastrica sinistra= (_e_).--This arises from the cœliac artery and
passes to the lesser curvature of the stomach, extending along this to
the right. It gives off many branches to the walls of the stomach, and
anastomoses with A. pylorica.
=A. ventriculi dorsalis= (_l_).--One or two small arteries which arise
either from the gastrica sinistra or the cœliac artery, and pass toward
the dorsal part of the greater curvature of the stomach near its cardiac
end.
3. =A. lienalis= (_f_).--The splenic artery is the largest of the
branches of the cœliac axis, of which it appears to be the direct
continuation. It divides into two large branches, one to the cranial
end, the other to the caudal end, of the spleen (1). From the latter a
large branch passes to the pancreas and descending limb of the great
omentum.
B. =A. mesenterica superior= (Fig. 126, _d_).--The superior mesenteric
artery is larger than the cœliac. It supplies the blood to the small
intestines and caudal portion of the pancreas and to the ascending and
transverse colon. It arises from the ventral side of the abdominal aorta
about one centimeter caudad of the cœliac axis and passes caudoventrad,
forming a curve with the convexity dextrad. It gives off the
=pancreaticoduodenalis inferior=, =colica media=, =colica dextra=,
=ileocolica=, and numerous branches to the small intestine.
1. =A. pancreaticoduodenalis inferior= (Fig. 125, _k_).--This passes to
the caudal end of the pancreas and a part of the duodenum, anastomosing
with the pancreaticoduodenalis superior.
2. =A. colica media= is a large branch to the transverse and descending
portions of the large intestine. It divides and sends branches in both
directions which anastomose with the colica dextra and with branches
from the inferior mesenteric arteries.
3. =A. colica dextra.=--A small branch which passes to the ascending and
transverse colon, anastomosing with the colica media and ileocolica. It
is sometimes absent.
4. =A. ileocolica.=--This passes to the cæcum and supplies that
structure, sending branches to the ileocolic valve and the caudal end of
the ileum, and anastomosing with the colica dextra and the intestinal
branches of the superior mesenteric.
5. The superior mesenteric now divides into about sixteen terminal
branches which pass to the small intestine. In many cases these branches
unite near the intestine, forming arches, and from these arches numerous
short branches pass to the intestine.
3. =A. adrenolumbalis= (or =lumboabdominalis=) (Fig. 126, _e_).--This
rises from the aorta, one on each side, about two centimeters caudad of
the superior mesenteric. Each passes laterad onto the dorsal body wall,
supplying the muscles of this region. A large branch passes caudad along
the surface of the muscles dorsad of the kidney and anastomoses with the
iliolumbar artery. From the adrenolumbalis rises usually:
=A. phrenica= (_f_).--The phrenic artery rises either from the cœliac
(_c_) or the adrenolumbalis (_e_) and passes to the diaphragm, near its
dorsal border. In the diaphragm it passes ventrad, lying at the medial
margin of the costal portion of the diaphragm, as far as its sternal
portion, where it unites with the artery of the opposite side. The two
thus form an arch, from which radiating arteries pass off to supply the
diaphragm.
4. =A. renalis= (_g_).--The two renal arteries arise from the sides of
the aorta, usually at about the same point, so that the left passes
caudolaterad and the right craniolaterad (owing to the position of the
kidneys). The artery usually divides just before entering the kidney
(2). It passes dorsad of the vein (_t_). The renal artery sometimes
sends a branch to the suprarenal body (1). It also occasionally gives
origin to the spermatic artery (_h_).
[Illustration: FIG. 126.--ABDOMINAL BLOOD-VESSELS, VENTRAL VIEW.
_a_, vena cava inferior; _b_, abdominal aorta; _c_, A. cœliaca (cut);
_d_, A. mesenterica superior (cut); _e_, A. adrenolumbalis; _f_, A.
phrenica; _g_, A. renalis; _h_, A. spermatica interna; _i_, A.
mesenterica inferior (cut); _j_, A. iliolumbalis; _k_, A. iliaca
externa; _l_, A. hypogastrica; _m_, beginning of A. femoralis; _n_,
A. umbilicalis; _o_, A. and V. sacralis media (_o_, the artery; _o′_,
the vein); _p_, A. glutea superior; _q_, A. glutea inferior; _r_, A.
and V. hemorrhoidalis media; _s_, V. adrenolumbalis; _t_, V. renalis;
_u_, V. spermatica interna; _v_, V. iliolumbalis; _w_, V. iliaca
communis; _x_, V. femoralis; _y_, V. and A. profunda femoris; _z_, V.
hypogastrica. 1, suprarenal body; 2, kidney; 3, ureter; 4, outline
(broken) of rectum.]
5. =A. spermatica interna= (_h_).--This rises from the aorta on each
side at about the level of the caudal ends of the kidneys, and passes
laterad (or it may arise from the renal). In male specimens the artery
turns caudad, along with the corresponding vein (_u_), and passes to the
inguinal canal. Thence it passes along with the vas deferens and the
vein (forming all together the spermatic cord) to the testes and the
other structures in the scrotum.
In females (Fig. 112, 2, page 265) the artery is larger and passes more
nearly directly laterad, being much convoluted. It passes to the ovary,
being now called the =ovarian artery=. It sends branches into the ovary
(_c_) and to the cranial end of the uterus (_f_); the latter
anastomosing with branches of the uterine artery (3).
6. =A. mesenterica inferior= (Fig. 126, _i_).--The inferior mesenteric
artery has its origin from the aorta at about the level of the last
lumbar vertebra. It passes toward the large intestine, and near it
divides into two branches, the =colica sinistra=, which passes craniad
along the descending colon, anastomosing with the colica media, and the
=superior hemorrhoidal=, which passes caudad along the descending colon
and rectum and anastomoses with the middle hemorrhoidal (page 308).
7. =A. iliolumbalis= (Fig. 126, _j_).--The iliolumbar arteries arise
from the aorta about two centimeters caudad of the inferior mesenteric
and pass laterad over the ventral surface of the psoas minor and
iliopsoas muscles. Each divides into two main branches, one passing
caudad and the other craniad; these supply the muscles of this region.
The cranial branch anastomoses with branches of the adrenolumbalis
(_e_). The caudal branch sends an artery through the abdominal wall to
appear at the cranial edge of the thigh; it passes onto the lateral
surface of M. sartorius and extends here some distance distad.
8. =A. lumbalis.=--There are usually seven pairs of lumbar arteries,
passing almost directly dorsad from the dorsal surface of the aorta; the
first pair arising just craniad of the diaphragm, the last at the same
level as the origin of the external iliac. The two arteries of a pair
usually arise from the aorta one behind the other, or they may arise by
a common trunk. They correspond to the intercostal arteries. They pass
between the centra of the vertebræ and the muscles of the dorsal region,
and send one main branch laterad, the other dorsad; both supply the
dorsal muscles. From the dorsal branch small arteries pass into the
vertebral canal to join the anterior spinal artery.
9. =A. iliaca externa= (Fig. 126, _k_).--The external iliac artery
passes obliquely caudad from the aorta, lying ventrad of the common
iliac vein and against the medial surface of the psoas minor muscle. It
passes onto the ventral surface of this and the iliopsoas and at the
same time reaches the tendon of the abdominal muscles; through a small
opening in this tendon lying ventrocaudad of that for the iliopsoas, it
leaves the abdominal cavity. On its emergence from the abdominal cavity
onto the medial surface of the thigh it receives the name =A. femoralis=
(_m_). The branches of the external iliac artery are described below
(page 309).
10. =A. hypogastrica= (or iliaca interna) (Fig. 126, _l_).--The
hypogastric or internal iliac arteries are given off from the aorta
usually within a centimeter caudad of the external iliac. Each passes
caudolaterad, lying on the medial side of the common iliac vein, and
divides into branches which supply the structures within the pelvis and
the muscles about the pelvic wall. There is much variation in the origin
and relations of the branches of this artery. The following seems to be
a very common arrangement: A very short distance from the origin the
=umbilical= artery (_n_) is given off. The hypogastric artery then
extends two or three centimeters and gives off =A. glutea superior=
(_p_), which passes at once to the pelvic wall. A little farther caudad
the hypogastric divides into the =middle hemorrhoidal= (_r_), to the
rectum, and the =glutea inferior= (_q_), which passes out of the
pelvis.
Branches of the hypogastric artery:
_a._ =A. umbilicalis= (Fig. 126, _n_).--This small artery arises from
the hypogastric about one centimeter from the beginning of the latter,
and passes ventrad to the bladder. Here it divides into two
branches--the =superior vesical= to the sides of the bladder, the
=inferior vesical= to the neck of the bladder and the urethra.
_b._ =A. glutea superior= (Fig. 126, _p_).--This passes dorsolaterad
from the hypogastric and reaches the pelvic wall against the medial
surface of the ilium. Here it divides into two branches. One passes
between the iliopsoas muscle and the ventral border of the ilium to the
medial surface of the gluteus maximus; it gives branches to the gluteus
muscles, the pyriformis, and the rectus femoris. The other branch passes
dorsad of the ilium, sending a branch to the medial surface of the
gluteus medius, and a small branch which joins the lateral sacral artery
and enters thus the sacral canal.
_c._ =A. hemorrhoidalis media= (Fig. 126, _r_).--The middle hemorrhoidal
passes ventrad from the hypogastric, onto the lateral surface of the
rectum. It passes caudad near the ventral side of the rectum as far as
the anus. A short distance from the origin it gives off a branch which
passes almost directly ventrad toward the beginning of the urethra. In
the male this branch is small, sending twigs to the urethra and the
prostate. In the female it is much larger, forming =A. uterina= (Fig.
112, 3, page 265). The uterine artery turns craniad onto the uterus,
which it supplies, passing to the cranial end of the uterine cornu and
anastomosing with the ovarian artery.
The middle hemorrhoidal gives off in the female branches to the vagina
(Fig. 112, _m_) and neck of the bladder (_k_), and a large branch to the
urogenital sinus (_n_); it then supplies the anal glands and other
structures about the anus, and anastomoses with the terminal branches of
the hemorrhoidalis superior. In the male branchlets are given to the
urethra, to the bulbourethral (or Cowper’s) gland, and to the penis. The
=A. dorsalis penis= is a small branch which passes along the median
dorsal groove of the penis to the glans. The middle hemorrhoidal then
supplies the structures about the anus and anastomoses with the superior
hemorrhoidal, as in the female.
_d._ =A. glutea inferior= (Fig. 126, _q_).--This is the terminal portion
of the hypogastric. It passes along with the great sciatic nerve to the
great sciatic notch, and reaches the medial surface of M. pyriformis. It
divides into branches which supply the gluteus and pyriformis muscles,
while a small branch accompanies the great sciatic nerve. A small branch
also passes onto the lateral surface of the tail, extending caudad along
its side.
11. =A. sacralis media= (Fig. 126, _o_).--This is the continuation of
the aorta into the sacral and caudal regions. It extends to near the end
of the tail, lying in the ventral middle line against the sacral and
caudal vertebræ. In the caudal region it passes through the hæmal
arches, covered by the chevron bones. Between the vertebræ it gives off
side branches comparable to the intercostal and lumbar arteries of the
aorta.
Branches of the sacralis media:
_a._ =A. sacralis lateralis.=--Behind the first sacral vertebra a large
branch, the lateral sacral, is given off on each side. This enters the
first anterior sacral foramen, gives a branch to the structures in the
sacral canal, and sends a dorsal branch out through the posterior sacral
foramen to the muscles on the dorsal side of the sacrum.
Similar but smaller branches are given off between the succeeding
vertebræ, sacral and caudal.
_The External Iliac and its Branches._--The origin of the external iliac
(Fig. 126, _k_) is described above (page 307). It gives off the
following branches:
1. =A. profunda femoris= (Fig. 126, _y_).--This is given off just
before the external iliac leaves the abdominal cavity. It passes caudad,
and about one centimeter from its origin it gives off three branches,
sometimes all separately, sometimes two in common. One of these passes
mediad in the lateral ligament of the bladder and ramifies on the
lateral surface of that organ. A second passes through the abdominal
wall and into the fat on the medial surface of the thigh; it sends a
branch caudad toward the external genital organs, while its main trunk
passes distad in the subcutaneous fat almost to the knee. From one of
these two a small branchlet passes in the male to the spermatic cord and
accompanies this to the testis; it represents thus the =external
spermatic artery=. The third branch, =A. epigastrica inferior=, passes
directly to the ventral surface of the rectus abdominis muscle, on which
it passes craniad, sending branches to the muscles of the abdominal
walls. It anastomoses with terminal branches of the internal mammary
artery.
The profunda femoris itself passes between the iliopsoas and the
pectineus muscles, then to the medial surface of the adductor femoris.
It divides into branches which supply the pectineus, adductor longus,
adductor femoris, caudofemoralis, quadratus femoris, semimembranosus,
and semitendinosus.
[Illustration: FIG. 127.--SUPERFICIAL ARTERIES, VEINS, AND NERVES ON
THE MEDIAL SIDE OF THE LEG.
_a_, A. and V. femoralis; _b_, N. femoralis; _c_, A. profunda femoris;
_d_, A. and V. circumflexa femoris lateralis; _e_, ramus muscularis;
_f_, A. saphena and V. saphena magna; _g_, N. saphenus; _h_, A. and V.
articularis genu suprema; _i_, N. tibialis; _j_, plantar branch of A.
saphena; _k_, dorsal branch of A. saphena. 1, M. sartorius; 2, M.
tensor fasciæ latæ; 3, M. rectus femoris; 4, M. iliopsoas; 5, M.
pectineus; 6, M. adductor longus; 7, M. adductor femoris; 8, M.
semimembranosus; 9, M. gracilis; 10, M. semitendinosus; 11, medial
head of M. gastrocnemius; 12, M. plantaris; 13, M. flexor longus
digitorum; 14, M. tibialis anterior; 15, tibia.]
2. =A. femoralis= (Fig. 127).--This is the continuation of the external
iliac onto the medial surface of the thigh. The artery lies in a
triangular depression between the borders of the sartorius (1) and
gracilis (9) muscles. The floor of the depression is formed by the
adductor longus (6), pectineus (5), vastus internus, and rectus femoris
(3) muscles. This triangular depression is known as the =iliopectineal=
fossa, or Scarpa’s triangle; it contains also the femoral vein (_a_) and
saphenous nerve (_g_), which pass along with the artery. The artery
extends distad, and at about the middle of the length of the thigh it
passes, along with the vein and nerve, into a groove between the vastus
medialis and the adductor femoris. This groove is converted into a canal
by the overlying aponeurosis; it is known as =Hunter’s canal= or the
=canalis adductorius=. At the distal end of the adductor femoris the
femoral artery ceases to be superficial and passes between the vastus
medialis and the semimembranosus to the popliteal space; it now receives
the name =A. poplitea=.
Branches of the femoral artery:
_a._ =A. circumflexa femoris lateralis= (Fig. 127, _d_).--The lateral
circumflex arises from the femoral about one centimeter from its
emergence from the abdominal cavity. It passes craniad and laterad and
divides into two main portions. One part passes between the rectus
femoris and vastus medialis, gives branches to these muscles, and sends
an ascending branch to the structures about the hip-joint, and a
descending branch into the vastus medialis muscle. The remainder of the
lateral circumflex passes along the inner (lateral) surface of the
sartorius (1) to the cranial border of the leg, giving branches to the
sartorius (1) and tensor fasciæ latæ (2).
_b._ A large =muscular= branch (_e_) passes caudad (or ventrad) and
distad across the distal end of the adductor femoris (7) and between the
gracilis (9) and semimembranosus, supplying these muscles. Other small
muscular branches may be given off from both sides of the femoral.
_c._ =A. articularis genu suprema= (_h_).--The superior articular artery
arises from the femoral, either in common with the saphenous artery or
separately, a little proximad of the point where the femoral ceases to
be superficial. It passes toward the knee, between the vastus medialis
and semimembranosus, and covered by the sartorius (1), and ramifies over
the medial surface of the knee-joint and in the structures just proximad
of the joint.
_d._ =A. saphena= (_f_).--The saphenous artery frequently takes origin
in common with the superior articular (_h_), but may arise separately at
about the same level. It passes distad across the gracilis (9),
accompanied by the saphenous nerve (_g_) and vein, sends several
branches dorsad (toward the knee), and at about the middle of the lower
leg it divides into two main branches, a =dorsal= branch (_k_), passing
to the dorsum of the foot, and a =plantar= branch (_j_), to the sole of
the foot. The dorsal branch is accompanied by the main saphenous nerve
(_g_) and vein. It sends one or two branches to the medial side of the
ankle-joint, passes then onto the dorsum of the foot, and divides into
four main branches. The medial one passes along the medial side of the
medial digit; the other three pass to the intervals between the digits.
Each divides into two branches which supply the contiguous sides of the
two digits between which the interval lies. The dorsal branch thus
supplies arteries to the sides of all the digits except to the lateral
side of the lateral digit. This is supplied by A. suralis.
The plantar branch (_j_) is larger than the dorsal. It passes distad on
the medial surface of the flexor longus hallucis, accompanied by the
tibial nerve, and across the space between the tendon of Achilles and
the flexor. It gives superficial and deep branches to the structures
about the ankle-joint, and sends inward a branch from the lateral side
(Fig. 128, _d_) which joins the termination of A. tibialis anterior to
form the plantar arch. It then passes distad along the plantar surface
of the foot, nearer its medial border. Beneath the pad in the sole of
the foot it divides into three branches which supply the interosseous
spaces between the three digits.
_e._ =A. poplitea.=--The main trunk of the femoral artery passes between
the vastus medialis and the semimembranosus and then through the distal
portion of the adductor femoris to reach the popliteal space. This is
the space ventrad (or caudad) of the knee, between the biceps femoris on
one side and the semimembranosus on the other. Here the artery receives
the name =A. poplitea=, or popliteal artery. The popliteal artery gives
off a number of large branches as it passes through the popliteal space,
passes between the condyles of the femur and underneath the popliteal
muscle, and finally turns dorsolaterad between the tibia and fibula,
just distad of the head of the fibula. It now receives the name =A.
tibialis anterior= and passes distad along the dorsal (anterior) border
of the fibula.
Branches of the popliteal artery:
1. =A. suralis.=--This is a large branch which passes distad from the
caudal side of the popliteal artery. It sends branches to the biceps and
to the fat in the popliteal space, and passes onto the ventral border of
the lateral head of the gastrocnemius. It sends branches to both heads
of the gastrocnemius and to the popliteus, passes distad onto the
lateral surface of the tendon of Achilles, and may be traced to the
proximal portion of the dorsolateral side of the foot, where it sends
many branches to the integument about the ankle-joint. It then passes
along the lateral side of the foot and supplies the artery on the
lateral side of the fifth digit.
2. =Aa. genu posteriores.=--Several small arteries which pass to the
knee-joint.
3. =Rami musculares.=--Numerous small branches to the muscles about the
popliteal space.
4. =A. tibialis posterior.=--This is the largest branch of the popliteal
artery, which it leaves just before the latter passes beneath the
popliteal muscle. The tibialis posterior passes at first mediad, then
turns distad, passes across the popliteus muscle onto the surface of the
flexor longus hallucis, and ramifies in the substance of this muscle and
its tendon. It gives branches also to the gastrocnemius and soleus. (It
does not pass into the foot as does the corresponding artery in man.)
5. =A. tibialis anterior.=--The anterior tibial artery is the
continuation of the popliteal after its passage through the interosseous
membrane between tibia and fibula to the dorsal side of the lower leg.
Here it passes distad, lying against the interosseous membrane, between
the extensor longus digitorum and the tibialis anterior muscle, or
partly imbedded in the substance of the latter. It passes, lying beneath
the tendons of these muscles, through the transverse ligament proximad
of the malleoli, thus reaching the dorsum of the foot. It extends distad
across the tarsus to the space between the second and third metatarsals,
and through this space to the plantar side of the foot (Fig. 128). Here
it receives one or two small branches (_a_ and _d_) from the plantar
branch of A. saphena (forming with them the =plantar arch= (_c_)), and
passing distad and slightly laterad, divides into three main portions
(_e_). These (=Aa. digitales plantares=) pass to the three intervals
between the digits. The medial one passes along the lateral side of the
second digit; the next divides, sending a branch to the lateral side of
the third digit and the medial side of the fourth; the lateral one
passes along the medial border of the fifth digit. The Aa. digitales
plantares send numerous branches to the interosseous muscles.
[Illustration: FIG. 128.--DEEP ARTERIES ON THE PLANTAR SURFACE OF THE
FOOT.
_a_, medial twig from plantar branch of A. saphena; _b_, A. tibialis
anterior (or plantaris profunda); _c_, plantar arch; _d_, lateral twig
from plantar branch of A. saphena; _e_, terminal branches from A.
tibialis anterior.]
Branches of the tibialis anterior:
_a._ =A. tibialis recurrens.=--Immediately after passing through the
interosseous membrane the anterior tibial sends a small artery proximad
to the knee-joint.
_b._ =Rami musculares.=--Numerous short branches throughout the course
of the artery, to the muscles about it.
_c._ =Ramus superficialis.=--A larger branch leaves the lateral surface
of the artery about one-third the distance from the knee to the ankle
and passes along with the superficial peroneal nerve, at first beneath
M. peroneus longus, then superficially. It passes onto the dorsal
surface of the foot and becomes connected with terminal branches of =A.
saphena=.
_d._ =A. tarsea medialis.=--This arises from the tibialis anterior just
distad of the transverse ligament through which it passes at the ankle,
passes over the medial surface of the astragalus, and is distributed to
the ligaments about the ankle-joint. It anastomoses with the plantar
branch of A. saphena.
_e._ =A. metatarsea.=--The metatarsal artery passes laterad from the
tibialis anterior at the distal boundary of the tarsus, on the dorsal
surface of the foot. It sends branches distad in the intervals between
the third and fourth and the fourth and fifth metatarsals.
The distal branches (Fig. 128) of the tibialis anterior have been
described in the general description of the artery.