Download Vessels of Lower Abdomen, Thigh, and Leg

Vessels of Lower Abdomen, Thigh, and Leg
Key reference you must locate: Descending Abdominal Aorta
Follow the Descending Abdominal Aorta downward (inferiorly) to where it
splits forming an upside-down “Y”. Each arm of the “Y” is the Common Iliac
Artery. However, not all of each arm is the Common Iliac. About 1/3 away from
the split, a vessel comes off and goes inferior. This vessel is the Internal Iliac
Artery. The Internal Iliac Artery has 4 major branches going in various directions.
The branch that feeds the medial surface of the thigh is the Superior Gluteal
Artery and a second branch, the Inferior Gluteal Artery, services the gluteal
muscles and hip joint. We will not follow the other two branches of the Internal Iliac
Artery. Also, right at the split, a dorsally emerging Median Sacral Artery services
the sacrum and caudal regions of the vertebral column. Once the internal iliac
artery branches off the common iliac artery, the common iliac becomes the
External iliac artery. Follow the external iliac artery under the Inguinal Ligament
(white band of tissue) and the external iliac becomes the Femoral artery. (You can
see the femoral artery, vein, and nerve in the Femoral Triangle area of the groin.)
A few inches down the groin, the Deep Femoral Artery branches from the lateral
side of the femoral artery where it divides multiple times. One branch, the
Circumflex femoral artery, encircles the head of the femur, and continuing
inferiorly and laterally, the Descending Branch of the Lateral Circumflex Artery,
services the femur shaft, hip joint, and hamstring muscles. The femoral artery
disappears into several of the adductor muscles on the medial side of the leg and
reappears as the Popliteal artery near the back of the knee in the depression
called the Popliteal Fossa. The popliteal artery ends when it divides into Anterior
and Posterior Tibial Arteries at the inferior end of the fossa. On the femur end of
the popliteal artery, Superior Lateral and Medial Genicular Arteries arise while
on the tibial end of the popliteal artery Inferior Lateral and Medial Genicular
Arteries arise. The anterior tibial artery parallels the anterior surface of the tibia
bone servicing the extensor foot muscles and then becoming smaller arteries in the
foot. The posterior tibial artery passes along the posterior surface of the tibia and
services the flexor foot muscles and ends as other small arteries servicing the foot
after it passes behind the medial malleolus of the tibia.
VEINS
Start on the dorsal surface of the foot at the Dorsal Venous Arch. From the
lateral edge of the arch arises the Small Saphenous Vein proceeding up the side
of the calf muscles and joining the Popliteal Vein (Right next to the Popliteal
Artery). Using the Small Saphenous Vein is the easiest way to distinguish between
the Popliteal Vein and Artery (i.e the Popliteal Vein is NOT going to join the artery!).
From the medial side of the Dorsal Venous Arch arises the Great Saphenous
Vein. This very long vein, pretty much the entire length of one’s leg, joins the
129
7/21/2009
Femoral Vein right before it disappears below the inguinal ligament. The femoral
vein is also right next to the femoral artery in the upper thigh/groin region of the leg
and with the Femoral Nerve forms the Femoral Triangle.
Vessels of Upper Thoracic Cavity, Shoulder, and Arm
Key reference you must locate: Left or Right Subclavian Arteries.
Coming off of either subclavian artery from medial to lateral are: Internal
Thoracic Artery (Practical I) descending inside the sternum and ribs, Vertebral
Artery (Practical I) ascending into the transverse foramen of the cervical vertebrae,
and the Thyrocervical (YOU ARE NOT RESPONSIBLE FOR THIS VESSEL). After
the thyrocervical and the superior border of the first rib, the subclavians become the
Axillary Arteries, now in the axilla or armpit. Several other branches arise, but the
Circumflex Humeral Artery (There are anterior and posterior branches of this
vessel.) comes off last and surrounds the humerus head. After the Circumflex
Humeral branches, the axillary becomes the Brachial Artery descending down the
upper arm next to the humerus. At about ¼ of its length, two branches exit: laterally
is formed the Radial Collateral Artery and, once passing the distal humerus, it
becomes the Radial Recurrent Artery joining the Radial Artery; and medially is
formed the Ulnar Collateral Artery that also passes the distal humerus to become
the Ulnar Recurrent Artery; this obviously joins the Ulnar Artery. Both the Radial
and Ulnar Arteries break into the Superficial (and Deep) Arterial Palmar Arch in
the palm of the hand. The Brachial Artery, after the distal humerus, divides into the
Radial and Ulnar Arteries.
VEINS
Starting with the Superficial Venous Palmar Arch (Veins on the palm of
hand) and the Dorsal Venous Network (Back of, or dorsal surface of the hand), 4
major veins form. The Radial and Ulnar Veins run parallel to the Radial and Ulnar
Arteries along their respective bones. These veins actually arise from deep
(beneath the superficals) palmar veins (NOT ON YOUR PRACTICAL!). The Basilic
and Cephalic Veins arise from the Dorsal Venous Network. The Basilic comes
from the medial side and proceeds all the way up the arm where it joins the upper
Brachial Vein right before the Brachial Vein becomes the Axillary Vein. The
Cephalic Vein goes up the lateral surface of the arm and joins the Axillary Vein.
Right in the Cubital Fossa, the Median Cubital Vein runs obliquely joining the
Cephalic to the Basilic Vein. The Median Cubital Vein is usually where blood is
removed for testing/analysis. The Median Antebrachial Vein arises from the veins
in the Palmar Arch and will anastomose with the Basilic Vein just before the elbow.
The Axillary vein becomes the Subclavian Vein (P-I)---àBrachiocephalic Vein
(Practical I)---àSuperior Vena Cava (Practical I).
130
7/21/2009
Vessels of Abdominal Cavity
Most of the veins of the abdominal cavity run parallel to the arteries. Only
the exceptions will be noted. Once the Descending Thoracic Aorta (Practical I)
penetrates the diaphragm it becomes the Descending Abdominal Aorta. From
here many branches (some we skip) exit and go to specific organs or regions of the
abdomen. The first major branch is the Celiac Trunk (Artery). At least 3 vessels
originate from this trunk: the Left Gastric Artery that services the left side of
stomach along greater curvature, the Common Hepatic Artery that goes to the
Liver, and the Splenic Artery that goes to the Big Toe (Just kidding! Take a wild
guess where it goes?). There are some minor variations as to the order vessels
come off the Descending Abdominal Aorta, but the really important thing to
remember is that the vessel is often named for its destination. The Superior
Mesenteric Artery comes off anteriorly about an inch past the Celiac Trunk and
services the small intestine, pancreas, and most of the large intestine. Exiting
laterally almost in the same area as the Superior Mesenteric are the Renal Arteries
servicing the kidneys. Sometimes the Adrenal/Suprarenal Arteries come directly
off the Descending Abdominal Aorta and other times they come off the renal
arteries. It does not really matter where they emerge; it really matters where they
terminate! Just below the Renal Arteries exit point is usually where the Gonadal
Arteries arise. If the specimen is a female, these are called Ovarian Arteries, and
if a male, they are called Spermatic Arteries. Right where the lumbar vertebrae
begin will emerge posteriorly Lumbar Arteries. Just before the end of the
Descending Abdominal Aorta, the Inferior Mesenteric Artery emerges anteriorly
and services the lower large intestine (sigmoid colon and rectum).
The
Descending Abdominal Aorta now forks and becomes the Common Iliac Arteries.
Between this fork and running inferiorly is the Median Sacral Artery.
VEINS
Only those veins that do not parallel their respective arteries are described.
The Inferior Mesenteric Vein arises from the lower portion of the large intestine
and proceeds superiorly. The Superior Mesenteric Vein collects blood from the
stomach, small intestine, and most of large intestine returning this oxygen poor, but
nutrient-rich, blood to the Hepatic Portal Vein, also formed by the Inferior
Mesenteric and Splenic Veins. The Hepatic Portal Vein penetrates the liver right
next to the Common Hepatic Artery. The liver removes glucose, amino acids, fats,
vitamins, etc and blood emerges on the superior surface in the Hepatic Veins.
These Hepatic Veins join the Inferior Vena Cava.
131
7/21/2009