The inferior phrenic arteries are two small vessels which supply the
diaphragm
Diaphragm may refer to:
Anatomy
* Thoracic diaphragm, a thin sheet of muscle between the thorax and the abdomen
* Pelvic diaphragm or pelvic floor, a pelvic structure
* Urogenital diaphragm or triangular ligament, a pelvic structure
Other
* Diap ...
.
They present much variety in their origin.
Structure
Origin
The inferior phrenic arteries usually arise between
T12 and
L2 vertebrae
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic i ...
.
They may arise separately from the front of the
aorta
The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes ...
, immediately above the
celiac artery
The celiac () artery (also spelled ''coeliac''), also known as the celiac trunk or truncus coeliacus, is the first major branch of the abdominal aorta. It is about 1.25 cm in length. Branching from the aorta at thoracic vertebra 12 (T12) in ...
, or by a common trunk, which may spring either from the aorta or from the celiac artery.
Sometimes one is derived from the aorta, and the other from one of the
renal arteries
The renal arteries are paired arteries that supply the kidneys with blood. Each is directed across the crus of the diaphragm, so as to form nearly a right angle.
The renal arteries carry a large portion of total blood flow to the kidneys. Up to a ...
; they rarely arise as separate vessels from the aorta.
Branches
They diverge from one another across the
crura of the diaphragm
The crus of diaphragm (pl. crura), refers to one of two tendon, tendinous structures that extends below the thoracic diaphragm, diaphragm to the vertebral column. There is a right crus and a left crus, which together form a tether for muscular cont ...
, and then run obliquely upward and lateralward upon its under surface.
* The ''left phrenic'' passes behind the
esophagus
The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the ...
, and runs forward on the left side of the
esophageal hiatus
In human anatomy, the esophageal hiatus is an opening in the diaphragm through which the esophagus and the vagus nerve pass.
Structure
It is located in the right crus, one of the two tendinous structures that connect the diaphragm to the s ...
.
* The ''right phrenic'' passes behind the
inferior vena cava
The inferior vena cava is a large vein that carries the deoxygenated blood from the lower and middle body into the right atrium of the heart. It is formed by the joining of the right and the left common iliac veins, usually at the level of the ...
, and along the right side of the
foramen which transmits that vein. Near the back part of the
central tendon each vessel divides into a medial and a lateral branch.
* The ''medial branch'' curves forward, and anastomoses with its fellow of the opposite side, and with the
musculophrenic
The intercostal arteries are a group of arteries that supply the area between the ribs ("costae"), called the intercostal space. The highest intercostal artery (supreme intercostal artery or superior intercostal artery) is an artery in the human ...
and
pericardiacophrenic
The pericardiacophrenic artery is a long slender branch of the internal thoracic artery. It anastomoses with the musculophrenic and superior phrenic arteries.
Location
The pericardiacophrenic artery branches from the internal thoracic artery. ...
arteries.
* The ''lateral branch'' passes toward the side of the thorax, and anastomoses with the
lower intercostal
The intercostal arteries are a group of arteries that supply the area between the ribs ("costae"), called the intercostal space. The highest intercostal artery (supreme intercostal artery or superior intercostal artery) is an artery in the human ...
arteries, and with the
musculophrenic
The intercostal arteries are a group of arteries that supply the area between the ribs ("costae"), called the intercostal space. The highest intercostal artery (supreme intercostal artery or superior intercostal artery) is an artery in the human ...
. The lateral branch of the right phrenic gives off a few vessels to the
inferior vena cava
The inferior vena cava is a large vein that carries the deoxygenated blood from the lower and middle body into the right atrium of the heart. It is formed by the joining of the right and the left common iliac veins, usually at the level of the ...
; and the left one, some branches to the
esophagus
The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the ...
.
Function
The inferior phrenic arteries supply the diaphragm.
Each of the smaller vessels give off
superior suprarenal branches
The superior suprarenal artery is an artery in the abdomen. It is a branch of the inferior phrenic artery, itself a branch of the aorta. It supplies the adrenal gland.
Structure
The superior suprarenal artery is a branch of the inferior phreni ...
to the
suprarenal gland
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which ...
of its own side. The
spleen
The spleen is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The word spleen comes . and the
liver
The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for ...
also receive a few twigs from the left and right vessels respectively.
References
External links
* - "Posterior Abdominal Wall: Branches of the Abdominal Aorta"
* (#23)
{{Authority control
Arteries of the abdomen