Femoral triangle
Encyclopedia
The femoral triangle is an anatomical region of the upper inner human
thigh
.
Its floor is formed by the pectineus and adductor longus muscles medially and iliopsoas muscle laterally. Its roof is formed by the fascia lata
.
The femoral triangle is shaped like the sail of a ship.
Its boundaries can be remembered using the mnemonic
, "SAIL" for Sartorius, Adductor longus and Inguinal Ligament.
to medial
):
1) Terminal part of the femoral nerve
and its branches; the femoral branch of genitofemoral nerve
, which innervates the skin covering the roof of the femoral triangle; and the Lateral cutaneous nerve of thigh
, which later divides into anterior and posterior branches.
2) The three compartments of the femoral sheath
(From lateral
to medial
):
and peripheral angioplasty is often performed by entering the femoral artery at the femoral triangle. Heavy bleeding in the leg can be stopped by applying pressure to points in the femoral triangle. Another clinical significance of the femoral triangle is that the femoral artery is positioned at the midinguinal point (midpoint between the pubic symphysis and the anterior superior iliac spine); medial to it lies the femoral vein. Thus the femoral vein, once located, allows for femoral venopuncture. Femoral venopuncture is useful when there are no superficial veins that can be aspirated in a patient, in the case of collapse. The positive pulsation of the femoral artery signifies that the heart is beating and also blood is flowing to the lower extremity.It is also necessary to appreciate clinically that this is a case where the nerve is more lateral than the vein. In most other cases the a nerve (relative to its associated artery and vein)would be the deepest or more medial followed by the artery and then the vein. But in this case it is the opposite. This must be remembered when venous or arterial samples are required from the femoral vessels. The order of this neurovascular bundle can be remembered using the mnemonic
, "NAVY" for Nerve, Artery, Vein, Y -fronts (the British term of a style of men's underwear with a "Y" shaped front that acts as a fly). The "Y" is midline (corresponding with the penis) and the mnemonic always reads from the outside - in, so that the Femoral Nerve
is always lateral. An alternate to this mnemonic is "NAVaL" for Nerve, Artery, Vein, and Lymph, to include the deep inguinal lymph nodes
located medial to the Femoral vein
.
Human
Humans are the only living species in the Homo genus...
thigh
Thigh
In humans the thigh is the area between the pelvis and the knee. Anatomically, it is part of the lower limb.The single bone in the thigh is called the femur...
.
Boundaries
It is bounded by:- (superiorlyAnatomical terms of locationStandard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
) the inguinal ligamentInguinal ligamentThe inguinal ligament is a band running from the pubic tubercle to the anterior superior iliac spine. Its anatomy is very important for operating on hernia patients.-Anatomy:... - (mediallyAnatomical terms of locationStandard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
) the medial border of the adductor longus muscle - (laterallyAnatomical terms of locationStandard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
) medial border of the sartoriusSartorius muscleThe Sartorius muscle – the longest muscle in the human body – is a long thin muscle that runs down the length of the thigh. Its upper portion forms the lateral border of the femoral triangle.-Origin and insertion:...
muscle
Its floor is formed by the pectineus and adductor longus muscles medially and iliopsoas muscle laterally. Its roof is formed by the fascia lata
Fascia lata
-Thickness:It is an investment for the whole of the thigh, but varies in thickness in different parts.Thus, it is thicker in the upper and lateral part of the thigh, where it receives a fibrous expansion from the Glutæus maximus, and where the Tensor fasciæ latæ is inserted between its layers; it...
.
The femoral triangle is shaped like the sail of a ship.
Its boundaries can be remembered using the mnemonic
Mnemonic
A mnemonic , or mnemonic device, is any learning technique that aids memory. To improve long term memory, mnemonic systems are used to make memorization easier. Commonly encountered mnemonics are often verbal, such as a very short poem or a special word used to help a person remember something,...
, "SAIL" for Sartorius, Adductor longus and Inguinal Ligament.
Contents
It is important as a number of vital structures pass through it, right under the skin. The following structures are contained within the femoral triangle (from lateralAnatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
to medial
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
):
1) Terminal part of the femoral nerve
Femoral nerve
The femoral nerve, the largest branch of the lumbar plexus, arises from the dorsal divisions of the ventral rami of the second, third, and fourth lumbar nerves...
and its branches; the femoral branch of genitofemoral nerve
Genitofemoral nerve
In human anatomy, the genitofemoral nerve originates from the upper part of the lumbar plexus of spinal nerves. Its roots are L1 and L2 .The genitofemoral nerve is responsible for both the efferent and afferent limbs of the cremasteric reflex...
, which innervates the skin covering the roof of the femoral triangle; and the Lateral cutaneous nerve of thigh
Lateral cutaneous nerve of thigh
The lateral cutaneous nerve of the thigh is a cutaneous nerve that innervates the skin on the lateral part of the thigh.-Structure:...
, which later divides into anterior and posterior branches.
2) The three compartments of the femoral sheath
Femoral sheath
The femoral sheath is formed by a prolongation downward, behind the inguinal ligament, of the fasciæ which line the abdomen, the transversalis fascia being continued down in front of the femoral vessels and the iliac fascia behind them....
(From lateral
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
to medial
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
):
- femoral arteryFemoral arteryThe femoral artery is a general term comprising a few large arteries in the thigh. They begin at the inguinal ligament and end just above the knee at adductor canal or Hunter's canal traversing the extent of the femur bone....
and its branches - femoral veinFemoral veinIn the human body, the femoral vein is a blood vessel that accompanies the femoral artery in the femoral sheath. It begins at the adductor canal and is a continuation of the popliteal vein...
s and its tributaries - femoral canalFemoral canalThe femoral sheath has three compartments. The lateral compartment contains the femoral artery, the intermediate compartment contains the femoral vein, and the medial and smallest compartment is called the femoral canal. The femoral canal contains efferent lymphatic vessels and a lymph node...
, Which contains lymphatic vessels and some lymph nodes (Specifically, the deep inguinal lymph nodesDeep inguinal lymph nodesThe deep inguinal lymph nodes are located medial to the femoral vein and under the cribriform fascia. There are approximately 3 to 5 deep nodes...
)
Clinical significance
Since the femoral triangle provides easy access to a major artery, coronary angioplastyAngioplasty
Angioplasty is the technique of mechanically widening a narrowed or obstructed blood vessel, the latter typically being a result of atherosclerosis. An empty and collapsed balloon on a guide wire, known as a balloon catheter, is passed into the narrowed locations and then inflated to a fixed size...
and peripheral angioplasty is often performed by entering the femoral artery at the femoral triangle. Heavy bleeding in the leg can be stopped by applying pressure to points in the femoral triangle. Another clinical significance of the femoral triangle is that the femoral artery is positioned at the midinguinal point (midpoint between the pubic symphysis and the anterior superior iliac spine); medial to it lies the femoral vein. Thus the femoral vein, once located, allows for femoral venopuncture. Femoral venopuncture is useful when there are no superficial veins that can be aspirated in a patient, in the case of collapse. The positive pulsation of the femoral artery signifies that the heart is beating and also blood is flowing to the lower extremity.It is also necessary to appreciate clinically that this is a case where the nerve is more lateral than the vein. In most other cases the a nerve (relative to its associated artery and vein)would be the deepest or more medial followed by the artery and then the vein. But in this case it is the opposite. This must be remembered when venous or arterial samples are required from the femoral vessels. The order of this neurovascular bundle can be remembered using the mnemonic
Mnemonic
A mnemonic , or mnemonic device, is any learning technique that aids memory. To improve long term memory, mnemonic systems are used to make memorization easier. Commonly encountered mnemonics are often verbal, such as a very short poem or a special word used to help a person remember something,...
, "NAVY" for Nerve, Artery, Vein, Y -fronts (the British term of a style of men's underwear with a "Y" shaped front that acts as a fly). The "Y" is midline (corresponding with the penis) and the mnemonic always reads from the outside - in, so that the Femoral Nerve
Femoral nerve
The femoral nerve, the largest branch of the lumbar plexus, arises from the dorsal divisions of the ventral rami of the second, third, and fourth lumbar nerves...
is always lateral. An alternate to this mnemonic is "NAVaL" for Nerve, Artery, Vein, and Lymph, to include the deep inguinal lymph nodes
Deep inguinal lymph nodes
The deep inguinal lymph nodes are located medial to the femoral vein and under the cribriform fascia. There are approximately 3 to 5 deep nodes...
located medial to the Femoral vein
Femoral vein
In the human body, the femoral vein is a blood vessel that accompanies the femoral artery in the femoral sheath. It begins at the adductor canal and is a continuation of the popliteal vein...
.