The femoral sheath (also called the crural sheath) is a funnel-shaped downward extension of abdominal fascia within which the

femoral artery The femoral artery is a large artery in the thigh and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery and descends along the anteromedial part of the thigh in the femoral triangle. It enters ...

and

femoral vein In the human body, the femoral vein is the vein that accompanies the femoral artery in the femoral sheath. It is a deep vein that begins at the adductor hiatus (an opening in the adductor magnus muscle) as the continuation of the popliteal v ...

pass between the

abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

and the thigh. The femoral sheath is subdivided by two vertical partitions to form three compartments (medial, intermediate, and lateral); the medial compartment is known as the

femoral canal The femoral canal is the medial (and smallest) compartment of the three compartments of the femoral sheath. It is conical in shape. The femoral canal contains lymphatic vessels, and Adipose tissue, adipose and loose connective tissue, as well as - ...

and contains lymphatic vessels and a

lymph node A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that includ ...

, whereas the intermediate canal and the lateral canal accommodate the femoral vein and the femoral artery (respectively). Some neurovascular structures perforate the femoral sheath. Topographically, the femoral sheath is contained within the femoral triangle.

Structure

The femoral sheath is funnel-shaped fascial structure, with the wide end directed superior-ward. The femoral sheath is formed by an inferior-ward prolongation - posterior to the

inguinal ligament The inguinal ligament (), also known as Poupart's ligament or groin ligament, is a band running from the pubic tubercle to the anterior superior iliac spine. It forms the base of the inguinal canal through which an indirect inguinal hernia may ...

- of abdominal fascia, with transverse fascia being continued down anterior to the femoral vessels, and iliac fascia posterior to these. The femoral sheath is strengthened anteriorly by the iliopubic tract.'''' The narrowed inferior/distal end of the femoral sheath concludes by blending with the

tunica adventitia The tunica externa (Neo-Latin "outer coat"), also known as the tunica adventitia (Neo-Latin "additional coat"), is the outermost tunica (layer) of a blood vessel, surrounding the tunica media. It is mainly composed of collagen and, in arteries, i ...

of the femoral vessels about 4 cm inferior to the

.'''' The lateral wall of the sheath is vertical and is perforated by the lumboinguinal nerve; the medial wall is directed/oriented obliquely inferolaterally and is perforated by the

great saphenous vein The great saphenous vein (GSV; ) or long saphenous vein is a large, subcutaneous, superficial vein of the human leg, leg. It is the longest vein in the body, running along the length of the lower limb, returning blood from the foot, human leg, le ...

, and by

lymphatic vessel The lymphatic vessels (or lymph vessels or lymphatics) are thin-walled vessels (tubes), structured like blood vessels, that carry lymph. As part of the lymphatic system, lymph vessels are complementary to the cardiovascular system. Lymph vessel ...

. The femoral sheath is contained in the femoral triangle.

Compartments and contents

The sheath is divided by two vertical partitions which stretch between its anterior and posterior walls: * The (smallest) medial compartment is named the

, and contains some lymphatic vessels and a lymph gland embedded in a small amount of areolar tissue. * The intermediate compartment contains the

. * The lateral compartment contains the

Function

The femoral sheath allows for the

and the

to pass between the abdomen and the thigh.

Additional Images

File:Slide8GGGGG.JPG, Femoral sheath

References

External links

Photo and overview at gla.ac.uk
*

{{Portal bar, Anatomy Lower limb anatomy