Femoral sheath Anatomy

Femoral sheath

Femoral sheath Introduction: It is the fascia covering femoral vessels in front of thigh region.

1. Femoral sheath Gross

1. Length: 4 cm.

2. Shape: Conical (funnel).

1. Lateral wall is vertical.
2. Medial wall is obliquely directed downwards and laterally.

2. Femoral sheath Formation

1. Anterior wall: Fascia transversalis.
2. Posterior wall: Fascia iliaca.
3. Lateral and medial wall: Fusion of fascia transversalis and fascia iliacus.
4. Below it blends with tunica adventitia of blood vessels.

Read And Learn More: Anatomy Notes And Important Question And Answers

3. Communications

1. Superiorly opens into the abdomen.
2. Inferiorly merges with tunica adventitia of femoral vessels.

4. Contents of the femoral sheath (from medial to lateral) are described as the contents of each compartment.

1. Medial compartment: Femoral Canal Contains FCC

1. Fibrofatty tissue
2. Cloquet lymph nodes
3. Cloquet lymphatics

2. Intermediate compartment—venous compartment:

1. Femoral vein and its
2. Tributary—great saphenous vein

3. Lateral compartment—arterial compartment

1. Femoral artery, and
2. Femoral branch of genitofemoral nerve.

5. Structures piercing the various walls

1. Anterior wall is pierced by

1. Superficial epigastric artery,
2. Superficial circumflex iliac artery, and
3. Superficial external pudendal artery.
4. Deep external pudendal artery—deep branch of femoral artery.

2. Lateral wall: Femoral branch of genitofemoral nerve

3. Medial wall

1. Lymph vessels, and
2. Great saphenous vein.

6. Femoral sheath Relations

1. Femoral sheath Anterior

1. Skin,
2. Superficial fascia,
3. Fascia lata (deep fascia), and
4. Inguinal ligament.

2. Femoral sheath Posterior

1. Nerve to pectineus,
2. Muscles deep to nerve to pectineus (from lateral to medial), Psoas major, and Pectineus.
3. Structure deep to above muscles—capsule of hip joint.

3. Femoral sheath Lateral: Femoral nerve with its branches

4. Femoral sheath Medial: Adductor longus

7.  Femoral canal  Division: It is divided into three compartments by two vertical septa.

1. Medial compartment: It is also called the femoral canal.

1. Fatty connective tissue.
2. Cloquet lymph node which drains Male: Glans penis, Female: Clitoris.
3. Cloquet lymph vessels.

2. Intermediate or venous compartment which contains femoral vein.

3. Lateral or arterial compartment which contains

1. Femoral artery, and
2. Femoral branch of genitofemoral nerve.

8. Femoral canal  Function: It allows freedom for the femoral vessels to glide in and out beneath the inguinal ligament during movements of the hip joint.

9. Femoral canal  Age changes: It is rudimentary in newborns. It is elongated after 1 year.

10. Femoral sheath Applied anatomy

Femoral canal is a potential weak point through which abdominal contents pass through.

Femoral hernia is a protrusion of abdominal contents through the femoral canal. It is common in females because of wider femoral ring. The femoral ring is wider in female due to

1. Wider pelvis, and
2. Smaller vessels.

Any swelling lateral and below the pubic tubercle is most likely to be femoral hernia.

The direction of the femoral hernia is:

1. Downwards through the femoral canal,
2. Forwards through the saphenous opening,
3. Upwards along with superficial epigastric and superficial circumflex iliac vessels, and
4. Laterally towards anterior superior iliac spine.

The femoral hernia is reduced in the reverse direction as medially, downwards, backwards and upwards. Strangulated hernia resembles an inflamed deep inguinal lymph node.

The pubic branch of inferior epigastric artery is a branch of external iliac artery.It runs to reach pubic symphysis. Normally, it runs lateral to femoral ring which is safe. If it passes medial to femoral ring, the course is said to be abnormal.Surgeons need to keep the abnormal course of the artery in mind while operating on femoral hernia.

Abnormal obturator artery: Obturator artery usually is a branch of the internal iliac artery. It gives a pubic branch which anastomoses with the pubic branch of the inferior epigastric artery. Occasionally, this anastomosis is large and the obturator artery then appears to be a branch of the inferior epigastric. The abnormal artery usually passes lateral to the femoral canal. It is safe in an operation to enlarge the femoral ring. Sometimes, the abnormal obturator artery may lie along the medial margin of the femoral ring, i.e. along the free margin of the lacunar ligament. Such an artery is likely to be cut if an attempt is made to enlarge the femoral ring.

This abnormal rare position is more frequent in males than in females. The incidence is 1:1000.

Femoral Canal

Femoral Canal Introduction: It is a potential weakness present in the smallest medial compartment of the femoral sheath.

1. Femoral Canal Features

1. It is the smallest, shortest and relatively empty compartment.
2. It is the medial or lymphatic compartment of the femoral sheath.

2. Femoral Canal Gross

1. Length: 2 cm
2. Diameter: About 1 cm
3. Shape: Oval. It has a base and an apex.
4. Base is wider and is called the femoral ring. It is the mouth of the femoral canal. It admits the tip of the little finger and is known as the femoral ring.
5. Apex is narrow.

3. Femoral Canal Attachments and relations: The wall is firmly attached

1. Anteriorly to inguinal ligament,

2. Posteriorly to

1. Pectineal ligament and
2. Fascia covering pectineus.

3. Medially to lacunar ligament, and

4. Femoral Canal Laterally to the septum. It separates femoral canal from venous compartment.

4. Femoral Canal Contents: Femoral Canal Contains

Fibrofatty tissue

Cloquet lymph nodes: There are two deep inguinal lymph nodes in relation to inguinal canal.

One at the inguinal ring and another in the inguinal canal.

Cloquet lymphatics

1. Afferent lymphatics are from

1. Superficial inguinal nodes,
2. Popliteal nodes,
3. Glans penis in males
4. Clitoris in females , and
5. Deep lymphatics of the lower limb.

2. Efferent lymphatics to external iliac group of lymph nodes.

5. Femoral Canal Functions

1. It is the route by which the efferent lymph vessels from the deep inguinal nodes pass to the abdomen
2. It provides a ‘dead space’. The space allows expansion of the femoral vein during increased venous return.

6. Femoral Canal Applied anatomy

Femoral Hernia

Femoral Hernia Introduction: It is the protrusion of abdominal contents through the femoral canal.

Gender: It is more common in female because of wider pelvis and narrower vessels.

Factors precipitating femoral hernia

1. Increased intra-abdominal pressure,
2. Chronic cough,
3. Constipation,
4. Multiparous woman ,
5. Tumours in the abdomen, and
6. Old age.

Femoral Hernia Diagnosis: A swelling 4 cm below and lateral to pubic tubercle that increases on increased intra-abdominal pressure goes in favour of femoral hernia.

As the hernia passes down through the narrow femoral ring, it is in a position of considerable danger. The sharp crescentic edge of the lacunar ligament may interfere with its blood supply.

Herniorrhaphy: In repair of the strangulated femoral hernia, position of accessory obturator artery should be kept in mind.

The direction of the femoral hernia is

1. Downwards through the femoral canal,
2. Forwards through saphenous opening,
3. Upwards along with superficial epigastric and superficial circumflex iliac vessels, and
4. Laterally towards anterior superior iliac spine.

The femoral hernia is reduced in reverse direction as medially, downwards, backwards and upwards.