The Inguinal Region/Canal

Question 1

Why is the anatomy of the inguinal region/canal clinically important?

Answer 1

Due to the frequency of inguinal hernae.

Question 2

What forms the inguinal ligament? How?

Answer 2

The aponeurosis of the external oblique; by folding over on itself forming a taut ligament-like structure.

Question 3

To which bony structures does the inguinal ligament attach?

Answer 3

Superolaterally to the anterior superior iliac spine of the hip bone, and inferomedially to the pubic tubercle.

Question 4

A deficiency in each of the three layers on the anterolateral abdominal wall, in the region of the inguinal ligament, forms what specific passage?

Answer 4

The inguinal canal - an obliquely flattened passageway.

Question 5

In which layer is the superficial inguinal ring formed?

Answer 5

The aponeurosis of the external oblique - the outermost (superficial) layer.

Question 6

In which layer is the deep inguinal ring formed?

Answer 6

It is a slit in the fascia transversalis.

Question 7

What structure forms the floor of the inguinal canal?

Answer 7

The inguinal ligament.

Question 8

What structure forms the posterior wall of the inguinal canal?

Answer 8

The conjoint tendon (joined aponeuroses of the internal oblique and transversus abdominis).

Question 9

What passes through this inguinal canal in the neonatal male?

Answer 9

TESTIS BALLS

Question 10

In the adult male what structure is found within the inguinal canal?

Answer 10

Spermatic cord

Question 11

In the adult female what structure is found within the inguinal canal?

Answer 11

The Round Ligament

Question 12

Which layer(s) of the anterior abdominal wall contribute to the sheaths of the spermatic cord?

Answer 12

All but the transversus abdominis.

Question 13

What does each participating layer of the anterior abdominal wall contribute to the spermatic cord?

Answer 13

External oblique - external spermatic fascia; internal oblique - cremasteric muscle and/or fascia; transversus abdominis - nil; fascia transversalis - internal spermatic fascia.

Question 14

Which layer of the anterior abdominal wall does not contribute to the spermatic cord?

Answer 14

Transversus abdominis.

Question 15

What are the main components found within the spermatic cord?

Answer 15

The ductus deferens, testicular a., pampiniform plexus of (testicular) veins.

Question 16

What feature of embryological development allows the formation of a congenital hernia?

Answer 16

The processus vaginalis (a finger-like extension of the peritoneum that extends down into the scrotum via the inguinal canal.

Question 17

In what age groups is the formation of a congenital hernia common?

Answer 17

Up to the early 30’s

Question 18

What is the actual function of the processus vaginalis?

Answer 18

It provides a serous (slippery) lining for the inside aspect of the scrotal wall and the visceral surface of the testicle for friction-free movement.

Question 19

What typically extends from the body cavity in a hernia?

Answer 19

A loop of small intestine.

Question 20

What is the clinical implication of an inguinal hernia?

Answer 20

The loop of bowel may become trapped in the inguinal canal, squeezed by intra-abdominal pressure on the canal walls and cause loss of blood supply - gangrene may ensue.

Question 21

How does an acquired inguinal hernia differ from the congenital type?

Answer 21

An inguinal hernia slides down the oblique inguinal canal due to the presence of a patent processus vaginalis (passing through the anterior abdominal wall indirectly), the acquired inguinal hernia protrudes directly through a defect that develops in the posterior wall of the inguinal canal (the conjoint tendon) and out through the superficial inguinal ring.

Question 22

Through what component of the inguinal canal does the hernia protrude?

Answer 22

The superficial inguinal ring after penetrating the posterior wall (conjoined tendon).

Question 23

Where would the inferior epigastric a. pulse be found in each type of herniation?

Answer 23

In the congenital (indirect) inguinal hernia the arterial pulse is medial to the hernia whereas in the acquired (direct) inguinal hernia the pulse is felt lateral to the hernia.

Question 24

How do inguinal herniae differ in presentation from femoral herniae?

Answer 24

Inguinal hernia present above the inguinal ligament whereas a femoral hernia presents under the inguinal ligament.

Question 25

Name the boundaries of the inguinal triangle.

Answer 25

Lateral: inferior epigastric a.; medial: lateral border of the rectus abdominis; inferior: inguinal ligament.

Question 26

What structure(s) typically traverse this space in the normal condition?

Answer 26

The spermatic cord passes through the triangle just above the inferior boundary - the inguinal ligament.

Question 27

Where is the location of the deep inguinal ring with relation to the inferior epigastric artery?

Answer 27

The deep inguinal ring is lateral to the inferior epigastric a.

Question 28

Where is the inferior epigastric artery going?

Answer 28

Up into the posterior aspect of the rectus sheath, between it the posterior leaf of the sheath and the rectus abdominis muscle, gaining access via the arcuate line.