Inguinal hernias and canal

Question 1

the inguinal canal serves as a pathway

Answer 1

by which structures can pass from the abdominal wall to the external genitalia.

Question 2

the opening of the inguinal canal is located ………… to the inferior epigastric artery

Answer 2

Question 3

development of the inguinal canal

Answer 3

During development, the tissue that will become gonads (either testes or ovaries) establish in the posterior abdominal wall, and descend through the abdominal cavity. A fibrous cord of tissue called the gubernaculum attaches the inferior portion of the gonad to the future scrotum or labia, and guides them during their descent.

The inguinal canal is the pathway by which the testes (in an individual with an XY karyotype) leave the abdominal cavity and enter the scrotum. In the embryological stage, the canal is flanked by an out-pocketing of the peritoneum (processus vaginalis) and the abdominal musculature.

The processus vaginalis normally degenerates, but a failure to do so can cause an indirect inguinal hernia, a hydrocele, or interfere with the descent of the testes. The gubernaculum (once it has shortened in the process of the descent of the testes) becomes a small scrotal ligament, tethering the testes to the scrotum and limiting their movement.

Question 4

Mid-inguinal Point and Midpoint of the Inguinal Ligament

Answer 4

These two terms are mentioned frequently in this article, and are often (mistakenly) used interchangeably

Question 5

Mid-inguinal point –

Answer 5

halfway between the pubic symphysis and the anterior superior iliac spine. The femoral pulse can be palpated here.

Question 6

Midpoint of the inguinal ligament –

Answer 6

halfway between the pubic tubercle and the anterior superior iliac spine (the two attachments of the inguinal ligament). The opening to the inguinal canal is located just above this point.

Question 7

two openings of the inguinal canal

Answer 7

superifical (near the end) and deep (at the beginning, lateral to the inferior epigastric vessel) rings

Question 8

Anterior wall –

Answer 8

aponeurosis of the external oblique, reinforced by the internal oblique muscle laterally.

Question 9

Posterior wall –

Answer 9

transversalis fascia.

Question 10

Roof –

Answer 10

transversalis fascia, internal oblique, and transversus abdominis.

Question 11

Floor –

Answer 11

inguinal ligament (a ‘rolled up’ portion of the external oblique aponeurosis), thickened medially by the lacunar ligament.

Question 12

borders of the inguinal canal

Answer 12

Question 13

saggital veiw of the inguinal canal, showing borders

Answer 13

Question 14

The deep (internal) ring

Answer 14

is found above the midpoint of the inguinal ligament. which is lateral to the epigastric vessels. The ring is created by the transversalis fascia, which invaginates to form a covering of the contents of the inguinal canal

Question 15

The superficial (external) ring

Answer 15

ring marks the end of the inguinal canal, and lies just superior to the pubic tubercle. It is a triangle shaped opening, formed by the evagination of the external oblique, which forms another covering of the inguinal canal contents. This opening contains intercrural fibres, which run perpendicular to the aponeurosis of the external oblique and prevent the ring from widening.

Question 16

contents fo the inguinal canal

Answer 16

Saskia really is grey

Spermatic cord (biological males only) – contains neurovascular and reproductive structures that supply and drain the testes. See here for more information.

Round ligament (biological females only) – originates from the uterine horn and travels through the inguinal canal to attach at the labia majora.

Ilioinguinal nerve – contributes towards the sensory innervation of the genitalia

• Note: only travels through part of the inguinal canal, exiting via the superficial inguinal ring (it does not pass through the deep inguinal ring)
• This is the nerve most at risk of damage during an inguinal hernia repair.

Genital branch of the genitofemoral nerve – supplies the cremaster muscle and anterior scrotal skin in males, and the skin of the mons pubis and labia majora in females.

Question 17

indirect hernia

Answer 17

• most common type of inguinal hernia
• cause: failure of processus vaginalis to regress (extent to which sac herniates depends on the amount of PR still present)
• hernia enters the inguinal canal through the deep inguinal ring (lateral to the inferior epigastric artery)
• then enters the testess via the superical inguinal ring

Question 18

direct inguinal hernia

Answer 18

• enters the inguinal canal via the superifical ring (medial to the infeiror epigastric artery)
• within Hesselbach triangle
• occurs as a result of weakeness in the floor of the inguinal canal
• usually occurs in adulthood- due to weakening of abdominal musculature
• sac not covered with contents of canal

Question 19

what forms the medial border of hesselbach triangle

Answer 19

lateral border of rectus abdominus

Question 20

what forms the latral border of the femoral ring

Answer 20

femoral vein

Question 21

what structure fors the floor of the inguinal canal

Answer 21

the inguinal ligament

Question 22

what path does a direct inguinal ligament follow as it leaves the abdomen

Answer 22

passes through a weakness in hesselbachs triangle

Question 23

what is the location of the linea alba

Answer 23

verticle in the midline from xiphoid process to pubic symphysis

Question 24

what ar the borders of hesselbachs triagnle

Answer 24

inguinal ligament, inferior epigastric vessels, lateral border of the rectus abdominus muscles

Question 25

below the arcuate line the posteiror surface of the rectus abdominus muscles are in contact with which structures

Answer 25

transversalis fascia

Question 26

what type of hernia may be precipited by a weakened conjoint tendon

Answer 26

direct inguinal hernia

Question 27

which hernia affects young children and usually spontaneously resolves in first few years?

Answer 27

umbilicus