Hernias

Question 0

What are the key features of a direct inguinal hernia?

Answer 0

“ACQUIRED”

~1/3

Protrudes through weakened area in the transversalis fascia (Hesselbach’s triangle) and then through the superficial ring

Bowel is MEDIAL to inferior epigastric vessels

Hernial sac parallels spermatic cord (rarely enters scrotum)

Question 1

What is the definition of a hernia?

Answer 1

Protrusion of organ/fascia of an organ through a weakness in the muscle of surrounding tissue wall (protrudes out of body cavity in which it normally lies)

Question 2

What are the borders of Hesselbach’s triangle?

Answer 2

Inferior = medial 1/2 of inguinal ligament 
Medial = lower lateral border of rectus abdominis 
Lateral = inferior epigastric artery

Question 3

What are the key features of an indirect inguinal hernia?

Answer 3

“CONGENITAL”

~2/3

Protrudes through deep inguinal ring, travels down inguinal canal, and through the superficial ring

Bowel LATERAL to inferior epigastric vessels

Usually due to a patent processus vaginalis (used for the passage of the testicle during development)

Pushes through all three fascial coverings of spermatic cord to form hernial sac

Commonly passes into the scrotum/labium majus

Question 4

What are the key features of epigastric hernias?

Answer 4

Protrudes through the midline between the xiphoid process & the umbilicus (through the linea alba)

In adults, can be caused by obesity/pregnancy

Question 5

What are the key features of umbilical hernias?

Answer 5

Protrudes through umbilical ring due to increased intra-abdominal pressure and the presence of weakness/incomplete closure of the abdominal wall (after ligation of the umbilical cord at birth)

In adults occurs in women/obese

Question 6

What are the key features of femoral hernias?

Answer 6

Protrudes through femoral canal - appears as a mass in the femoral triangle

Bounded by the femoral vein (laterally) and the lacunar ligament (medially)

Can pass inferiorly through the saphenous opening into the subcutaneous tissue of the thigh (enlarges)

Compresses the contents of the femoral canal (loose connective tissue, fat, lymphatics) and distends the wall of the canal

Question 7

What is the definition of a strangulated hernia?

Answer 7

Sharp, rigid boundaries of femoral ring constrict the blood vessels of the bowel, causing ischaemia

Question 8

What is the definition of an incarcerated hernia?

Answer 8

Hernia cannot be reduced or pushed back into place without a lot of external effort.

Question 9

How can inguinal and femoral hernias be differentiated?

Answer 9

Almost impossible to differentiate direct and indirect inguinal hernias clinically

Place finger over femoral canal (one finger medial to femoral artery) and ask patient to cough -> if hernia remains reduced it is femoral, if inguinal it will reappear as an obvious swelling

Harder to push bowel back up femoral canal rather than push through superficial ring

Femoral: below inguinal ligament
Inguinal: above inguinal ligament

Question 10

What are the borders and contents of the inguinal canal?

Answer 10

Anterior wall = external oblique aponeurosis + internal oblique laterally

Posterior wall = transversalis fascia + conjoint tendon/inguinal falx (internal oblique + transversus abdominis aponeuroses) and reflected inguinal ligament medially

Roof = transversalis fascia (laterally) + internal oblique and transversus abdominis musculo-aponeurotic arches (centrally) + medial crus of external oblique aponeurosis (medially)

Floor = iliopubic tract (laterally) + infolded inguinal ligament (centrally) + lacunar ligament (medially)

Contents: ilio-inguinal nerve
Male - spermatic cord
Female - round ligament of uterus