Hernia
1. What are the different sites of hernia. Describe inguinal canal and inguinal hernia.
Definition
Hernia is a protrusion of bowel or anyother organ through a weak point in the musculature of the body cavities, usually the abdominal cavity
Sites of Hernia
Inguinal hernia
Weak point in the inguinal canal
Femoral hernia
The weak point is the femoral canal through which the femoral artery vein, and lymph vessels pass from the pelvis to the thigh
Umbilical hernia
Through the umbilicus where the umbilical blood vessels from the placenta enter the foetus
Incisional hernia
Through the fibrous tissue in the scar of an operation or a wound
Diaphragmatic hernia
Intestines enter the thoracic cavity through a weak point in the diaphragm
Hiatus hernia
Part of the stomach enters the thoracic cavity through the oesophageal opening in the diaphragm
Anatomy - Inguinal Canal
o The inguinal canal is situated in the inguinal region
o Parallel to the inguinal ligament
o 2.5 cm to 3 cm long
o consists of deep inguinal ring
o superficial inguinal ring near the pubic tubercle
o The floor is formed by the inguinal ligament
o The posterior wall is formed by the internal oblique, the transversalis abdominis muscle and fascia
o The anterior wall is formed by the external obliquel laterally and the conjoined tendon medially
o Medial to the internal ring passes the deep epigastric artery from the external iliac artery to the rectus muscle
The contents of the inguinal canal are:-
o The spermatic cord with vas deferens, the spermatic veins, the testicular artery, the ilioinguinal nerve, the round ligament in the female.
The weak point may be the deep inguinal ring or the posterior wall.
The hernia travels along the inguinal canal and comes out into the sucutaneous plane and into the scrotum / the labium majus through the superficial inguinal ring.
While the omentum or intestines herniate they push the layers of the abdominal wall in front of them. The bag formed by the peritoneum is called the sac of the sac. The sac is described as having a neck - a narrowed portion and a fundus - an expanded portion.
Protrusion through the deep inguinal ring - indirect inguinal hernia - lateral to the inferior epigastric artery
protrusion through the posterior wall of the canal - direct inguinal hernia - medial to the inferior epigastric artery
