W7: GI Herniation: Anatomy & Clinical Flashcards
What are 4 causes of a hernia?
- structural weakness
- increased pressure
- sites where surgical incisions are made
- inherited collagen disorders
What can cause a congenital diaphragmatic hernia?
If oesophagus grows slower than normal in foetus then stomach can be drawn up into chest
What 4 factors can increase intra-abdominal pressure?
- chronic cough
- pregnancy
- strenuous activity
- straining during bowel/urinary movements
What does the linea semilunaris mark the separation of?
the anterior abdominal wall and the lateral abdominal wall
What does the inguinal ligament mark the anterior boundary between?
the abdomen and the thigh
From what two points does the inguinal ligament connect?
ASIS to pubic tubercle
Why is inguinal ligament not a true ligament?
Because it is actually an inferior thickening of external oblique muscle
The medial half of the inguinal ligament curves to form what structure?
The floor of the inguinal canal
Through what structure is there abdominal communication with the the perineum?
Inguinal canal
What is name of the the space that allows abdominal structure communication to thigh and vice versa?
Subinguinal space
What is the name of the entrance of the inguinal canal?
Deep inguinal ring
What is the name of the exit of the inguinal canal?
Superficial inguinal ring
What 2 structures does the inguinal canal contain in everyone and what 2 extra structures does it contain specific to males and females?
- Blood and lymphatic vessels
- ilioinguinal nerve
- spermatic cord (males)
- round ligament of the uterus (female)
Where do the testes develop in the foetus?
On the posterior abdominal wall
What is the gubernaculum and what happens during embryonic development?
- fibrous cord
- contracts and also shortens in size in relation to growth of embryo
What lies between the parietal peritoneum and the transversus abdominis muscle?
Transversalis fascia
What does the gubernaculum join together?
Attaches inferior side of the testes to the body wall
What does the gubernaculum become in the female?
Round ligament of the uterus
What does gubernaculum become in the male?
Testicular ligament
What is the name of the outpouching of the peritoneum created by the descent of the testes in embryonic development?
Vaginal process
What happens to the vaginal process in adults?
Two borders of the processus vaginalis fuse together to form a pocket of peritoneal fluid called the tunica vaginalis
What is the function of the tunica vaginalis in which the testes lie?
reduce friction from movement of testes up and down in adult
What embryonic development failure in descent of the testes can be a predisposing factor for gut herniation?
If the two borders of the vaginal process fail to join together and you have a patent vaginal process
Where do the layers of the spermatic cord originate from?
layers of the abdominal wall are pulled down along with testis when they descend
What does the subcutaneous tissue layer in the abdominal wall become in the spermatic cord?
dartos muscle/fascia
What does the external oblique muscle and fascia layer in the abdominal wall become in the spermatic cord?
External spermatic fascia
What does the internal oblique muscle layer in the abdominal wall become in the spermatic cord?
Cremaster muscle
What does the fascia of the internal oblique muscle layer in the abdominal wall become in the spermatic cord?
Cremasteric fascia
What does the transversalis fascia layer in the abdominal wall become in the spermatic cord?
Internal spermatic fascia
What muscle in the abdominal wall does not form part of the spermatic cord when the testis descend in embryonic development?
Transversus abdominis muscle
What is the conjoint tendon?
combination of internal oblique and trasnversus abdominis aponeurosis
What are the 3 borders of Hesselbach’s Triangle? (bottom, upper and inside)
- bottom -> inguinal ligament
- upper -> inferior epigastric artery
- inside -> lateral border of rectus abdominis
What is Hesselbach’s Triangle a site of?
Site of direct inguinal herniation
What is the deep inguinal ring a site of?
Indirect inguinal herniation
Of Hesselbech’s triangle and the deep inguinal ring, which is medial to and which is lateral to the inferior epigastric artery?
Hesselbach’s triangle -> medial
Deep inguinal ring -> lateral
What is the difference between a direct inguinal hernia and an indirect inguinal hernia?
Direct hernia pushes directly through abdominal wall whereas indirect hernia uses inguinal canal
Where does herniation lie in relation to spermatic cord in direct inguinal herniation?
Parallel to spermatic cord
Where does herniation lie in relation to spermatic cord in indirect inguinal herniation?
Within spermatic cord
Which type of inguinal hernia passes through Hesselbech’s Triangle before going through the superficial ring?
Direct inguinal hernia
What two structures (muscle and aponeurosis) form the anterior wall of the inguinal canal? (which just laterally?)
- external oblique aponeurosis
- internal oblique muscle -> only lateral
What two structures form the posterior wall of the inguinal canal? (laterally and medially)
- transversalis fascia -> laterally
- conjoint tendon -> medially
What three structures form the roof of the inguinal canal? (laterally, centrally and medially)
- Trasnversalis fascia -> laterally
- arches of internal oblique and transversus abdominis aponeurosis -> centrally
- external oblique aponeurosis -> medially
What lies below the inguinal canal?
Subinguinal space
What 4 structures pass through the subinguinal space?
- nerves
- lymphatics
- hip flexors
- femoral artery and vein
What does the femoral canal contain?
lymphatics
What is the name given to the area of innate weakness where both inguinal and femoral hernias can occur?
Myopectineal orifice
In terms of surface anatomy, where is the deep inguinal ring located?
halfway along the inguinal ligament
List 9 types of hernia.
- umbilical
- lumbar
- inguinal
- femoral
- epigastric
- spigelian
- parastomal
- incisional
- port-site
Where does a spigelian hernia occur?
Weakness in the spigelian fascia between transversus and rectus abdominal muscles that comes out at the semilunar line
What is a port-site hernia?
Hernia that occurs at port-sites after a laparoscopic surgery
What are the three classifications of hernia and what does each mean?
-reducible -> hernia can be pushed back in
-incarcerated/irreducible -> hernia can’t be manipulated back into abdo
-strangulated -> vascular supply to hernia is cut off and so is ischaemic and gangrenous
-
What are three possible causes of paraumbilical hernias?
abdo stretching due to
- obesity
- pregnancy
- ascites
What is the usual management for umbilical and paraumbilical hernias?
surgical
What is the usual cause of umbilical hernias in adults?
persistent elevation of intra-abdo pressure
What are the 6 structures contained in the the spermatic cord?
- vas deferens
- 3 arteries: testicular artery, artery to the vas and cremasteric artery
- Pampiniform plexus (veins)
- lymphatics
- nerves: genital branch of genitofemoral nerve and sympathetic twigs
- remains of Processus Vaginalis (tunica vaginalis)
How does inguinal hernia present and how is it examined?
- swelling superior to and medial to pubic tubercle (groin swelling) that goes away when lying down
- examined by having patient cough and feeling it when they cough
What forms the anterior border of the femoral ring?
Inguinal ligament
What forms the posterior border of the femoral ring?
Iliopectineal ligament
What forms the lateral border of the femoral ring?
femoral vein
What forms the medial border of the femoral ring?
lacunar ligament
