Abdominal Wall Herias Flashcards
What is a Hernia?
A protrusion of part of the abdominal contents behind the normal confines of the abdominal wall
What are the 3 parts of a hernia
- Contents of the sac (Any structure within abdominal cavity)
- The sac (pouch of peritoneum)
- Coverings of the sac (Layers of abdominal walls through which hernia has passed)
What do we call a Hernia that gets stuck?
What are some signs and symptoms
Incarcerated
- Pain
- Can’t be moved (Pushed inwards)
- Nausea and vomiting (Bowel obstruction)
- Systemic problems if bowel becomes ischaemic (Strangulated- disrupted blood supply)
- Bowel leaks where tissue is broken down (Peritonitis)
List some signs and symptoms of a hernia
- Fulness or swelling
- Protrusion gets larger when intra abdominal pressure increases
- Ache/ discomfort
Name 3 causes of an increase in intra-abdominal pressure
- Obesity
- Weightlifting
- Chronic cough/ constipation
List 4 main types of hernias
Which is most common?
- Inguinal
- Femoral
- Umbilical
- Incisional
Hernias arise due to weakness in the containing cavity
Give 3 examples
- Congenitally related
- Post surgery where wounds have not healed properly (Incisional hernia)
- Normal points of weakness
What is the inguinal canal?
An oblique passage through the lower part of the abdominal wall
What structures go through the Inguinal Canal in males and females
Males: Structures pass through from Abdomen to Testis/ Scrotum
Females: Round Ligament passes from Uterus to Labium Majus
Which gender are Inguinal hernias more common in?
Which body side gets more inguinal hernias
Male
Right
The Inguinal Ligament extends from ASIS to Pubic Tubercle.
Where is the Deep Inguinal Ring found along here?
How does it continue to its opening
At midpoint of Inguinal ligament
Continues Infero-obliquely, opening at Superficial Inguinal Ring
What forms the Floor and Roof of Inguinal Canal
Floor: Thickening of External Olique called the Inguinal Ligament
Roof: Internal Oblique and Transversus Abdominis combine to form the Conjoint Tendon
What does the Conjoint tendon insert into?
Pubic bone (posterior aspect)
What are the Anterior and Posterior walls of the Inguinal Canal formed by?
Anterior: External Oblique (before it rolls up to form inguinal ligament)
Posterior: Transversalis Fascia (This lies posterior to the muscles forming the Roof)
What is the Lacunar Ligament?
The triangular shaped connection between Inguinal Ligament (anteriorly) and Pectineal Ligament (posteriorly)
Briefly describe how the testis descend, in combination with the development of the Processus Vaginalis
- Initially retroperitoneal, connected to Gubernaculum
- The Processus Vaginalis is the antero-inferior point of the developing peritoneum
- Gubernaculum shortens and pulls testis infero-anteriorly through Inguinal Canal so that it meets the the Processus Vaginalis at the scrotum
- Processus Vaginalis obliterates leaving Tunica Vaginalis around Testis, which is anchored by the Scrotal Ligament (remnant of Gubernaculum)
If the Processus Vaginalis doesn’t obliterate OR obliterates abnormally, what could happen?
Left with open channel between scrotum and peritoneal cavity, where;
- Fluid can collect (Hyrdocoele)
- Hernias can descend into scrotum
Compare the occurrence of the 2 types of Inguinal Hernias (75% of all hernias)
Direct: 25%
Indirect: 50%, Mainly right sided, Male: Female ratio of 7:1
What percentage of all hernias are;
- Umbilical
- Femoral
- Incisional
Umbilical: 10%
Femoral: 3-5%
Incisional: 10%
Describe the anatomy of an Indirect Inguinal Hernia
- Enters Inguinal Canal via Deep Inguinal Ring
- Herniates it varying length depending on whee Processus Vaginalis obliterates
- Lies lateral to Inferior Epigastric Vessels (We consider the point where it leaves the abdominal cavity, that is the Deep Ring which is lateral to the vessels)
(E.g no PV obliteration=hernia descends into scrotum)
Describe the anatomy of an Direct Inguinal Hernia
- Bulges through a weakness in abdominal wall called Hesselbach’s Triangle
- Potentially in vicinity of Superifical Inguinal Ring
- Medial to Inferior Epigastric Vessels
State the 3 borders of Hesselbach’s Triangle
Medial: Rectus Abdominis (lateral margin)
Supero-lateral: Inferior Epigastric Vessels
Inferior: Inguinal Ligament
Can Direct Inguinal Hernias push forward and end up as a scrotal hernia
Yes, depending on level of defect of Hesselbach’s Triangle
Who are Femoral Hernias more common in?
Why?
Females, as Femoral Ring (entrance to femoral canal) is slightly wider (due to anatomy differences related to childbirth)
Are inguinal hernias or femoral hernias more common in females?
Inguinal
Where might you feel a lump in a femoral hernia?
At Saphenous opening, inferior to Inguinal Ligament
What structures are immediately lateral to femoral ring
Lateral: Femoral vein (artery is lateral to vein, NAVEL)
Medial: Lacunar Ligament
Why are femoral hernias uncommon?
What could happen in a femoral hernia?
Femoral ring is quite small, so hernia can easily get Incarcerated and Strangulated (Can lead to tissue break down and necrosis)
Describe the Incidence of Umbilical Hernias, most of which resolve spontaneously
(Common in infants)
- Equal in males and females
- Higher incidence in;
- Premature births
- Those of African Descent
- Low Birthweight
Describe the anatomy of an Umbilical Hernia
What else can pass through?
Hernia through Umbilical Ring (Defect in Linea Alba), which normally closes
Umbilical cord
When does the Umbilical Ring normally close?
By age of 3-4 years
Describe the usual presentation of an Umbilical Hernia
How do we treat if it does become a problem?
- Not usually painful
- Unusual to be Incarcerated or Strangulated
Surgery
What do we call an Umbilical hernia in adults?
Who is it more common in?
What is 1 risk factor?
What could happen?
Para-umbilical hernia
- Females
- Obesity
- Risk of strangulation (as defect is small)
What is an Incisional Hernia?
What are 4 risk factors
Hernia coming through a previous incision (such as from surgery)
- Obesity
- In Midline
- Wound infection
- Emergency surgery (as opposed to a planned surgeryI
Most Incisional hernias remain asymptomatic
How many end up Incarcerated or Strangulated
Incarcerated: 6-15%
Strangulated: 2%
What are 5 common abdominal incisions
- Midline incision through Linea Alba (Avascular, can be extended, quite painful post-op)
- Paramedian either side of Linea Alba, rarely used (Poor cosmetic outcome, can damage nerves/ structures)
- Gridiron, for open Appendicectomy (at McBurney’s point, 2/3 of distance from Umbilicus to ASIS)
- Pfannenstial to access uterus and urological structures (Curvy incision above a longitudinal one in Linea Alba)
- Kocher, to access Liver/ Biliary tract, for Cholecystectomies which are now mostly down laparoscopically (Parallel to subcostal margin)
