6.2 Hernias Flashcards
What are the 3 lateral abdominal wall muscles?
What 2 muscles lies down the midline, and what is their relationship with the lateral wall muscles?
External Oblique
Internal oblique
Transversus Abdominus
2 Rectus Abdominus muscles lie down the middle of the abdomen (lifting muscles) and are enclosed by the aponeurosis of the lateral abdominal wall muscles EXCEPT in the lower portion of the abdomen where below the arcuate line there is no posterior sheath
Define a Hernia
A hernia is an abnormal protrusion of a cavity’s contents through a weakness in the wall of the cavity, taking with it the linings of that cavity.
What is the relationship between hernias and protrusions?
A hernia is a protusion; not all protusions are hernias
List and briefly describe 4 common Hernias in the abdomen
Inguinal hernias - these are very common.
Umbilical hernia’s - these only occur ONLY in babies
Para-umbilical hernias - these occur in adults
Epigastric hernias - occur in the midline down the linea alba
What is the line in the middle of the abdomen called?
What are the lines either side of the rectus abdominus muscles called?
In the middle we have the linea alba
Either side of the rectus abdominus muscles we have the linea semilunaris
What is the difference between a direct vs indirect hernia?
Direct Hernias: Occur within the “weak area” within Hesselbach’s triangle (usually acquired muscle weakness)
Indirect Hernias: occur at the deep inguinal ring (usually a congenital weakness)
Give 7 causes why someone may be at an increased risk of Hernias?
1) Design weakness ➞ eg. the myopectinate orifices (area of inguinal canal)
2) Entry/Exit of structures through the abdominal wall causes weakness.
3) Developmental failures ➞ failure of processes vaginalis to obliterate following decent of testis
4) Collagen disease
5) Increasing age ➞ due to weaking of the abdominal wall.
6) Pregnancy ➞ hormones make ligaments slack + enlarging uterus. These cause abdominal wall to stretch, which can lead to the umbilical or inguinal hernia.
7) Smoking ➞ destroys CT in the body
Give 4 examples of structures entering/exiting the abdominal wall that may lead to Hernias
1) Spermatic cord passing through the deep inguinal ring
2) Femoral vessels passing under the inguinal ligament into the leg
3) Oesophagus passing through the oesophageal hiatus in the diaphragm
4) Obturator nerve passing through the obturator foramen
What 2 structures does the Inguinal ligament run between?
What is the midpoint called?
What can be found at the mid-inguinal point?
The inguinal ligament runs from the ASIS to the pubic tubercle.
The midpoint is the “mid-point inguinal”
The femoral artery can be found at the mid-inguinal point
What is the myo-pectineal orifice? What type of hernias can this lead to?
a weak area in the groin ➞ can leads to the formation of direct and indirect hernias.
What are the boarders of Hesselbach’s Triangle?
Why is this area prone to Hernias?
Boarders:
Medial – lateral border of the rectus abdominis muscle
Lateral – inferior epigastric vessels
Inferior – inguinal ligament
There is no strong tissue in this area ➞ prone to Hernias
What is the main causes of a Femoral Hernia?
Compare a femoral hernia to an inguinal hernia (how common, strangulation, treatment)
List one problem it can lead to
Femoral hernias are caused by the inflexibility of the lacunar ligament (F>M)
Less common than an inguinal hernia but more likely to strangulate. Inguinal Hernias can be treated laparoscopically, femoral MUST have surgery
Can cause bowel obstruction
How do we examine a patient with a groin hernia?
Stand patient up, palpate groin area and ask them to cough ➞ this should reveal the hernia (can be felt)
However, if hernia still cannot be felt because it is too small, an invagination test can be performed
Invagination test: invaginate scrotum and place ring finger into the inguinal canal (can be very painful). Ask patient to cough again and If the hernia is small you should feel the cough impulse at the deep ring
During he invagination test why should a small hernia be felt at the deep inguinal ring?
Because this is where the Hernia will start before it enlarges down the inguinal canal and into the scrotum
List 3 generic causes of lumps around the groin area
1) Lymph node
2) Lipoma
3) Sebaceous cyst
List 6 specific causes of lumps around the groin area
1) Inguinal Hernia (direct or Indirect)
2) Femoral Hernia
3) Sapheno-varix
4) Hydrocoele of the cord
5) Ectopic Testis
6) Psoas Abscess
What is a Sapheno-varix?
What is Hydrocoele of the cord + the female equivalent
Where can Ectopic testis be found?
What is a Psoas Abscess
Saphennous-varix ➞ venous aneurysm at the junction where the great saphennous vein descends through the cribriform fascia and joins the deep saphenous vein
Hydrocoele of the cord ➞ If the process vaginalis partially obliterates below and above it, leaving fluid between it (in females ➞ hydrocoele of the canal of nuck)
Ectopic testis - can be found anywhere along the path of decent
Psoas Abscess - abscess from TB of the spine that drains down the illipsoas muscle and appears in the groin
List the 5 types of hernia based on complexity and what each is
Occult - small hernias that cannot be seen
Reducible - a hernia with a bulge that flattens out when you lie down or push against it gently
Irreducible (incarceration)- herniated tissue becomes trapped and cannot easily be moved back into place
Strangulation - hernia that has had its venous blood supply cut off
Infarcted - can be caused strangulation and venous gangrene
Which type of hernia can give you strangulation without bowel obstruction?
Richter’s Hernia
What causes a Richter’s Hernia?
Why does this give you strangulation without obstruction?
Occurs when the antimesenteric wall of the intestine protrudes through a defect in the abdominal wall
Can result in strangulation and necrosis without intestinal obstruction
What causes a sliding hernia?
What can therefore be said about its locations
This is a form of diaphragmatic hernia when a retroperitoneal structure “slides” down the posterior abdominal wall and herniates directly or indirectly into the inguinal canal, dragging overlying peritoneum with it.
Thus, sliding hernias lie behind and outside the peritoneal sac.
List 2 GI tract structures that can be involved in a sliding hernia and why?
1) Sigmoid sliding hernia
2) Caecum and Apendix sliding hernia
because these are both retroperitoneal structures
What is a Pantaloon hernia?
This is a combined Direct and Indirect Hernia with the Inferior Epigastric vessels located between it
What is an Umbilical hernia?
Occurs in children and newborns at the site of the umbilical cord. They often close spontaneously but surgery may be required if there is a danger of strangulation or has not self-resolved before school
What is a Para-umbilical hernia? Who does it commonly affect?
Occurs in adults due to weakening of the tissues around the umbilicus.
Occurs through the Linea alba above or below umbilicus and in common in obese and multiparous women
Where do Spigelian Hernias occur?
Occurs at the junction between the linea semilunaris and the arcuate line
What is an Incisional Herniae?
An Incisional Hernia occurs through a previously made incision in the abdominal wall due to the scar left from a previous surgical operation
Often because collagen fibres haven’t healed correctly
Incisional hernias are normally very large and often cause obstruction but NOT strangulation
Give some predisposing factor to an Incisional Herniae
Patient factors:
- obesity
- malnutrition
- Immunosuppression
- Steroids
- chronic cough
- Cancer
Wound Factors:
- Poor tissue
- Wound infection
Surgical factors:
- Suture material
- Suturing technique
What is Divarication of Recti? (Diastasis)
A bulge cause above the Linea Alba
No danger of obstruction or Strangulation ➞ it is caused when the muscles come apart (often unfit people, or in pregnancy)
Treatment Only for Cosmesis
What is a Para-Stomal Herniae? What is a major cause?
Commonly caused by Colostomy’s because the sides of the incision are very weak meaning parts of the bowl can get stuck.
It can obstruct and strangulate
A Para-stomach hernia can cause the stoma bag to not fit correctly which can result in major leakage
What is a Lumbar Hernia?
It is a very rare external herniae ➞ defect in the postero-lateral abdominal wall (defect in the triangle of petit)
What is a Obturator Hernia?
Obturator hernia comes through the obturator canal.
Can cause pain as the obturator nerve comes through this area also
Commonly presents with leg pain and bowel obstruction
What are 2 main treatments for hernias
1) operative: open (general or local anaesthetic) laparoscopic (TAPP or TEPP)
2) non-operative: Truss, no Treatment
What are the 2 types of laparoscopic repair?
TAPP - transabdominal preperitoneal
TEPP - totally extraperitoneal repair
What are the 4 main principals of hernia repair?
1) Try and obtain primary closure of muscle layer
2) Tension free
3) Laparoscopic reinforcement
4) Use of specialised meshes
Give 2 causes of groin pain without a hernia?
1) Post-operative hernia repair
2) Sportsman’s groin
What causes post-operative groin pain?
Nerve entrapment (main cause) Stitch Mesh Scar tissue (can shrink and cause nerve to be pulled against)
What are the 3 nerves found in the groin area that are at risk of damage in surgery?
1) Illioinguinal nerve - supplies a area of skin in the inner aspect of the thigh
2) Genitofemoral nerve
3) Illiohypogastric
What causes Sportsman’s Groin?
Give 4 specific examples
Caused by tears in the muscles or joints
examples:
1) Torn external oblique aponeurosis
2) Conjoint tendon tear
3) Tear in the transversalis fascia
4) Entrapment of the ilioinguinal or genitofemoral nerve
