[25] Other Hernias Flashcards
What is a hernia defined as?
The protrusion of part or a whole of an organ or tissue through the wall of the cavity that normally contains it
Where does an epigastric hernia occur?
In the midline through the fibres of the linea alba
How common are epigastric hernias?
Relatively common, with a prevalence of up to 10%
Who do epigastric hernias most commonly affect?
Middle-aged men
How do epigastric hernias present?
They are typically asymptomatic, but may present as a midline mass that disappears when lying on the back
What is an important differential for epigastric hernias?
Divarication of the recti
What is divarication of the recti?
A cosmetic condition where the linea alba becomes widened, resulting in a palpably increased distance between the rectus muscles and a subsequent midline buldge
Where does a paraumbilical hernia occur?
Through the linea alba around the umbilicus (not through the umbilicus itself)
What are paraumbilical hernias typically secondary too?
Chronic raised intra-abdominal pressure, such as with obesity, pregnancy, or ascites
How do paraumbilical hernias present?
As a painful lump around the umbilicus, which will worsen with an increased intra-abdominal pressure such as straining or coughing
What can umbilical hernias form as in infants?
Ventral wall abnormalities
Give two examples of ventral wall abnormalities in infants
Omphalocele
Gastroschisis
What is a spigelian hernia?
A rare form of abdominal hernia that occurs at the semilunar line around the level of the arcuate line
What is the rectus abdominis muscle enclosed by?
The rectus sheath
Where is the arcuate line?
At the lower limit of the posterior layer of the rectus sheath (about 1/3 of the distance between the umbilicus and pubic symphysis)
What is the semilunar line?
The tendinous lateral border of the rectus, where the aponeuroses fuse
How do spigelian hernias present?
As a small tender mass at the lower lateral edge of the rectus abdominus
Why should spigelian hernias be repaired?
Due to the high risk of strangulation
What % of cases of spigelian hernias in male infants have cryptorchidism also present?
75%
What is cryptochidism and spigelian hernias in male infants likely associated with?
Failure in gubernaculum development
What is an obturator hernia?
A hernia of the pelvic floor, occurring at the obturator foramen, into the obturator canal
Who are obturator hernias more common in?
Women
Middle-aged patients
Why are obturator hernias more common in women?
Due to wide pelvis
What side do obturator hernias typically occur on?
Right side
What do obturator hernias often present following?
A period of rapid weight loss
Why do obturator hernias often present following a period of rapid weight loss?
Due to the substantial amount of fat that is contained within the obturator canal, as loosing this fat results in a larger space for potential herniation to develop
How are obturator hernias often diagnosed?
Intra-operatively, in patients presenting with bowel obstruction
How do patients with obturator hernias classically present?
With a mass in the upper medial thigh
Howship-Romberg side
What % of patients with Howship-Romberg side present with Howship-Romberg sign?
Around 50%
What is Howship-Rombergs sign?
Hip and knee pain exacerbated by thigh extension, medial rotation, and abduction
What causes Howship-Rombergs sign in obturator hernias?
Compression of the obturator nerve passing through the obturator canal
Where is the obturator canal formed?
In the obturator foramen
What is the obturator foramen?
A large opening between the ischium and the pubis bones
What is the obturator canal formed by?
The gap through the obturator membrane
Where does the obturator canal pass?
Into the medial thigh
What does the obturator canal contain?
Obturator nerve
Obturator artery
Obturator vein
What is a Littre’s hernia?
A very rare form of abdominal hernia, whereby there is herniation of Meckel’s diverticulum
Where does a Littre’s hernia most commonly occur?
At the inguinal canal
Is there a high risk of strangulation with Littre’s hernias?
Yes
What is a lumbar hernia?
A rare posterior hernia
What causes lumbar hernias?
They can occur spontaneously through an area of weakness, or iatrogenically following surgery
How do lumbar hernias present?
As a posterior mass with associated back pain
Where are the common areas of physiological weakness in the lumbar posterior wall that lumbar hernias most often occur?
Superior lumbar triangle
Inferior lumbar triangle
What is true of most lumbar hernias?
They are incisional
What surgery to lumbar hernias classically follow?
Renal surgery
What is a Richter’s hernia?
A partial herniation of small bowel, whereby only the anti-mesenteric border becomes strangulated, and therefore only part of the lumen is within the hernia
How will a Richter’s hernia present?
As a tender, irreducible mass at the herniating oriface, with varying levels of obstruction
What is the level of obstruction caused by a Richter’s hernia dependant on?
How much of the bowel circumference is involved
Why are Richter’s hernias often surgical emergencies?
Due to obstruction
What care must be taken during surgery to repair a Richter’s hernia?
To identify the hernia, so as not to damage the bowel during surgery
