1. Ali Jassim Alhashli, BSc www.alhashli.com
Kingdom of Bahrain Arabian Gulf University College of Medicine and Medical Sciences
GI System – Review
Problem (7) – Hernia
Ali Jassim Alhashli, BSc

2. Definition: protrusion of a viscus through an abnormal defect in the wall of the cavity in which it is contained.
Epidemiology of hernia:
The most common hernia in males and females is indirect inguinal hernia.
Hernias:
Indirect = 50%.
Direct = 25%.
Femoral = 5%.
Classification of hernias:
Internal hernias: in which the sac is within the visceral cavity. Examples: diaphragmatic hernia and brainstem herniation.
External hernias: in which the sac protrudes through the abdominal wall. Examples: direct (medial to inferior epigastric vessels), indirect (lateral to inferior epigastric vessels-in inguinal canal) and umbilical.
Reducable hernias: can be returned to the abdomen.
Irreducable (incarcerated) hernias: cannot be returned to the abdomen.
Strangulated: ischemia of the viscus (surgical emergency!).
What are the causes of hernia?
Congenital: patent processus vaginalis, prematurity or collagen vascular disease (such as Ehlers-Danlos syndrome).
Acquired: weakness of abdominal wall, surgery, trauma, pregnancy, ascites, obesity, lifting heavy objects, chronic constipation and chronic cough (patients with COPD).
Anatomy

3. Anatomy Mention the layers of abdominal wall in order?
Skin, subcutaneous fat, Scarpa’s fascia, external oblique muscle, internal oblique muscle, tansversus abdominis muscle, transversalis fascia, peritoneal fat, parietal peritoneum.
What is the inguinal canal?
It is a 4 cm canal which is extending from internal (deep) ring to external (superficial) ring.
Boundaries:
Anterior:
Medial 2/3: external oblique aponeurosis.
Lateral 1/3: internal oblique muscle.
Posterior:
Medially: conjoint tendon.
Laterally: transversalis fascia.
Roof: arching fibers of internal oblique and transversus abdominis.
Floor: inguinal ligament.
Contents:
Males: spermatic cord and ilioinguinal nerve.
Females: round ligament of uterus and ilioinguinal nerve.
Mention the contents of the spermatic cord (rule of 3’s):
3 structures:
Vas deferens.
Lymphatics.
Pampiniform plexus.
3 arteries:
Testicular artery.
Cremasteric artery.
Artery to vas deferens.
3 nerves:
Genital branch of genitofemoral nerve.
Cremasteric nerve.
Sympathetic nerve fibers.
Anatomy

4. Anatomy

5. Anatomy

6. Anatomy
What are the contents of femoral canal (remember: NAVEL… lateral to medial):
Nerve, Artery, Vein, Empty space (femoral canal) and Lymph nodes.
Define Hasselbach’s triangle and its boundaries (site of direct abdominal hernia):
Medially: rectus abdominis muscle.
Laterally: inferior epigastric vessels.
Inferiorly: inguinal ligament.

7. Epidemiology: it is more common among males and causes 15-20% of intestinal obstruction.
What are the risk factors (as mentioned earlier)?
Congenital: mostly due to patent processus vaginalis.
Acquired: weakness of abdominal wall muscles (aging), increased intra-abdominal pressure (chronic constipation and chronic coughing), pregnancy, ascites, peritoneal dialysis.
Why do females have increased predisposition for femoral hernias?
Because of increased diameter of true pelvis. Therefore, they have wider femoral canal.
Signs and symptoms:
Patients are usually asymptomatic but sometimes they might complain of non-specific discomfort.
They have a bulge in the groin which usually becomes more prominent with increased intra-abdominal pressure.
Diagnosis (MAINLY BY PHYSICAL EXAMINATION):
Let your patient stand and ask him to cough. The hernia will bulge and become prominent. If you want to differentiate it from hydrocele transilluminate it (light will not pass through it).
What are your differential diagnoses of hernia?
Enlarged lymph node.
Lymphoma.
Lipoma.
Hematoma.
Psoas abscess.
Femoral artery aneurysm.
Undescended or ectopic testes.
Varicocele or hematocele.
Management: TENSION-FREE REPAIR (Lichtenstein procedure):
For support you might use: fascia, aponeurosis or mesh.
Herniotomy: hernia sac is identified, neck ligated and the sack is reduced.
Hernirrhaphy and hernioplasty is repair of posterior wall of inguinal canal and the internal (deep) ring.
Inguinal Hernia

8. Classification of Inguinal Hernias
Direct inguinal hernia:
Definition: hernia which enters the inguinal canal through a weakened posterior wall. IT NEVER PASSES THROUGH INTERNAL (DEEP) RING.
Features:
Exclusively in old males.
Never reaches the scrotum.
Travels behind the spermatic cord.
Can lead to damage of ilioinguinal nerve.
In Hasselbach’s triangle (medial to inferior epigastric vessels).
Indirect inguinal hernia:
Definition: hernia which enters the inguinal canal through the internal (deep) ring and exits through the external (superficial) ring thus reaching the scrotum.
It is the most common type of inguinal hernias in both males and females but it is more common among males.
It is lateral to inferior epigastric vessels.
Early in life, it is more common to occur on the right side due to late descend of right testicle.
It is bilateral in 1/3 of cases!

9. Classification of Inguinal Hernias

10. Femoral Hernia
Definition: it is a form of indirect hernia in which a viscus protrudes in the femoral canal that is located medially to femoral vessels below the inguinal ligament.
Femoral canal is 1.25 cm in length, extending from femoral ring to saphenous opening. Boundaries:
Anterior: inguinal ligament.
Posterior: Cooper’s ligament.
Lateral: femoral vein.
Medial: lacunar ligament.
Features:
Femoral hernia is uncommon (15% of all hernias), but if it occurs it is more common among females especially elderly.
More common to occur on the right side.
22% strangulate after 3 months; 45% strangulate after 21 months.
Symptoms:
Bulge under the inguinal ligament.
Dull, dragging pain in the groin.
If obstructed: vomiting and constipation.
If strangulated: severe pain and shock.

11. Femoral Hernia

12. Umbilical Hernia Acquired umbilical hernia:
Abdominal contents herniate through a defect in the umbilicus. This is more common to occur among females.
Causes (generally: abdominal distention):
Repeated pregnancies.
Ascites.
Obesity.
Complications:
Common: strangulation of colon and omentum. Omentum is a layer of peritoneum which surrounds abdominal organs (there is greater and lesser omentum).
There is a risk of umbilical hernia to rupture in those patients with chronic ascites due to cirrhosis.
Treatment:
> 2 cm defect: closed by loosely placed polypropylene suture.
< 2 cm defect: prosthetic repair (using a mesh for example).
Pediatric umbilical hernia:
Cause: failure of timely closure of umbilical ring which leaves a central defect in linea alba (a fibrous structure which runs down the midline of the abdomen).
Management:
It usually resolves spontaneously within 4 years especially if the defect is > 2 cm.
Indications of surgery:
Age < 4 years.
Defect < 2 cm.
Hernia is disfiguring.
Umbilical Hernia