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Abdominal hernias



Gastrointestinal system


Peritoneum and peritoneal cavity
Upper gastrointestinal tract disorders
Lower gastrointestinal tract disorders
Liver, gallbladder and pancreas disorders
Gastrointestinal system pathology review

Abdominal hernias


0 / 4 complete

USMLE® Step 1 style questions USMLE

4 questions

USMLE® Step 2 style questions USMLE

4 questions

A 64-year-old man comes to the office for the evaluation of a mass on the right side of his groin. The patient first noted the mass after helping his daughter move to a new home. He reports sharp discomfort in the right groin worsens with walking and heavy lifting. Resting supine decreases the severity of the pain. Past medical history is significant for type 2 diabetes mellitus. Current medications include atorvastatin and metformin. BMI is 37 kg/m2. Vitals are within normal limits. Physical examination shows a bulge in the right groin above the inguinal ligament which increases in size when the patient coughs. There is no overlying erythema or warmth. The patient is referred to a surgeon and scheduled for a laparoscopic repair.

Which of the following landmarks will help the surgeon to differentiate a direct versus an indirect inguinal hernia?


Content Reviewers:

Viviana Popa, MD, Arjun Maini

Abdominal hernias, also called external hernias, are when an abdominal organ, or part of an abdominal organ protrudes through the abdominal wall, usually at a site of weakness. They can be classified into midline hernias and groin hernias. Most frequent types of midline hernias are the epigastric and umbilical hernias, while groin hernias can further be classified into inguinal and femoral hernias. There’s also incisional hernias, which is when contents herniate through an incisional scar from a previous abdominal surgery

Now, the abdominal wall is made up of a few layers. The deepest layer is the visceral peritoneum, which covers many of the abdominal organs and lines the peritoneal space. That layer wraps around to form the parietal peritoneum. Then, moving externally, there is the extraperitoneal fat, the transversalis fascia, the muscle layer with the internal and external oblique and transversus abdominis aponeurosis and a layer of fascia which has different names in different regions. Ok, so anything that increases the pressure of the abdominal cavity may result in a sac that forms in the abdominal wall through which organs might protrude.

When organs protrude through the midline, that results in a midline hernia. Midline hernias include the epigastric hernia, which is when abdominal organs herniate through the linea alba, or the part of the midline between the xiphoid process and the umbilicus. With umbilical hernias, on the other hand, the organ protrudes through the umbilicus.

And then there’s groin hernias, which can be classified into inguinal hernias, the more common type, and femoral hernias.

With inguinal hernias, the contents of the abdominal cavity, usually fat or part of the small intestine, protrude through the inguinal canal.

The inguinal canal lies between the muscles of the anterior abdominal wall. The canal is bound superiorly by the internal oblique and transversus abdominis muscles, anteriorly by the external and internal oblique aponeurosis, inferiorly by the inguinal ligament, and posteriorly by the transversalis fascia and conjoint tendon.

Finally, the inguinal canal also has two openings: an internal one, called the deep inguinal ring, which is an orifice of the transversalis muscle fascia, located lateral to the inferior epigastric vessels, and an external one, called the superficial inguinal ring, which is an opening in the external oblique muscle aponeurosis.

Now, remember that the inguinal canal forms during embryological development. The process begins when a projection of peritoneum called the processus vaginalis herniates through the abdominal body wall, to allow the gonads, testes in males, and ovaries in females, to descend from the abdomen, where they formed, to their final location in the scrotum, or pelvis, respectively. When the gonads have descended completely, the processus vaginalis is obliterated, closing off the tunnel. But even though both males and females have inguinal canals, since the testes have a longer journey ahead, this makes the inguinal canals larger and more prominent in males, creating a physiological site of weakness in the abdominal wall. This makes inguinal hernias far more common in genetically male individuals, so we’re going to be referring to this population moving forward.


A hernia is a protrusion of an organ or part of it through a weakened area in the wall that normally holds it in place. Abdominal wall hernias are a protrusion of the abdominal content through a defect in the abdominal wall. There exist various types of abdominal wall hernia, but ventral hernias are more common than other types and occur when the intestine, bladder, or other abdominal organs push through the abdomen wall.

Symptoms may include pain, swelling, and a feeling of weakness or pressure in the abdomen, with some of the rare but serious complications being incarceration or strangulation of an organ, mostly the bowels. A doctor can usually diagnose a hernia by examining the area and may order additional tests if needed. Abdominal wall hernias are generally treated with surgical repair of the defect.

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