Internal hernia

An overview of internal hernias, their types, causes, and clinical significance

Overview

An internal hernia is a condition where an internal organ, typically a part of the intestine, protrudes through a defect within the peritoneal cavity. Unlike external hernias, internal hernias occur within the confines of the abdominal cavity and are not visible externally. They can lead to serious complications such as intestinal obstruction and ischemia.

Diagram illustrating an internal hernia

Types of Internal Hernias

Internal hernias can be classified based on their location and the structures involved. The main types include:

Paraduodenal Hernia

Paraduodenal hernias are the most common type of internal hernia. They occur when the small intestine herniates through a defect near the duodenum. These hernias are further divided into left and right paraduodenal hernias, depending on their location relative to the duodenum.

Foramen of Winslow Hernia

This type of hernia occurs when abdominal contents herniate through the foramen of Winslow, an opening that connects the lesser sac to the greater sac of the peritoneal cavity.

Transmesenteric Hernia

Transmesenteric hernias occur when the intestine herniates through a defect in the mesentery, the tissue that attaches the intestines to the posterior abdominal wall.

Pericecal Hernia

Pericecal hernias involve the herniation of intestinal loops around the cecum, the beginning of the large intestine.

Sigmoid Mesocolon Hernia

This type involves herniation through defects in the sigmoid mesocolon, the mesentery associated with the sigmoid colon.

Causes

Internal hernias can be congenital or acquired. Congenital internal hernias are due to developmental anomalies, such as abnormal rotation of the midgut during fetal development. Acquired internal hernias may result from surgical procedures, trauma, or inflammation that creates defects or spaces within the peritoneal cavity.

Clinical Presentation

Patients with internal hernias may present with symptoms of abdominal pain, nausea, vomiting, and signs of bowel obstruction. The symptoms can be intermittent and vary in severity, making diagnosis challenging. Imaging studies, such as CT scans, are often used to identify internal hernias.

Treatment

The treatment of internal hernias typically involves surgical intervention to reduce the hernia and repair the defect. In cases of bowel ischemia, resection of the affected bowel segment may be necessary.

Related pages

• Hernia
• Intestinal obstruction
• Abdominal cavity