Internal hernia

Last updated: August 6, 2021

Summarytoggle arrow icon

An internal hernia is the protrusion of visceral contents through a congenital or acquired defect in the peritoneum or mesentery within the abdominal cavity. Internal hernias have an incidence of < 1% and are significantly less common than external hernias. Patients with a history of Roux-en-Y gastric bypass or liver transplant are especially at risk of internal hernia formation. Small bowel loops are the most common content of an internal hernia. For this reason, the typical clinical presentation is that of a mechanical small bowel obstruction (i.e., colicky abdominal pain, vomiting, constipation, abdominal distention). Contrast-enhanced CT scan is the imaging modality of choice in most cases, but surgical intervention is often required for definitive diagnosis and treatment. Incarceration or strangulation of internal hernias carries a high mortality rate; rapid diagnosis and surgical repair is therefore imperative.


Epidemiological data refers to the US, unless otherwise specified.

Internal hernias are a protrusion of visceral contents through a defect in the peritoneum or the mesentery :


Internal hernias may be classified as congenital or acquired, or by location as follows:


The diagnosis of an internal hernia is confirmed by laparoscopy in the majority of cases.

If an internal hernia leads to incarceration, the mortality rate is ∼ 80%.


  1. Yeo CJ, Matthews JB, McFadden DW, Pemberton JH, Peters JH . Shackelford's Surgery of the Alimentary Tract. Elsevier Saunders ; 2012
  2. Martin LC, Merkle EM, Thompson WM. Review of internal hernias: radiographic and clinical findings. AJR Am J Roentgenol. 2006; 186 (3): p.703-717. doi: 10.2214/AJR.05.0644 . | Open in Read by QxMD

3 free articles remaining

You have 3 free member-only articles left this month. Sign up and get unlimited access.
 Evidence-based content, created and peer-reviewed by physicians. Read the disclaimer