What Is an Internal Hernia?

An internal hernia occurs when a part of the intestine protrudes through an opening or defect within the abdominal cavity, rather than through the abdominal wall. This condition can cause intestinal obstruction and may lead to life-threatening complications if not diagnosed and treated promptly.

Unlike external hernias, internal hernias are not visible from the outside.

What Causes an Internal Hernia?

Internal hernias may be congenital (present at birth) or acquired due to other conditions or surgeries. Common causes include:

• Congenital defects in the mesentery (tissue that holds intestines in place)
• Previous abdominal surgeries, especially those involving bowel reconstruction or bypass
• Trauma causing internal tears or holes
• Inflammatory bowel disease (e.g., Crohn’s disease)
• Weight loss surgery, such as Roux-en-Y gastric bypass, which increases risk of internal herniation

What Are the Symptoms of an Internal Hernia?

Symptoms can vary and may come and go, but common signs include:

• Severe abdominal pain (sudden or cramping)
• Nausea and vomiting
• Abdominal bloating or distension
• Constipation or inability to pass gas
• Intermittent episodes of pain, especially after eating
• Signs of bowel obstruction, such as no bowel movements

If blood supply is cut off to the intestine (strangulation), symptoms may worsen rapidly and become a surgical emergency.

How Is an Internal Hernia Diagnosed?

Because symptoms mimic other gastrointestinal issues and there’s no external bulge, diagnosis can be challenging. The following tools may help:

• CT scan of the abdomen and pelvis – the most effective tool for detection
• X-rays (to check for obstruction)
• Diagnostic laparoscopy – direct visualization inside the abdomen
• Review of surgical history – especially important in patients with previous abdominal procedures

Early imaging is key for diagnosis, especially in post-surgical patients with new abdominal pain.

How Is an Internal Hernia Treated?

Emergency Treatment:

• Surgical intervention is often required to:
  • Reduce the herniated bowel
  • Repair or close the internal opening
  • Resect any necrotic (dead) bowel if strangulation has occurred

Supportive Care:

• IV fluids and bowel rest may be given while preparing for surgery
• Pain management and monitoring are provided in stable cases

Delaying treatment can lead to bowel ischemia or perforation, which can be life-threatening.

Is an Internal Hernia Dangerous?

Yes. Internal hernias can cause bowel obstruction, strangulation, and tissue death. If untreated, these can result in:

• Sepsis
• Permanent intestinal damage
• Death

That’s why timely diagnosis and surgical treatment are essential.

Can Internal Hernias Be Prevented?

Not all cases can be prevented, especially congenital ones. However, some steps can reduce the risk:

• Careful surgical techniques to avoid leaving openings inside the abdomen
• Monitoring after weight loss or bowel surgery for symptoms of obstruction
• Early evaluation of unexplained abdominal pain in patients with prior surgeries