EM@3AM: Hernia

Author: Brit Long, MD (@long_brit, EM Attending Physician, San Antonio, TX) // Edited by: Alex Koyfman, MD (@EMHighAK, EM Attending Physician, UTSW / Parkland Memorial Hospital)

Welcome to EM@3AM, an emDOCs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

A 61-year-old male presents with lower abdominal pain on the right side. He says “I’ve had this bulge in my groin on the right for two days”. He denies any prior episodes of this, fever, nausea/vomiting, or other pain. He has not noted any redness over the site, and upon closer questioning, he thinks the mass has been intermittently present.

Triage vital signs (VS): BP 148/71, HR 89, T 98.9 Oral, RR 18, SpO2 97% on RA.

Physical exam reveals a patient who appears nontoxic. You find a small bulge in the right groin, but with no redness or discoloration of the skin. Palpation reveals mild tenderness over the site.

What’s the next step in your evaluation and treatment?

AnswerInguinal hernia, not strangulated

  • Background: Close to 10% of the population develops a hernia over their lifetime, and hernias are a common need for surgery. Classification is based on location, contents of the hernia, and hernia status (see below).
    • Forms include reducible, incarcerated, strangulated.
    • Reducible: hernia sac is soft and easy to replace through the defect.
    • Incarcerated: hernia is firm, painful, and nonreducible through direct pressure.
    • Strangulated: refers to an incarcerated hernia with impaired blood flow. Pain is typically severe, with redness over the site and evidence of obstruction.
  • Types:
    • Inguinal: Most common (66-75%) form of hernia. Presents as a mass in the groin. Male predilection, though this is the most common form overall in men and women.
      • Indirect hernia is a hernia that passes from inguinal ring into the scrotum (50-66%).
      • Direct hernia is a hernia that passes through the trasversalis fascia into Hesselbach’s triangle (25%).
    • Femoral: More common in females (10 female:1 male), with hernia sac protruding through femoral canal below inguinal ring. This hernia is prone to complications (40%).
    • Obturator: Hernia sac with bowel that herniates through obturator canal; almost always presents as partial or complete obstruction. High complication rate. Classic presentation is an elderly female patient with signs of bowel obstruction.
    • Internal: Protrusion of internal organ into a retroperitoneal fossa/foramen in the abdominal cavity. High risk for incarceration and strangulation, along with obstruction. Predisposing conditions include prior gastric bypass or other abdominal injuries (GSW).
    • Richter: Involves antimesenteric intestine border and portion of wall. Often presents with no vomiting or evidence of obstruction, creating difficulty with diagnosis until strangulation occurs.
    • Ventral: Hernia due to defect in the anterior abdominal wall, which may be spontaneous or acquired. Consists of several subtypes.
      • Umbilical: Most commonly due to increased intraabdominal pressure (ascites, obesity, pregnancy). Patients with ascites and cirrhosis are at high risk for strangulation and rupture.
      • Epigastric and hypogastric.
      • Incisional: Due to inadequate wound healing, wound infection, or excess abdominal wall tension. Make up 20% of abdominal wall hernias. High recurrence rate (50%).
      • Spigelian: Lateral ventral hernia arising at the lateral edge of rectus muscle and arcuate line; almost always acquired. Difficult to diagnose, as pain is typically anterior.
  • History and Exam:
    • Inquire about similar episodes, fever, redness, pain/tenderness at site. Evaluate for obstruction (see this EM@3AM). Pay close attention to prior history of gastric bypass surgery (internal hernia).
    • Assess for evidence of incarceration and strangulation (erythema, warmth, pain) and obstruction.
  • Differential: Hidradenitis, abscess, cyst, lymphoma, hydrocele, varicocele, other hernia types, femoral aneurysm, orchitis, Fournier gangrene, cellulitis.
  • Diagnostics:
    • Laboratory assessment is not routinely needed unless concern for strangulation is present based on history and exam. If concern is present, obtain CBC, LFTs, renal function, lipase, and lactate. Most tests are not sensitive or specific.
    • Imaging:
      • US can assess for hernia size, contents, location. It has a sensitivity and specificity approaching 100% for inguinal hernias. US can also assess for evidence of incarceration and strangulation.
      • CT should be obtained if other items are on the differential or concerned for obstruction or strangulation, as well as evaluate for more uncommon types: femoral, Spigelian, obturator, internal, etc.
  • Management: Depends on hernia type and whether the hernia is incarcerated or strangulated.   Do NOT reduce a strangulated hernia, which can result in perforation and sepsis if strangulated.
    • To reduce hernia: Provide analgesia, place in supine Trendelenberg position, place cold packs to hernia site, apply firm and steady pressure to distal part and to the proximal part of the hernia at the site of the fascial defect.
    • If successful, observe and reevaluate with repeat exams. Beware of “reduction en mass”, or when an incarcerated hernia is reduced but a loop of bowel remains within the hernia sac after reduction. Patients will typically demonstrate signs of incarceration.
    • If hernia remains reduced, the patient can be discharged with outpatient surgical follow-up.
    • If hernia appears strangulated, consult surgery emergently, provide broad-spectrum antibiotics and fluids, and obtain laboratory assessment.

What is the most common type of hernia found in women?

A. Femoral hernia

B. Inguinal hernia

C. Obturator hernia

D. Umbilical hernia


Answer: B

Nearly three-quarters of all hernias found are inguinal hernias. While inguinal hernias are more common in men than women, they are still the most common type of hernia found in women as well. Inguinal hernias can either be direct or indirect. Indirect hernias are the more common of the two and are the result of a hernia sac protruding through the patent processus vaginalis. Direct hernias are due to a defect of the transversalis fascia in Hesselbach triangle. Unlike men, groin hernias in women do not often present with a visible bulge. They often complain of a heaviness or dull discomfort in the groin or pelvic discomfort which is exacerbated by heavy lifting, straining or prolonged standing. As physical exam findings are typically lacking in women with inguinal hernias, diagnosis depends on a high clinical suspicion and ultrasonography or computed tomography.

Femoral hernias (A) occur when the hernia sac protrudes through the femoral canal, resulting in the bulge or mass below the inguinal ligament. They are much more commonly seen in women than men (although still less common than inguinal hernias overall) and are more likely to result in incarceration or strangulation. Obturator hernias (C) develop in the obturator foramen and are more common in elderly women, usually in the setting of significant weight loss. As they do not produce an external or palpable mass, diagnosis is very challenging. Patients can present with pain and decreased sensation along the medial thigh to the knee or symptoms associated with small bowel obstruction if the hernia becomes incarcerated. Umbilical hernias (D) are typically acquired in adults, resulting from conditions that increase intra-abdominal pressure such as ascites, obesity and pregnancy. Incarceration is unusual with umbilical hernias. The majority of umbilical hernias in infants and young children, which result from incomplete closure of the umbilical ring, close spontaneously.

Rosh Review Website Link


  1. Matthews RD, Neumayer L. Inguinal hernia in the 21st century: an evidence based review.Curr Probl Surg 45: 261, 2008.
  2. Salameh JR: Primary and unusual abdominal wall hernias. Surg Clin North Am 88: 45, 2008.
  3. Jamadar DA, Franz GM: Inguinal region hernias. Ultrasound Clin 2: 714, 2007.
  4. Bradley M, Morgan D, Pentlow B, et al. The groin hernia: an ultrasound diagnosis? Ann R Coll Surg Engl 85: 178, 2003.
  5. Scherer LR 3rd, Grosfeld JL. Inguinal hernia and umbilical anomalies. Pediatr Clin North Am 40: 1121, 1993.
  6. Fraser GC Reduction of an incarcerated hernia. J Pediatr Surg 28: 1519, 1993.
  7. Mulholland MW, Lillemoe KD, Doherty GM, et al. Abdominal wall hernias, in Greenfield’s Surgery: Scientific Principles and Practice, 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins, 2011.
  8. Parvey LS, Himmelfarb E, Rabinowitz. Spontaneous reduction of hernia “en masse.” AJR Am J Roentgenol 121: 252, 1974.

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