Merck Manual

Please confirm that you are a health care professional

honeypot link

Hernias of the Abdominal Wall


Parswa Ansari

, MD, Hofstra Northwell-Lenox Hill Hospital, New York

Last full review/revision Sep 2021| Content last modified Sep 2021
Click here for Patient Education
Topic Resources

A hernia of the abdominal wall is a protrusion of the abdominal contents through an acquired or congenital area of weakness or defect in the wall. Many hernias are asymptomatic, but some become incarcerated or strangulated, causing pain and requiring immediate surgery. Diagnosis is clinical. Treatment is elective surgical repair.

Abdominal hernias are extremely common, particularly among males, necessitating about 700,000 operations each year in the US.

Classification of Abdominal Hernias

Abdominal hernias are classified as either

  • Abdominal wall hernias

  • Groin hernias

About 75% of all abdominal hernias are inguinal. Incisional hernias comprise another 10 to 15%. Femoral and unusual hernias account for the remaining 10 to 15%.

Abdominal wall hernias

Abdominal wall hernias include

  • Umbilical hernias

  • Epigastric hernias

  • Spigelian hernias

  • Incisional (ventral) hernias

Umbilical hernias (protrusions through the umbilical ring) are mostly congenital, but some are acquired in adulthood secondary to obesity, ascites, pregnancy, or chronic peritoneal dialysis.

Epigastric hernias occur through the linea alba.

Spigelian hernias occur through defects in the transversus abdominis muscle lateral to the rectus sheath, usually below the level of the umbilicus.

Incisional hernias occur through an incision from previous abdominal surgery.

Groin hernias

Groin hernias include

  • Inguinal hernias

  • Femoral hernias

Inguinal hernias occur above the inguinal ligament. Indirect inguinal hernias traverse the internal inguinal ring into the inguinal canal, and direct inguinal hernias extend directly forward and do not pass through the inguinal canal. (See also Inguinal hernia in neonates Inguinal hernia in neonates Inguinal hernias develop most often in male neonates, particularly if they are premature (in which case the incidence is about 10%). The right side is affected most commonly, and about 10% of... read more .)

Femoral hernias occur below the inguinal ligament and go into the femoral canal.

Sports hernias

A sports hernia is not a true hernia because there is no abdominal wall defect through which abdominal contents protrude. Instead, the disorder involves a tear of one or more muscles, tendons, or ligaments in the lower abdomen or groin, particularly where they attach to the pubic bone. It is more appropriately termed athletic pubalgia.

Symptoms and Signs of Abdominal Wall Hernias

Most patients complain only of a visible bulge, which may cause vague discomfort or be asymptomatic. Most hernias, even large ones, can be manually reduced with persistent gentle pressure; placing the patient in the Trendelenburg position may help. An incarcerated hernia cannot be reduced and can be the cause of a bowel obstruction. A strangulated hernia causes steady, gradually increasing pain, typically with nausea and vomiting. The hernia itself is tender, and the overlying skin may be erythematous; peritonitis may develop depending on location, with diffuse tenderness, guarding, and rebound.

Diagnosis of Abdominal Wall Hernias

  • Clinical evaluation

The diagnosis of an abdominal hernia is clinical. Because the hernia may be apparent only when abdominal pressure is increased, the patient should be examined in a standing position. If no hernia is palpable, the patient should cough or perform a Valsalva maneuver as the examiner palpates the abdominal wall. Examination focuses on the umbilicus, the inguinal area (with a finger in the inguinal canal in males), the femoral triangle, and any incisions that are present.

Inguinal masses that resemble hernias may be the result of adenopathy (infectious or malignant), an ectopic testis, or lipoma. These masses are solid and are not reducible. A scrotal mass may be a varicocele, hydrocele, or testicular tumor. Ultrasound may be done if physical examination is equivocal.

Prognosis for Abdominal Wall Hernias

Congenital umbilical hernias rarely strangulate and are not treated; most resolve spontaneously within several years. Very large defects may be repaired electively after age 2 years.

Umbilical hernias in adults cause cosmetic concerns and can be electively repaired; strangulation and incarceration are unusual but can happen and usually contain omentum rather than intestine.

Treatment of Abdominal Wall Hernias

  • Surgical repair

Groin hernias typically should be repaired electively because of the risk of strangulation, which results in higher morbidity (and possible mortality in older patients). Asymptomatic inguinal hernias in men can be observed; if symptoms develop, they can be repaired electively. Repair may be through a standard incision or laparoscopically.

An incarcerated or strangulated hernia of any kind requires urgent surgical repair.

Click here for Patient Education
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
Professionals also read
Test your knowledge
Whipple Disease
Whipple disease predominantly affects white men 30 to 60 years of age. Affected patients may have subtle defects of cell-mediated immunity that predispose to infection with T. whipplei. Of the patients with this disease, approximately what percentage have a positive result on HLA-B27 test?
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID