Cases

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Small-bowel obstruction due to right femoral hernia: CT scan at the level of pelvic inlet shows dilated, fluid-filled small-bowel loops, with locules of air in the nondependent portion (B). Similarly, scans of the groin show locules on the right, medial to the femoral vein (C). Scans through the lower groin region show the loop of bowel with air locule at the site of the femoral canal (D). The presence of bowel loops in the femoral canal indicates a femoral hernia, which is the cause of the small-bowel obstruction in this patient (A, B).

Small-bowel obstruction is a common surgical emergency. Most often, the causes are adhesions secondary to a previous abdominal surgery. Other causes include gallstone ileus, hernia, tumor, volvulus, and inflammatory disease. Clinically, patients present with colicky abdominal pain, vomiting, abdominal distension, and constipation. Bowel sounds are hyperactive in the early stages and absent in the later stages. Examination of the hernial orifices may reveal the cause of the problem. Hernial orifices should always be checked for the presence of abnormal bowel loops. Abdominal radiographs show dilated loops of the small bowel. The erect views show multiple fluid levels, and locules of air may produce the string-of-beads sign. Gallstones and air in the biliary tract suggest gallstone ileus.

Inguinal hernia is the most common hernia in both men and women, accounting for approximately 90%. These hernias can be direct or indirect and are usually situated above and medial to the pubic tubercle.

Femoral hernias constitute 5-10% of all groin hernias and are more common in women (80%) than in men. Femoral hernias are due to herniation of a bowel loop through the femoral ring into the femoral canal, which is a continuation of the femoral sheath medial to the femoral vein and below the level of the inguinal ligament. The hernia is usually inferior and lateral to the pubic tubercle. The femoral ring is a narrow structure, and any herniation can lead to obstruction or strangulation. Predisposing factors include conditions that increase intra-abdominal pressure, such as chronic constipation, prostatic problems, and chronic lung diseases.

The condition is managed by means of nasogastric suction, surgical repair of the femoral hernia, and surgical relief of the obstruction.

For more information on small-bowel obstruction, see the eMedicine articles Obstruction, Small Bowel (within the Emergency Medicine specialty) and Small-Bowel Obstruction (within the Radiology specialty).