Richter’s femoral hernia: not every left lower quadrant pain means diverticulitis

52 year-old woman, with a history of diverticulitis, consults the Emergency Department with a new episode of recurrent abdominal pain. It is intense, colicky and mostly located in the left iliac fossa, and is accompanied with queasiness. Acute diverticulitis was suspected. However, in the left inguinal region, medial to the femoral vessels, a painful, non-reducible femoral hernia is palpated. Ultrasound and MDCT are performed, showing a 1.5 x 1 cm femoral hernia containing the antimesenteric wall of a jejunal segment as well as free fluid. This short segment showed parietal thickness and an initial change in caliber, with proximal jejunal dilatation and distal ileum collapse. No established signs of ischemia or closed loop herniated bowel were seen. The diagnosis was incarcerated Richter’s femoral hernia with proximal jejunal obstruction. Urgent surgery was performed, which confirmed the radiological findings.

Richter’s hernias are a rare type of hernia referring to the herniation of the antimesenteric wall of the bowel that does not compromise the entire wall circumference. It frequently occurs in the terminal ileum, and is usually associated with femoral hernias. These hernias are most prone to incarceration and strangulation and progress more rapidly to gangrene than other strangulated hernias but obstruction is less frequent. When these complications are present, symptoms include abdominal pain, vomiting and/or distended abdomen. Physical examination would reveal a nonreducible abdominal mass.Imaging studies are required when the clinical manifestations are misleading or inconclusive, or preoperative assessment of the hernia and its potential complications is required, MDCT being the imaging modality of choice.Incarceration consists of an inability to manually reduce the hernia. We can suggest this diagnosis through imaging when the hernia occurs through a small defect in the abdominal wall and/or the hernia sac has a narrow neck. Strangulation refers to a compromise of the blood supply. We can suspect impending strangulation when there is free fluid within the hernia sac, bowel wall thickening or luminal dilatation.Early surgical management is often necessary when complications are present.

Richter’s hernias are an infrequent type of hernia with a higher risk of complications, such as incarceration, strangulation and bowel obstruction. Proper recognition will allow an early diagnosis, appropriate treatment and, consequently, a better prognosis.

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