Femoral hernias constitute up to 2% to 4% of all groin hernias; 70% occur in women. Approximately 25% of femoral hernias become incarcerated or strangulated, and a similar number are missed or diagnosed late.
The abdominal viscera and peritoneum protrude through the femoral canal into the upper thigh. The boundaries of the femoral canal are the lacunar ligament medially, the femoral vein laterally, the iliopubic tract anteriorly, and the Cooper ligament posteriorly.
Symptoms. Patients may complain of an intermittent groin bulge or a groin mass that may be tender. Because femoral hernias have a high incidence of incarceration, small-bowel obstruction may be the presenting feature in some patients. Elderly patients, in whom femoral hernias occur most commonly, may not complain of groin pain, even in the setting of incarceration. Therefore, an occult femoral hernia should be considered in the differential diagnosis of any patient with small-bowel obstruction, especially if there is no history of previous abdominal surgery.
Physical examination. The characteristic finding is a small, rounded bulge that appears in the upper thigh just below the inguinal ligament. An incarcerated femoral hernia usually presents as a firm, tender mass. The differential diagnosis is the same as for inguinal hernia.
Radiographic evaluation. Radiographic studies are rarely indicated. Occasionally, a femoral hernia is found on a CT scan or gastrointestinal contrast study performed to evaluate a small-bowel obstruction.