Littre hernia: surgical anatomy, embryology, and technique of repair.

Littre hernia is the protrusion of a Meckel diverticulum through a potential abdominal opening. Alexis de Littre (1700) reported ileal diverticula and attributed them to traction. August Gottlieb Richter (1785) defined them as preformed, and Johann Friedrich Meckel (1809) postulated their embryologic origin. Sir Frederic Treves (1897) distinguished between Littre and Richter hernia (partial enterocele). Embryologically, Meckel diverticulum is the persistent intestinal part of the omphaloenteric duct through which the midgut communicates with the umbilical vesicle until the fifth week. It is found at the antimesenteric border of the ileum, usually located 30 to 90 cm from the ileocecal valve, measuring 3 to 6 cm in length and 2 cm in diameter. Usual sites of Littre hernia are: inguinal (50%), umbilical (20%), and femoral (20%). Meckel diverticulum may be accompanied in the sac by the ileal loop to which it is attached; rarely, it may undergo incarceration or strangulation, necrosis, and perforation. In children, it is mostly found in umbilical hernias, and the diverticulum is more prone to adhere to the sac. Repair of Littre hernia consists of resection of the diverticulum and herniorraphy; in perforated cases, care must be taken to not contaminate the hernia field.