A case of sciatic hernia incarcerated through lesser sciatic foramen

We report a case of sciatic hernia incarcerated through the left lesser sciatic foramen. A 75-year-old woman seen for small bowel obstruction with abdominal distention, pain, and anorexia was found in digital rectal examination to have a bulge outside the left rectal wall. Computed tomography and magnetic resonance imaging showed the small intestine protruding from the pelvis through the lesser sciatic foramen, necessitating emergency surgery. The small intestine 5cm proximal to the cecum was incarcerated through the left lesser sciatic foramen as a Richter hernia. The incarcerated intestine was manually repositioned and ileocecal resection conducted due to ischemic intestinal change. The foramen defect was repaired directly by suturing the mesosalpinx. Hernia from the lesser sciatic foramen has not, to our knowledge, been reported in Japan.