Intersigmoid hernias, also known as sigmoid mesocolon hernias, (alternative plural: herniae) occur when small bowel loops protrude into a peritoneal pocket (intersigmoid fossa) formed between two adjacent sigmoid segments and their mesentery.
Epidemiology
Sigmoid mesocolon hernias account for ~5% of all internal hernias 1,2.
Pathology
Some authors divide sigmoid mesocolon hernias into three categories 1,3:
- intersigmoid hernia
- transmesosigmoid hernia
- intermesosigmoid hernia
It is difficult, maybe impossible, to distinguish these subtypes preoperatively with no clear radiographic sign identified to distinguish among the three subtypes 1,2. Thus, most radiologists and surgeons just refer to intersigmoid hernias, rather than trying to differentiate between them.