Greater Omentum

omentum majus

The greater omentum is a large peritoneal apron hanging from the greater curvature of the stomach and the transverse colon, folding back to form a four-layered sheet containing fat, lymphatics, blood vessels, and immunologically active cells.

Region: Abdomen

Biomechanics

Function & Actions

The "policeman of the abdomen" — migrates to sites of intraperitoneal inflammation or perforation to wall off infection. Provides a highly vascular peritoneal surface for fluid absorption, contains immunologically active milky spots (macrophage aggregates), and insulates abdominal contents.

Clinical Relevance

Clinical Notes

Omental infarction from torsion or avulsion produces acute abdominal pain mimicking appendicitis. The greater omentum is used as a pedicled or free flap for reconstruction — omentoplasty fills dead space after radical resections, chest wall defects, and brain tumour cavities. In peritoneal carcinomatosis, omental involvement (omental caking) indicates advanced disease.

Pathology

Common Injuries & Conditions

Omental Torsion

Primary or secondary torsion of the greater omentum producing acute right-sided abdominal pain mimicking appendicitis, confirmed by CT and managed laparoscopically by omentectomy.

Omentoplasty for Dead Space Obliteration

Pedicled greater omentum transposed through the diaphragm to fill intrathoracic dead space after lung resection or sternal reconstruction.