Posterior wall of stomach

The posterior wall of stomach, also known as the postero-inferior surface, forms the posterior aspect of the organ and is covered by visceral peritoneum, except for a small area near the cardiac orifice. The orientation of this surface varies with the degree of gastric distension. When the stomach is contracted, its surfaces are directed predominantly upward and downward; however, as the stomach distends, they become directed forward and backward. Accordingly, the gastric surfaces are described as the anterosuperior and posteroinferior surfaces.

Relations

The postero-inferior surface rests upon a group of structures collectively known as the stomach bed. These structures include the diaphragm, spleen, left suprarenal gland, upper part of the anterior surface of the left kidney, anterior surface of the pancreas, left colic (splenic) flexure, and the upper layer of the transverse mesocolon. The transverse mesocolon also separates the stomach from the duodenojejunal flexure and adjacent loops of the small intestine.

Most of the postero-inferior surface is covered by peritoneum and is separated from the stomach bed by the lesser sac (omental bursa). However, a small non-peritoneal area adjacent to the cardiac orifice, bounded by the attachments of the gastrophrenic ligament, lies directly against the diaphragm.

Clinical correlate

The close relationship of the posterior wall to the structures of the stomach bed is of considerable clinical importance. Posterior gastric ulcers may penetrate the stomach wall and involve the pancreas, causing referred back pain or pancreatitis. Erosion into the splenic artery may result in severe haemorrhage.

Vasculature

• The arterial supply of the posterior wall of stomach is derived primarily from branches of the left and right gastric arteries along the lesser curvature, the left and right gastroomental (gastroepiploic) arteries along the greater curvature, and the short gastric arteries supplying the fundus.

• Venous drainage accompanies the corresponding arteries and ultimately drains into the portal venous system through the gastric, gastroomental, and splenic veins.