Lesser Curvature of the Stomach

The lesser curvature of the stomach is the shorter, concave medial border of the stomach, forming a gentle curve between the cardia and pylorus. It serves not only as an important anatomical landmark but also as a conduit for major blood vessels, a site of frequent ulceration, and a surgical reference point. Compared to the greater curvature, it is more fixed and less mobile, providing structural orientation during imaging and operative procedures.

Structure

The lesser curvature extends from the cardiac notch (incisura cardiaca) at the junction of the esophagus and stomach to the angular notch (incisura angularis), where the body transitions to the pyloric part. It lies along the superior and medial aspect of the stomach. The curvature is sharply concave and relatively short compared to the greater curvature.

The surface of the lesser curvature is lined internally with gastric mucosa that transitions smoothly into the adjacent stomach walls. The mucosa may show prominent rugae, especially near the angular notch. Underneath, the muscular wall maintains the standard layers of gastric tissue: mucosa, submucosa, muscularis externa, and serosa.

Key Anatomical Features

• Angular notch: A noticeable indentation that marks the junction between the body and pyloric antrum.
• Peritoneal covering: The lesser curvature is covered by visceral peritoneum and is associated with the lesser omentum, which connects it to the liver.

Location

The lesser curvature lies along the superomedial border of the stomach and spans the following anatomical zones:

• Starts at the cardia, just below the gastroesophageal junction.
• Arches downward and to the right, passing the angular notch.
• Ends at the pylorus, near the duodenal opening.

It is in close proximity to the liver (especially the left lobe) and is anterior to the pancreas. The lesser omentum attaches along its length and extends upward to the liver, forming the hepatogastric ligament.

Function

Although the lesser curvature does not have a distinct physiological role separate from the stomach itself, it performs key supportive functions:

• Conduction of contents: Serves as a guide path for chyme during gastric peristalsis toward the pylorus.
• Attachment for lesser omentum: Anchors the hepatogastric ligament, allowing passage of key vascular structures between the stomach and liver.
• Vascular conduit: Provides a route for the left and right gastric arteries along the inner curvature, forming important anastomoses.

Clinical Significance

The lesser curvature is a clinically significant zone due to its anatomical relationships and susceptibility to pathology:

• Peptic ulcers: The most common site of gastric ulcers, especially near the angular notch, due to exposure to gastric acid and lower mucosal protection in this region.
• Gastric cancer: Early-stage carcinomas frequently develop along the lesser curvature and may initially go unnoticed due to subtle symptoms.
• Surgical landmark: Used as a reference point in procedures such as subtotal gastrectomy, Billroth I and II anastomoses, and vagotomy.
• Vascular supply: The left gastric artery (from the celiac trunk) and right gastric artery (from the common hepatic artery) run along the curvature and must be carefully preserved or ligated during surgery.
• Lymphatic drainage: Important drainage route to the gastric and celiac lymph nodes; involvement here can indicate metastasis from gastric malignancies.

Due to its anatomical consistency and prominent vasculature, the lesser curvature is a central feature in radiographic imaging and upper endoscopic procedures. Lesions in this area often present with localized epigastric pain, especially after meals.