Semester 2 Anatomy - Stomach & Spleen

The spleen is not in contact with the jejunum. The jejunum lies medial and inferior to the spleen. The kidney is in contact with the posteromedial surface of the spleen. The left colic flexure is in contact with the inferomedial surface of the spleen. The tail of the pancreas touches the hilum of the spleen. The stomach is in contact with the anteromedial surface of the spleen. See Netter Plate 289 for a picture of the different impressions on the spleen.

Pyloric stenosis is a congenital disorder in which the pylorus is thickened causing obstruction of the gastric outlet to the duodenum. This problem is more commonly seen in males. Symptoms like projectile vomiting appear several weeks after birth.

The left gastric artery is the artery that supplies the lesser curvature of the stomach (along with the right gastric artery.) These two arteries would be most likely to cause bleeding at the lesser curvature of the stomach. The left gastric is one of the three arteries that comes off of the celiac trunk. The left and right gastro-omental arteries are the two arteries that supply the greater curvature of the stomach. The gastroduodenal artery is a branch off the common hepatic artery that supplies the duodenum, head of the pancreas, and the greater curvature of the stomach. The short gastric arteries are 4 or 5 small arteries from the splenic artery that supply the fundus of the stomach.

The spleen is usually well protected by the 9th through 12th ribs on the left side. But, if one or more of these ribs gets fractured, the spleen is the first organ to be ruptured. The spleen can also be damaged if there is blunt trauma to the abdomen or a sudden increase in intraabdominal pressure. This patient has several symptoms of a ruptured spleen--she has tenderness on the left posterior axillary line and hypotension. (Because of its spongy parenchyma and thin capsule, a ruptured spleen will bleed profusely and a patient may become hypotensive.) The stomach, splenic flexure of the colon, tail of the pancreas, left kidney, and suprarenal gland are in the same quadrant of the abdomen, and they are also at risk for injury. But, you should remember that the spleen is at greatest risk because of its close relationship with the 9th through 12th ribs.

The spleen and pancreas develop behind the stomach in the dorsal mesogastrium; the liver develops in the ventral mesogastrium. The spleen is not a retroperitoneal organ--it is covered by visceral peritoneum on all its surfaces.

For a good understanding of this question, take a look at Netter Plate 290. The gastroduodenal artery is a branch of the common hepatic artery; it descends behind the first part of the duodenum. So, if an ulcer destroyed the posterior wall of the duodenum, gastric juices could escape and destroy the gastroduodenal artery. The common hepatic artery is a branch of the celiac trunk found superior to the duodenum. The left gastric artery is a branch of the celiac trunk which supplies the left side of the lesser curvature of the stomach. The proper hepatic artery is a branch of the common hepatic artery; it travels superiorly from the common hepatic artery to give off the right, middle, and left hepatic arteries. Finally, the superior mesenteric artery originates from the aorta at the bottom of the L1 level, posterior to the pancreas. It travels over the 3rd part of the duodenum and supplies the intestines, up to the last third of the transverse colon.

The duodenum is not in contact with the spleen. The inferior portion of the spleen contacts the left colic flexure. The superior portion of the spleen contacts the diaphragm--the spleen is convexly curved to fit the concavity of the diaphragm. The tail of the pancreas inserts into the hilum of the spleen. The stomach contacts the anteriomedial portion of the spleen. You should really know what organs contact the spleen and where these organs contact the spleen!

The epiploic (omental) foramen is a passageway between the greater peritoneal sac and the lesser peritoneal sac. It is located posterior to the hepatoduodenal ligament and the first part of the duodenum. The caudate lobe of the liver forms the posterior wall of the epiploic foramen. The aorta is retroperiteoneal, and it does not form a boundary of this foramen

The spleen is a peritonealized organ that is attached to the left colic flexure. It could tear if there was too much traction while pulling the descending colon away from the body wall. Another clue in this scenario that points to a ruptured spleen is the large amount of blood that fills the operative field. The spleen is covered by a very thin capsule, and it has a soft and pulpy parenchyma. So, when it is ruptured, the spleen bleeds profusely. The duodenum and liver are not associated with the left colic flexure. The kidney and suprarenal glands are retroperitoneal organs that are not associated with any mesenteric attachment.

The spleen is the only organ listed which is covered entirely by visceral peritoneum. About the other organs... The kidney and suprarenal glands are retroperitoneal organs. This is different than the secondarily retroperitoneal organs that started out in a mesentery and then got pushed against the posterior wall. The kidneys and the suprarenal glands began developing in the retroperitoneum and stayed there. The duodenum and pancreas are partially peritonealized and partially retroperitoneal. The first two centimeters of the superior duodenum is peritonealized, but the rest of the duodenum, until the duodenojejunal junction, is retroperitoneal. For the most part, the pancreas is secondarily retroperitoneal, although the tail of the pancreas is peritonealized, lying within the splenorenal ligament.

As it enters the hilum of the spleen, the splenic artery gives off short gastric arteries which supply blood to the fundus of the stomach. These short gastric arteries travel in the gastrosplenic ligament to reach the fundus. The common hepatic artery does not directly supply the stomach--it gives off the gastroduodenal artery, which supplies the right portion of the greater curvature of the stomach with the right gastro-omental artery. The inferior phrenic artery is a branch of the aorta which supplies blood to the diaphragm. The left gastro-omental artery is a branch of the splenic artery which supplies the left half of the greater curvature. The right gastric artery is a branch of the proper hepatic artery which supplies the right half of the lesser curvature. See Netter Plate 290 to get a good picture of these arteries and their areas of distribution.

Netter Plate 288 will help you to understand this answer. The splenic artery is a branch of the celiac trunk. It passes deep to the stomach and sends branches to the pancreas before reaching the spleen. If the posterior wall of the stomach eroded, gastric juices could damage the splenic artery. The gastroduodenal artery lies behind the first portion of the duodenum. An ulcer in this portion of the duodenum might jeopardize the gastroduodenal artery. The common hepatic artery is a branch of the celiac trunk which runs superior to the lesser curvature of the stomach. The left gastroepiploic artery runs on the left side of the greater curvature of the stomach. Finally, the superior mesenteric artery arises from the aorta at the L1 level, posterior to the pancreas. It crosses over the third portion of the duodenum.

Structures involving the spleen and posterior part of the developing stomach (which becomes the greater curvature) are derived from the dorsal mesogastrium. This includes the gastrocolic ligament (including the omental apron), gastrophrenic ligament, gastrosplenic ligament, and the splenorenal ligament. The liver develops in the ventral mesogastrium. This means that any structures involving the liver and its attachment to the lesser curvature of the stomach or the body wall will be derivatives of the ventral mesogastrium. This includes the coronary ligament, the falciform ligament, the left and right triangular ligaments, the hepatogastric ligament, and the hepatoduodenal ligament.

The left colic flexure, also called the splenic flexure, is the point where the colon takes a sharp downward turn. This flexure is the point where the transverse colon ends and the descending colon begins. It is located immediately inferior to the spleen, so an enlarged spleen must move medially to avoid this colic flexure. The stomach lies medial to the speen, and the tail of the pancreas inserts into the hilum of the spleen. These organs would not prevent the spleen from descending inferiorly. The kidney and left renal artery are retroperitoneal organs; they would not obstruct movement of the spleen.

During the development of the gut, there are two mesogastria attaching to the developing stomach: the dorsal mesogastrium and the ventral mesogastrium. Different organs begin to develop in each mesogastrium--the spleen and pancreas develop in the dorsal mesogastrium and the liver develops in the ventral mesogastrium. So, the structures involving the spleen and the posterior part of the developing stomach (which becomes the greater curvature) are derived from the dorsal mesogastrium. These include: the greater omentum (gastrophrenic ligament, gastrosplenic ligament, gastrocolic ligament) and splenorenal ligament. The structures involved with the liver and its attachment to the stomach wall form the ventral mesogastrium. These include the lesser omentum (hepatogastric ligament, hepatoduodenal ligament) and the ligaments of the liver (falciform ligament, coronary ligaments, right and left triangular ligaments). Of the answer choices, only the greater omentum is part of the dorsal mesogastrium.

The vagal branches to the stomach are found on the lesser curvature. The anterior vagal branches are derived from the left vagal nerve and the posterior vagal branches are derived from the right vagal nerve. This makes sense, since during the rotation of the gut, the left side of the stomach rotated to become the ventral aspect of the stomach. Vagotomies are done to reduce the acid secretion of the stomach, since the vagus sends one of the signals that stimulates the parietal cells of the stomach to release HCl.

If the gastroduodenal artery and its branches were ligated, blood would flow in a retrograde direction from the left gastroepiploic artery, which is a branch of the splenic artery, to the right gastroepiploic artery, a ligated branch of the gastroduodenal artery. This flow from the left to right gastroepiploic artery would allow blood to reach the entire greater curvature of the stomach. Remember--there are many anastomoses around the stomach that will allow this organ to receive blood even if one branch is ligated.
The left hepatic artery is a branch of the proper hepatic artery; it supplies blood to the left and quadrate lobes of the liver, as well as part of the caudate lobe. The short gastric arteries are branches of the splenic artery which supply the fundus of the stomach. The left gastric artery is a branch of the celiac trunk which supplies the left portion of the lesser curvature. Omental branches are branches of the left and right gastroomental arteries which supply the greater omentum.

The splenorenal ligament is the peritoneal structure that connects the spleen to the posterior abdominal wall over the left kidney. It also contains the tail of the pancreas. The gastrocolic ligament connects the greater curvature of the stomach with the transverse colon. The gastrosplenic ligament connects the greater curvature of the stomach with the hilum of the spleen. The phrenicolic ligament connects the splenic flexure of the colon to the diaphragm. Finally, the transverse mesocolon connects the transverse colon to the posterior abdominal wall.

The short gastric arteries branch from the splenic artery near the hilum of the spleen. They travel in the gastrosplenic ligament to supply the fundus of the stomach. So, these arteries might be damaged if the gastrosplenic ligament was disrupted. The left gastric artery is a branch of the celiac trunk which supplies the left half of the lesser curvature. The splenic artery travels deep to the stomach to reach the hilum of the spleen. Although its branches travel in the gastrosplenic ligament, the splenic artery passes within the splenorenal ligament to reach the splenic hilum, and it would not be damaged by an incision in gastrosplenic ligament. The middle colic artery is a branch of the superior mesenteric artery which supplies the transverse colon. The caudal pancreatic artery is a branch of the splenic artery which supplies the tail of the pancreas. It, along with most of the pancreas, is retroperitoneal.

The hepatic branch of the anterior vagal trunk travels in the upper portion of the hepatogastric ligament. The posterior vagal trunk supplies a celiac branch deep to the hepatogastric ligament. The greater thoracic splanchnic branches to the suprarenal glands come off the greater thoracic splanchnic nerves as they pass through the diaphragm. Then, the greater thoracic splanchnic nerves continue on to synapse in the celiac ganglia.