Abdomen Flashcards
Superficial fascia above the umbilicus
Single sheet of connective tissue, it is continuous with the superficial fascia in other regions of the body
Superficial fascia below the umbilicus
Two layers- fatty superficial layer and the membranous deep layer
superficial vessels and nerves run between them
What is the linea alba?
Fibrous structure that extends from the xiphoid process of the sternum to the pubic symphysis
formed by the entwining of flat muscle aponeuroses
Function of the external oblique
Contralateral rotation of the torso
External oblique
attachments- originates form ribs 5-12, inserts into iliac crest and pubic tubercle
runs in an inferiomedial direction, perpendicular to internal
Function of the internal oblique
Bilateral contraction compresses the abdomen
unilateral contraction ipsilaterally rotates the torso
Internal oblique
attachments- originates from inguinal ligament, iliac crest and lumbodorsal fascia, and inserts into ribs 10-12
runs in a superomedial direction, perpendicular to external
Transversus abdominus
Deepest part of flat muscles, runs in a transverse direction
Where does the transversus abdominus originate and insert into?
origin- inguinal ligament, costal cartilages 7-12, iliac crest
inserts- xiphoid process, linea alba and pubic crest
Rectus abdominus
Long paired muscle split in half by the linea alba, has fibrous strips called tendinous intersections
originates from pubic crest, inserts into xiphoid process
What is the function of the rectus abdominus?
Assists the flat muscles in compressing abdominal viscera
stabilises the pelvis during walking and deppresses ribs
What is the function of the transversus abdominus?
Compression of abdominal contents
What is the rectus sheath?
Encloses the rectus abdominus
formed by the aponeuroses of the three flat muscles
What is the foregut?
Mouth region to the second part of the duodenum, where the bile duct input is
What is the midgut?
End of the foregut to halfway through the transverse colon
What is the hindgut?
Last portion of the descending colon, sigmoid colon and the rectum
What vessel is the foregut supplied by?
Celiac trunk
What vessel is the midgut supplied by?
Superior mesenteric artery
What vessel is the hindgut supplied by?
Inferior mesenteric artery
What is the mesentery?
Double fold of peritoneal tissue that suspends the small intestine and large intestine from the posterior abdominal wall
Classified as an organ due to contiguous structure
What is the function of the mesentery?
Anchors intestines in place while still allowing some movement
provides a conduit for blood vessels, nerves and lymphatic vessels
What is the greater omentum?
Part of the peritoneum that hangs down the curvature of the stomach like an apron
can travel to areas of injury/damage and wraps round to protect it
What is the falsiform ligament?
Attachment of the liver to the anterior abdominal wall
splits the left and right lobes of the liver
Duodenum
First part of the small intestine
C shape around the pancreas
What are pilcae circularis?
Bteween end of duodenum and ileum, slow down movement of food and increase surface area for absorption of nutrients
What is the major duodenal papilla?
Opening at which bile and pancreatic secretions enter the hepatopancreatic ampulla
What does retroperitoneal mean?
Only covered anteriorly by the peritoneum
What does intraperitoneal mean?
Covered by peritoneum on both sides so it is within it
Where is the duodenojejunal flexture?
Where the duodenum meets the jejnum at a sharp turn
How is the small intestine covered by peritoneum?
Initial part of superior duodenum is intraperitoneal
remainder is retroperitoneal
How is the stomach covered by peritoneum?
Intraperitoneal
What are the four parts of the stomach?
Cardia, fundus, body, pylorus
What is the hepatogastric ligament?
Joins the stomach to the liver at the lesser curvature
What vessels supply the greater curvature of the stomach?
Short gastric arteries and the left gastro-omental arteries
What vessels supply the lesser curvature of the stomach?
Left gastric artery and right gastric branch of the hepatic artery
What are the two sphincters of the stomach?
Inferior oesophageal sphincter and pyloric sphinctor
What does the pyloric sphincter control?
The exit of chyme from the stomach when intragastric pressure overcomes the resistance of the pylorus
What is the lesser omentum?
Arises at the lesser curvature and ascends to attach to the liver
Stomach innervation
Parasympathetic- anterior and posterior gastric nerves
Sympathetic- celiac plexus
Pancreas relation to the peritoneum
Mostly retroperitoneal apart from the tail
Tail lies within the splenorenal ligament so it is intraperitoneal
What is the ampulla of vater?
Where the bile duct and main pancreatic duct join together, where the digesitve juices enter into the 2nd part of the duodenum via the major duodenal papilla
Splenic artery
Part of the celiac trunk and comes off the aorta
Supplies blood to the spleen but also to the body and tail of the pancreas
Job is to decrease blood pressure as it enters the spleen
What is the function of the spleen?
largest secondary lymphoid organ in the body so filters blood and presents any antigens which results in the maturation of lymphocytes
role in degradation of erythrocytes
How is the spleen related to the peritoneum?
Left side of the greater omentum extends to the spleen as the gastrosplenic ligament and then splits to wrap aorund it so it is intraperitoneal
continues to the left kidney as the splenorenal ligament
Branches of the celiac trunk
common hepatic artery going to the right side of the body
splenic artery and left gastric arteries both go to the left
What does the left gastric artery supply?
some of the oesophagus and the lesser curvature of the stomach
