sp14_-_human_anatomy_exam_2_20141210195155 Flashcards
What are the 2 ways to divide the abdomen?
- 9 region- quadrants
What are the layers of the anterior abdominal wall?
- skin (superficial)- camper fascia - superficial fatty layer of subcutaneous tissue- scarpa fascia - deep membranous layer of subcutaneous tissue- investing fascia - wraps around and between the following muscles: - external oblique muscle - internal oblique muscle - transversus abdominis muscle- endo-abdominal (transversalis) fascia- extraperitoneal fat- parietal peritoneum
What are the muscles of the abdominal wall?
- external oblique muscle- internal oblique muscle- transversus abdominis muscle- rectus abdominis muscle- pyramidalis muscle
What muscles form the aponeurosis in the anteriolateral abdominal wall?
external obliuqe, internal oblique, and transversus abdominus muscles
What is the linea alba?
a midline raphe formed by the interweaving of the aponeuroses which extends from the xiphoid process to the pubic symphysis; between right and left sides as well as between superficial, intermediate, and deep layers
What is the rectus sheath? What does it envelope? Name the layers.
- aponeurotic (tendinous) sheath- envelopes rectus abdominus and pyramidalis muscles- consists of anterior and posterior layers
How does the composition of the ANTERIOR layer of the rectus sheath change from above the arcuate line to below the arcuate line?
- superior to arcuate line - formed by aponeuroses of external oblique and 1/2 inferior oblique muscles- inferior to arcuate line - formed by aponeuroses of external oblique, internal oblique and transversus abdominis muscles
How does the composition of the POSTERIOR layer of the rectus sheath change from above the arcuate line to below the arcuate line?
- superior to arcuate line - formed by aponeuroses of transversus abdominis and 1/2 internal oblique muscles and transversalis fascia- inferior to arcuate line - formed by transversalis fascia
What are the 3 infraumbilical peritoneal folds? How many of each are there? What do they each cover?
- median umbilical fold (1) - from urinary bladder to umbilicus; covers median umbilical ligament- medial umbilical folds (2) - covers medial umbilical ligaments; formed by the occluded portions of umbilical arteries- lateral umbilical folds (2) - covers inferior epigastric vessels
What are the superficial vessels of the anterior abdominal region? Where do all of these vessels run (layer)?
- circumflex iliac artery- epigastric artery- circumflex iliac vein- epigastric vein- all of these vessels run in superficial fat and fascia
What is the superficial circumflex iliac artery a branch of? What does it supply?
- branch of the femoral artery- supplies region of inguinal ligament
What is the superficial epigastric artery a branch of? What does it supply?
- branch of the femoral artery- supplies abdomen inferior to umbilicus
What is the superficial circumflex iliac vein drain to? What does it drain?
- drains to the femoral vein- drains region of inguinal ligament
What is the superficial epigastric vein drain to? What does it drain?
- drains to femoral vein- drains abdomen inferior to umbilicus
What is the deep circumflex artery a branch of? Where does it run? What does it supply? How does the vein of the same name differ?
- branch of external iliac artery- runs between internal oblique and transversus abdominis muscles- supplies inferior lateral abdominal muscles- all veins are similarly placed and drain to the external iliac vein
What is the inferior epigastric artery a branch of? Where does it run? What does it supply? What does it anastamose with? How does the vein of the same name differ?
- branch of external iliac artery- enters posterior rectus sheath at arcuate line- supplies lower rectus abdominus muscles- anastamoses with superior epigastric artery- all veins are similarly placed and drain to external iliac vein
What is the superior epigastric artery a branch of? Where does it run? What does it supply? What does it anastamose with? How does the vein of the same name differ?
- branch of internal thoracic artery (mammary)- enters posterior rectus sheath lateral to sternum- supplies upper rectus abdominus muscles- anastomoses with inferior epigastric artery- all veins are similarly placed and drain to internal thoracic vein
What are the nerves of the abdominal wall? Where do they run?
- ventral rami of T7-L1 spinal nerves- run between internal oblique and transversus abdominis muscles
What do each of the nerves of the abdominal wall supply?
- T7, T8, & T9 - supply region above umbilicus- T10 - supplies umbilical region- T11, T12, & L1 - supply region below umbilicus
What can occur if there is an injury to the ventral rami of spinal nerves T11, T12, and L1?
injury to these nerves weakens muscles in inguinal region; predisposes the person to developing direct inguinal hernias
Where is the inguinal region located?
superior to thigh, medial to ilium, and lateral to pubic bone
What does the inguinal region extend between?
area extends between the anterior superior iliac spine (ASIS) and the pubic tubercle
What are the contents of the inguinal region?
- inguinal ligament- inguinal canal (male and female)- superficial and deep rings of the inguinal canal- walls of the inguinal canal
What is the inguinal ligament? What does it extend between? What does it supply?
- folded inferior border of the external oblique aponeurosis- extends from ASIS to pubic tubercle- supplies upper abdominal muscles and diaphragm
What is the inguinal canal? What does it transverse? What other structure does it run by?
- obliquely set tunnel 3-5 cm long- transverses anterior abdominal wall- runs parallel and superior to inguinal ligament
What are the contents of the MALE inguinal canal?
- spermatic cord and its contents (vas deferens, testicular nerves and vessels, cremasteric muscle and fascia)- ilioinguinal nerve (L1)
What are the contents of the FEMALE inguinal canal?
- round ligament of uterus- ilioinguinal nerve (L1)
What are the 2 rings of the inguinal canal? Where do they each open?
- superficial ring - opening in external oblique aponeurosis; obvious triangular opening lateral to pubic tubercle- deep ring - opening in transversalis fascia; subtle piercing just lateral to inferior epigastric vessels
How do the 2 inguinal rings define the inguinal canal?
the canal extends between the superficial and deep inguinal rings
What are the walls of the inguinal canal?
- anterior wall: external oblique aponeurosis- posterior wall: transversalis fascia and conjoint tendon (fusion of internal oblique and transversus abdominis aponeuroses medially)- roof: internal oblique and transversus abdominis muscles- floor: inguinal ligament
What is an abdominal hernia? Where do most hernias occur?
- outpouching of abdominal viscera within a sac- 90% of hernias occur in inguinal region
What are the 3 layers that comprise the hernial sac?
- peritoneum- extraperitoneal fat- transversalis fascia
Where does an indirect inguinal hernia occur?
extends through entire inguinal canal; LATERAL to inferior epigastric vessels; commonly enters scrotum or labia majora
What is the most common type of hernia? Is it more prevalent in males or females?
- indirect inguinal hernia- more prevalent in males than females
In males, what does an indirect inguinal hernia usually result from?
usually from persistent processus vaginalis in males (connects peritoneum with descended testis)
What is an indirect inguinal hernia usually referred to in a female?
canal of Nuck
Where does a direct inguinal hernia occur?
through the inguinal triangle (Hesselbach’s) (inferior epigastric artery, rectus abdominus muscle and inguinal ligament); emerges through conjoint tendon by or at superficial ring; MEDIAL to inferior epigastric vessels; usually does NOT enter scrotum or labia majora
Is a direct inguinal hernia more common in males or females?
males
What is a direct inguinal hernia usually associated with?
usually associated with a weakened abdominal wall
Other than inguinal hernias, what are the 3 other types of abdominal hernias covered in lecture?
- femoral hernia- umbilical hernia- epigastric hernia
What is the most common type of hernia in females?
indirect inguinal hernia
Describe a femoral hernia.
- through the femoral ring and canal- medial compartment of sheath- more common in females than males (femoral ring is wider in females)
Describe an umbilical hernia.
- through the umbilical ring- most common in newborns- more common in females and obese individuals
Describe an epigastric hernia.
- through the linea alba- most common in over 40- usually associated with obesity
What is the inferior epigastric artery a branch of? Where does it run? What does it supply? What does it anastamose with? How does the vein of the same name differ?
- branch of external iliac artery- enters posterior rectus sheath at arcuate line- supplies lower rectus abdominus muscles- anastamoses with superior epigastric artery- all veins are similarly placed and drain to external iliac vein
What is the superior epigastric artery a branch of? Where does it run? What does it supply? What does it anastamose with? How does the vein of the same name differ?
- branch of internal thoracic artery (mammary)- enters posterior rectus sheath lateral to sternum- supplies upper rectus abdominus muscles- anastomoses with inferior epigastric artery- all veins are similarly placed and drain to internal thoracic vein
What is a peritoneum?
thin, translucent, serous membrane
What are the two types of peritoneum? What does each cover?
- parietal peritoneum - lines the inner abdominal wall- visceral peritoneum - covers organs
What does the term retroperitoneal imply?
that the organs are behind the peritoneum
Where do vessels travel with respect to the peritoneum?
vessels travel between the peritoneal layers
What is the peritoneal sac?
all viscera and parietal peritoneal membranes
What is the peritoneal cavity? What does it contain? What is its purpose?
- a potential space within the peritoneal sac- contains only a small amount of serous fluid- allows organs to move freely without friction (ex. peristalsis)
Explain the clinical significance of the peritoneal cavity.
- the potential space (peritoneal cavity) can become an actual space- may contain up to several liters of fluid (ascites)- disease, injury, or infection can lead to pooling of fluids (blood, bile, pus, feces)
Name the 7 double-layered peritoneal folds and ligaments.
- greater omentum- lesser omentum- mesentery proper- suspensory ligament of Treitz- mesocolon- falciform ligament- coronary ligament
What does the greater omentum attach to? What does it cover?
- attaches to the greater curvature of stomach and the transverse colon- drapes over the small intestines like an “apron”
What is another name for the “apron” that drapes over the small intestines and is a part of the greater omentum? How many layers does it have?
- gastrocolic ligament- 4 layers (the double layer goes down and then comes back up to total 4 layers)
What are the three parts of the greater omentum?
- gastrophrenic ligament- gastrosplenic ligament- gastrocolic ligament
What is the clinical significance of the greater omentum?
- functionally, it can wall off infections and inflammation sites- results in formation of adhesions (limit mobility and limit how food can be processed)
What does the lesser omentum attach to?
attaches the lesser curvature of the stomach and duodenum to the liver via 2 ligaments
What are the 2 portions of the lesser omentum? What does each connect?
- hepatogastric ligament - connects liver to stomach- hepatoduodenal ligament - connects liver to duodenum
What is the portal triad? What peritoneal fold/ligament contains this structure?
- hepatic artery, portal vein, and bile duct- hepatoduodenal ligament of the lesser omentum
What does the mesentery proper connect to?
- anchors most of the small intestine to the posterior abdominal wall- runs diagonally from duodenojejunal junction to the ileocecal junction (distance = 15-20 cm in adults)**NOTE: duodenum anchored by the suspensory ligament of Treitz
What is the suspensory ligament of Treitz? What does it connect to? What is its function?
- fibromuscular ligament descends form R. crus of the diaphragm and crosses over L. crus to hold the distal duodenum in place- prevents the duodenojejunal junction from sagging
What is the function of the mesocolon?
anchors portions of the colon to the posterior abdominal wall
Which of the sections of the colon are supported by a mesocolon?
- transverse colon is anchored by transverse mesocolon- sigmoid colon is anchored by sigmoid mesocolon- ascending and descending colon have no mesentery; they attach directly to the posterior wall- rectum is only partially covered with peritoneum
What is the function of the falciform ligament? What does it contain at its inferior border?
- divides liver into right and left lobes; anchors liver to diaphragm and anterior body wall- round ligament of the liver (the obliterated umbilical vein)
What is the coronary ligament? What is its function?
- reflections of peritoneum around the bare area of the liver- attach liver to inferior surface of the diaphragm
Where is the bare area of the liver located?
upper posterior liver
What are the single-layered peritoneal folds? How many of each are there? What does each cover?
- 1 median umbilical fold: covers fetal urachus- 2 medial umbilical folds: covers fetal umbilical arteries- 2 lateral umbilical folds: covers inferior epigastric vessels
What are peritoneal pouches?
potential peritoneal spaces in standing patients; becomes actual spaces in recumbent (horizontally-lying) patents
What are the two peritoneal pouches?
- hepatorenal pouch- rectovesical or rectouterine pouch
What is the clinical significance of peritoneal pouches?
pathological fluids can accumulate in these recesses
What structures surround the hepatorenal pouch?
bounded by liver, right kidney, colon, and duodenum
What is the lowest part of the peritoneal cavity when patient is recumbent (horizontal)?
hepatorenal pouch; fluids may move down to rectovesical/rectouterine pouch when in reclining position or sitting up
What is another name for the hepatorenal pouch?
Pouch of Morrison
In what gender can the rectovesical pouch be found?
male
Where is the rectovesical pouch found? How can fluids move from this pouch to the hepatorenal pouch?
- between the bladder and rectum- fluids here may move up to hepatorenal pouch when in Trendelenburg position (laying down where the feet are higher than the head)
Where is the rectouterine pouch found? How can fluids move from this pouch to the hepatorenal pouch?
- between the rectum and uterus- fluids here may move up to hepatorenal pouch when in Trendelenburg position (laying down where the feet are higher than the head)
What is the function of the liver?
detoxifies chemical products and produces bile
What is the function of the gallbladder?
stores bile for emulsification of fats
What is the function of the pancreas?
produces enzymes for digestion
What is the function of the spleen?
produces lymphocytes and filters blood
What is the porta hepatis?
transverse fissure in the middle visceral surface of the liver that gives passage to the hepatic portal vein, hepatic artery, hepatic nerve plexus, hepatic ducts, and lymphatic vessels
Where is the gall bladder attached? What does it connect to?
- attached to inferior surface of liver- contacts duodenum, colon, and anterior abdominal wall
What occurs within the gallbladder?
receives bile produced by liver via bile ducts; bile then drains into duodenum through these ducts
Name the bile ducts. Where does each receive it’s bile?
- right and left hepatic ducts: receives bile from right and left lobes of liver- common hepatic duct: receives right and left hepatic ducts- cystic duct: connected to gallbladder- common bile duct: receives cystic and common hepatic ducts
Describe the drainage of the bile ducts.
- right/left hepatic duct drain into common hepatic duct- common hepatic duct and cystic duct drain into common bile duct- common bile duct and main pancreatic duct drain into the major duodenal papilla in descending duodenum
Name the parts of the pancreas.
- head- neck- body- tail- uncinate process (posterior to superior mesenteric artery)
True or false: The pancreas is retroperitoneal.
true
What surrounds the pancreas?
surrounded by C-shaped duodenum on the right and spleen on the left
Describe the drainage of the pancreatic ducts.
- main pancreatic duct: enters duodenum with bile duct at major duodenal papilla- accessory pancreatic duct: may enter duodenum as well 2 cm superior to major papilla (minor papilla)*pattern of pancreatic drainage is variable
What is the hilum?
area of the spleen which is not surrounded by peritoneum where the splenic branches of the splenic artery and vein enter and leave
Where does the spleen contact the diaphragm?
contacts diaphragm along ribs 9-11
What are the 3 areas of the spleen?
- gastric area- renal area- colic area
What are the paired visceral branches of the abdominal aorta?
- suprarenal arteries- renal arteries- gonadal (ovarian or testicular) arteries
What are the unpaired visceral branches of the abdominal aorta?
- celiac trunk- superior mesenteric artery- inferior mesenteric artery
What are the paired parietal branches of the abdominal aorta?
- inferior phrenic arteries- lumbar arteries
What is the unpaired parietal branch of the abdominal aorta?
median sacral artery
What does the celiac trunk branch off of? What does it supply?
- 1st major branch of the abdominal aorta- supplies liver, gallbladder, esophagus, stomach, pancreas, and spleen
What are the 3 branches of the celiac trunk?
- common hepatic artery- left gastric artery- splenic artery
What does the common hepatic artery branch off of? Where does it run?
- right branch of the celiac trunk- runs toward liver and gallbladder
What are the 2 branches of the common hepatic artery?
- proper hepatic artery- gastroduodenal artery
What is the proper hepatic artery a branch of? Where does it run?
- superior branch of common hepatic artery- runs toward the liver medial to the common bile duct and superficial to the portal vein
What does the proper hepatic artery split into?
splits into the right and left hepatic arteries which supply the right and left lobes of the liver
What is the gastroduodenal artery a branch of? Where does it run?
- inferior branch of the common hepatic artery- runs toward the junction of the stomach and duodenum
What are the branches of the gastroduodenal artery?
- superior pancreaticduodenal artery to pancreas/duodenum- right gastroepiploic artery to the greater curvature of the stomach- sends supraduodenal artery to the superior duodenum
What is the left gastric artery a branch of? Where does it run? What does it supply?
- superior branch of the celiac trunk- runs left toward the lesser curvature of the stomach- supplies stomach and esophagus (via esophageal branches)
What is the splenic artery a branch of? Where does it run? What does it supply?
- left branch of celiac trunk- runs toward the spleen- supplies pancreas and spleen