86 terms

Anatomy of the Abdominopelvic Cavity

What are the two parts of the abdominopelvic cavity?
abdominal cavity and pelvic cavity
Boundaries of the abdominal cavity?
diaphragm to pelvic inlet (continuous with pelvic cavity)
What organs are in the abdominal cavity?
digestive organs, spleen, kidneys, majority of ureters
What planes separate the epigastric regions?
2 horizontal- subcostal and transtubercular; 2 vertical- midclavicular on each side
What planes separate the abdominal quadrants?
horizontal=transumbilical, vertical=median
What are the divisions of the abdominal wall?
anterior, posterior, right and left lateral (flanks)
What are the boundaries of the anterolateral abdominal wall?
extends from the thoracic cage to the pelvis; superior boundary= costal cartilages 7-10 and xiphoid process, inferiorly=inguinal ligament and pelvic bones
Majority of the anterolateral wall is ?
List all components of the anterolateral abdominal wall
skin, superficial fascia, muscles, deep fascia, endabdominal fascia/fat, parietal peritoneum
What are the two layers of superfiscial fascia in the abdominal wall?
Camper's fascia=fatty, Scarpa's fascia= membranous
What are the four muscles of the anterolateral abdominal wall?
external oblique, internal oblique, transversus abdominis, rectus abdominis
Origin and insertion of the external oblique
external surface of 5-12 ribs ---> lina alba, pubic tubercle, and anterior 1/2 of iliac crest
5 actions of the external oblique
1. compress/support abdominal viscera
2. laterally flex trunk
3. rotate trunk
4. pelvis fixed- flex trunk
5. thorax fixed- tilt pelvis posteriorly
What is the common innervation for all anterolateral abdominal wall muscles?
thoracoabdominal nerves (T6-T11)
Origina and insertion of internal oblique
thoracolumbar fascia, anterior 2/3 of iliac crest, later 1/2 of inguinal ligament---> inferior borders of 10-12 ribs and linea alba
3 actions of the internal oblique
1. compress and support abdominal viscera
2. laterally flex trunk
3. rotate trunk
origin and insertion of the rectus abdominis
pubic symphysis and pubic crest ---> xiphoid process and 5-7 costal cartilages
Actions of the rectus abdominis
1. compress abdominal viscera
2. flex trunk (lumbar vertebrae)
What is the common action of the anterolateral abdominal wall muscles?
compress and support abdominal viscera
What muscles laterally flex the trunk?
External oblique, internal oblique
origin and insertion of the transversus abdominis
7-12 costal cartilages, iliac crest, inguinal ligament, thoracolumbar fascia ---> pubic crest and linea alba
Action of the transversus abdominis
compress and support abdominal viscera
What muscles comprise the posterior abdominal wall?
psoas major, iliacus, and quadratus lumborum
Psoas major origins/ insertions
travsverse processes of L1-L5 and vertebral bodies of T12-L4 ---> lesser trochanter of the femur
Psoas major actions
1. hip flexion
2. lateral rotation
NI psoas major
ventral rami
Iliacus origin/insertion
iliac fossa ---> lesser trochanter of the femur
Actions of iliacus
1. hip flexion
2. lateral rotation
NI iliacus
femoral nerve
Quadratus lumborum origin/insertion
iliac crest ---> 12th rib and lumbar transverse processes
Quadratus lumborum actions
1. extends vertebral column
2. laterally flexes vertebral column
NI quadratus lumborum
vertebral branches of T12 and L1-L4 nerves
Where is the parietal peritoneum?
lines the internal surface of the abdominopelvic wall
Where is the visceral peritoneum?
invests the viscera such as the stomach and spleen
Where are the peritoneum and viscera located?
abdominal cavity
What is in the peritoneal cavity?
No organs- just some thin fluid
What are intraperitoneal organs?
Not organs inside the peritoneal cavity- just means that they're surrounded in visceral peritoneum (stomach, spleen, liver, etc)
What are extraperitoneal organs?
organs that lie posterior to the peritoneum- usually covered by the peritoneum on just one surface (i.e. pancrease, kidneys)
peritoneum that connects organs to posterior abdominal wall
double-layered extension of the peritoneum; passes from stomach to adjacent organs or abdominal wall (collect fat)
lesser omentum
descriptive term for the peritoneum from the lesser curvature of the stomach and duodenum to the liver
greater omentum
hangs like an apron from the greater curvature of the stomach and proximal duodenum; fold abck and attaches to the transverse colon and mesentery
What are the dimensions of the terminal esophagus?
25 cm long, 2 cm diameter
What is the function of the termnal esophagus?
conveys food from the pharynx to the stomach
What comprises the terminal esophagus?
Superior 1/3= skeletal muscle, distal 1/3=smooth muscle, middle 1/3=mixed
What is the widest and most fixed part of the small intestine? How long is it?
Duodenum- 10 inches
Where do most processes of digestion occur?
stomach and duodenum
Where does the pancreas dump its enzymes?
duodenum- makes this a major site for chemical digestion
Where is the jejunum?
middle portion of small intestine; primarily in the upper quadrants
Where is the ileum?
end of small intestine; primarily in the lower quadrants
How long are the jejunum and ileum combined?
10 ft
What structures comprise the large intestine?
cecum, appendix, colon, rectum, anal canal
What is the largest lymphatic organ?
Spleen quadrant?
True or false: the spleen descends inferior to the costal region
usually false
Can the spleen regenerate?
What conditions cause splenomegaly?
mono and leukemia
What are the functions of the pancreas?
exocrine: secrete pancreatic juice into the duodenum; endocrine: secrete glucagon and insulin from the islets of Langerhans into blood
Where is the pancreas located?
Describe the structure of the liver
contains functionally independent right and left lobes separated by a falciform ligament. The right lobe includes caudate and quadrate lobes. URQ and ULQ
Where is the gall baldder?
visceral surface of the liver; URQ
What part of the gall bladder projects from the inferior border of the liver?
What part of the gall bladder contacts the visceral surface of the liver?
What part of the gall bladder is directed toward the cystic duct?
neck (narrow and tapered)
What is the function of the cystic duct?
leads from the gall bladder to the bile duct to drain bile
What forms the bile duct and what is its purpose?
union of cystic and hepatic ducts; drains bile into the duodenum
Where are the kidneys?
They lie on the posterior abdominal wall (flanks)
Function of the kidneys?
control plasma volume and convey waste from blood producing urine for elimination via ureters
Which kidney sits lower?
the right
What is the renal hilum?
medial margin of each kidney where vessels enter and exit
What are ureters?
muscular ducts (25-30 cm in length) that carry urine from the kidneys to the urinary bladder
What lies at the superior end of the ureters?
renal pelvis
Describe the path of renal drainage
papillary duct in renal pyramid--> minor calyx --> major calyx --> renal pelvis --> ureter --> urinary bladder
What structures lie in the inguinal region? (males)
inguinal canal, spermatic cord, scrotum, epidydymis, testes
Describe the location of the inguinal canal
inferior to the anterolateral abdominal wall, parallel and just superior to the inguinal ligament
Main occupants of the inguinal canal
vessels to lower extremity; spermatic cord in males, round ligament of the uterus in females
What is the function of the spermatic cord?
suspends testis in the scrotum
name the three significant components of the spermatic cord and their functions
1. ductus deferens: conveys sperm from the epididymis to the ejaculatory duct
2. cremaster muscle: draws testis superiorly, especially when it is cold
3. testicular artery: supplies the testis and epididymis
What two layers comprise the scrotum?
heavily pigmented skin and the dartos muscle
Where is the epididymis?
posterior surface of the testes
Describe the parts of the epididymis
head: formed by coiled ends of efferent ductules
body: consists of convoluted duct of epididymis
tail: continuous with the ductus deferens
What coveres the testes?
tough fibrous coat called the tunica albuginea
Where is sperm formed?
seminiferous tubules in the testis
What are the pelvic cavity viscera? (females)
urinary bladder, uterus, uterine tubes, ovaries
What are the four parts of the uterus?
body, fundus, isthmus, neck (cervix)
What lead from the uterus to the ovaries
uterine tubes (formerly fallopian tubes)