Part II. Anterolateral abdominal wall pg 33-39 Flashcards
The abdominal cavity is located between what two anatomical landmarks?
Thoracic diaphragm and pelvic inlet/superior pelvic aperture
The abdominopelvic cavity is located between what two anatomical landmarks?
Thoracic diaphragm and Pelvic diaphragm
Are the abdominal and pelvic cavities continuous with each other?
Yes
What landmark denotes the transition between the abdominal and pelvic cavity
Superior pelvic aperture/pelvic inlet
What lines the abdominal cavity and viscera?
Peritoneum
The potential space between the peritoneal layers of the abdominal cavity is called what?
Peritoneal cavity
What are the planes that delineate the abdomen into 9 regions, as clinicians often do?
- subcostal plane
- transtubercular plane
- midclavicular plane (x2)
Where is the subcostal plane?
It is the horizontal plane between and inferior to the 10th costal cartilages
Where is the transtubercular plane?
Horizontal plane through iliac tubercles and L5 vertebrae.
Where are the midclavicular planes?
Vertical planes through the midpoint of each clavicle to ipsilateral midinquinal region.
What re the 9 regions of the abdominal cavity?
- Epigastric region bordered on either side by R/L hypochondriac region
- Umbilical region bordered on either side by R/L lateral region
- Pubic region bordered on either side by R/L inguinal region
More general divisions of the abdominal cavity are delineated by only 2 planes. What are they?
Transumbilical plane
Median plane
Where is the transumbilical plane?
Horizontal plane through umbilicus and L3-L4 IVD
Where is the median plane?
Vertical plane through the midpoint (midsagittal) of the body
Using the more general divisions of the abdomen (using 2 lines), what are the 4 regions of the abdomen?
- R/L Upper Quadrants
- R/L Lower Quadrants
Contents in RIGHT upper quadrant of the abdomen:
- Liver (right lobe)
- Gall bladder
- Stomach (pylorus)
- Duodenum
- Pancreas (head)
- R Suprarenal gland
- R Kidney
- R Colic (hepatic) flexure
- Ascending colon (superior part)
- Transverse colon (right half)
Contents in LEFT upper quadrant of the abdomen:
- Liver (left lobe)
- Spleen
- Stomach
- Jejunum and proximal Ileum
- Pancreas (body and tail)
- L Suprarenal gland
- L Kidney
- L Colic (splenic) flexure
- Transverse colon (left half)
- Descending colon (superior part)
Contents in RIGHT lower quadrant of the abdomen:
- Cecum
- Appendix
- Ascending colon (inferior part)
- Ileum (most of it)
- R Ovary
- R Uterine tube
- R Ureter
- R Spermatic Cord
- Uterus (if enlarged)
- Urinary bladder (if very full)
Contents in LEFT lower quadrant of the abdomen:
- Descending colon (inferior part)
- Sigmoid colon
- L Ovary
- L Uterine tube
- L Ureter
- L Spermatic cord
- Uterus (if enlarged)
- Urinary bladder (if very full)
Where is the anterolateral abdominal wall located?
- Inferior to ribs 7-10 costal cartilages and xiphoid process
- superior to inguinal ligament and pelvic bones
What are the two superficial fascia layers of the anterolateral abdominal wall?
- Camper’s fascia (superficial fatty layer)
- scarpa’s fascia (deep membranous layer
What is Camper’s fascia equivalent to histologically?
Hypodermis
Describe Scarpa’s fascia histologically.
It is a thin layer of Dense irregular CT with a thin layer of loose CT separating it from the deep fascia
What is the functional significance of the thin layers of loose CT that separates Scarpa’s fascia from the deep fascia?
It allows for independent movement of superficial and deep fascia
What is the dense irregular CT they surround the abdominal muscles and their anoneuroses?
Deep fascia (investing fascia)
What is the loose CT located between muscles/aponeuroses and parietal peritoneum?
Endoabdominal fascia
Endoabdominal fascia is analogous to ____________ in the thorax and continuous with _________ in the pelvis.
Endothoracic fascia: endopelvic fascia
What fascia provides a potential surgical dissection plane for extraperitoneal and/or retroperitoneal organs
Endoabdominal fascia
What are the 5 muscles of the anterolateral abdominal wall?
- external oblique m.
- internal oblique m.
- transversus abdominis m.
- rectus abdominis m.
- pyramidalis m.
Orientation of the muscle fibers of external oblique muscles?
Inferioanteriorly (like external intercostal)
Origin of external oblique
Ribs 5-12
Insertion of external oblique muscle
- linea alba
- pubic tubercle
- anterior 1-2 of iliac crest
The aponeurosis that begins approximately at the midclavicular line
Linea semilunaris
The inferior margin of the linea alba thickens and rolls to form what?
Inguinal ligament
The inguinal ligament extends from where to where?
ASIS to pubic tubercle
The inguinal ligament is the anterosuperior attachment point for what?
Fascia lata
What innervates the external obliques and rectus abdominis muscle?
- T7-11 thoracoabdominal nerves
- subcostal nerve (T12)
Note: internal oblique and transversus are innervated by those nerves as well as iliohypogastric nerve and ilioinguinal nerve.
Orientation of the muscle fibers of the internal oblique
Fan out anteromedially from ASIS
What is the origin of internal oblique muscles?
- Thoracolumbar fascia
- anterior 2/3 of iliac crest - inguinal ligament
What is the insertion of the internal oblique muscles?
- Ribs 10-12
- linea alba
- pectin pubis via conjoint tendon