Lecture 10 (abdomen) Flashcards
What are the 4 main parts of the abdomen?
1) Abdominal wall
2) Abdominal cavity
3) Peritoneal cavity
4) Viscera
List all the parts of the abdomen
1) Abdominal cavity
2) Anterolateral abdominal wall
3) Peritoneum and peritoneal cavity
4) Abdominal viscera
5) Diaphragm
6) Posterior abdominal wall
7) Neurologic innervation
What does the abdominal viscera include? (4 groups of things)
1) GI: Esophagus, stomach, small and large intestine
2) Spleen, pancreas
3) Liver, biliary system, portal venous system
4) Kidneys, ureters, suprarenal (adrenal) glands
What part of the abdomen does the diaphragm make up?
Superior portion
What innervates the viscera pre-splenic flexure?
Vagus nerve
What does the pelvic brim separate?
Greater pelvis of abdominal cavity and lesser pelvis of pelvic cavity
What is the superior part of the ilium bones called?
Iliac crest
1) What is the most medial anterior part of the pelvis called?
2) What is superior and slightly lateral to this?
1) Symphysis
2) Pubic tubercle
What two parts of the abdominal wall are made up of the same muscles (for the most part)
Anterior and lateral (hence the term anterolateral)
The abdomen has ____ quadrants and ____ regions
4 quadrants; 9 regions
What regions are lateral to the epigastric (most superior and medial) region of the abdomen?
Right and left hypochondriac regions
What regions are lateral to the umbilical (middle) region of the abdomen?
Right and left lumbar regions
What regions are lateral to the hypogastric (most inferior and medial) region of the abdomen?
Left and right iliac regions
How far inferiorly does the abdominal cavity go?
Into the false pelvis
What is the importance of the linea alba?
If you cut vertically down it you won’t cut through muscle.
(goes from xyphoid process, through umbilicus, to pubic symphysis)
What are the layers of the anterolateral abdominal wall? (from superficial to deep)
1) Skin
2) Superficial fascia (SQ)
3) Investing (deep) fascia
4) Endo-abdominal fascia
5) Extraperitoneal fat
6) Parietal peritoneum
What covers external aspects of 3 muscle layers of abdominal wall and their aponeurosis?
Investing (deep) fascia
What are the two layers of the superficial fascia of the anterolateral abdominal wall? Describe each
1) Camper fascia: fatty layer
2) Scarpa fascia: deep membranous layer
Where is the superficial fascia of the abdomen found? How many layers does it have?
Inferior to umbilicus; 2 layers
Describe the thickness of the endo-abdominal fascia and what it lines
Variable thickness, lines the internal aspect of the abdominal wall (named based on the muscle/aponeurosis it covers)
What does the parietal peritoneum line?
Abdominal cavity
1) What is closed as separate layer during abdominal wall closure?
2) Describe this structure
1) Scarpa fascia closed
2) Fibrous and has holding power
What is inferior to the umbilicus, separated into 2 layers?
SQ tissue (superficial fascia)
1) What is Camper’s fascia?
2) What is it made of?
1) Is the superficial fatty layer of the superficial fascia (SQ) of the abdominal wall.
2) Loose areolar tissue.
1) What is Scarpa’s fascia?
2) Where is it found?
3) What is it important in? Why?*
1) The deep membranous layer of the superficialfascia(SQ) of the abdomen wall.
2) Deep to theFasciaof Camper and superficial to the external oblique muscle.
3) Closing the abdominal cavity, bc it has the holding strength (vs the fatty Camper’s fascia)
Where in the abdomen is there a potential space for fluid/infection to spread?
Between scarpa fascia and deep fascia covering abdominal muscles
What does the Scarpa fascia attach and fuse to?
Attaches to pubic bone and fuses with deep fascia of thigh
List the 5 paired muscles of the abdominal wall
-3 flat muscles: External oblique, internal oblique, transversus abdominis mm.
-2 vertical muscles: Rectus abdominis, pyramidalis mm.
What forms the aponeurosis anterior?
Flat muscle
1) What encloses the rectus abdominis?
2) What does enclosing structure then form at the midline?
1) Rectus sheath
2) Linea alba
Where does the linea alba run from and to?
Xyphoid to pubic symphysis
EO (external oblique) muscle interdigitates with ________________ muscle fibers on costal surface
serratus anterior
What are the 3 oblique muscles?
External oblique, internal oblique, transversus abdominis mm. (EO, IO, TA)
What are the anterolateral abdominal muscles? (6)
1) Obliques: EO, IO, TA
2) Rectus: rectus sheath, linea alba
3) Pyramidalis
1) What does the rectus abdominis muscle look like?
2) What encloses it?
3) What is its unique feature? Where? What is each attached to?
1) Long vertical straplike muscle
2) Rectus sheath
3) Tendinous intersections:
-Typically, at level of xyphoid, umbilicus and halfway between
-Each intersection firmly attached to overlying rectus sheath
In what muscle can tendonous intersections be found?
Rectus abdominis muscle
What muscle is absent in about 20% of patients?
Pyramidalis muscle
1) What muscle has tendinous intersections?
2) Where are they?
3) What are these intersections attached to?
1) Rectus abdominis
2) At level of xyphoid, umbilicus, and halfway between
3) Overlying rectus sheath
1) What encloses the pyramidalis muscle? Where is it?
2) What does it arise from and insert into?
3) When does it tense?
1) Rectus sheath; pyramidalis is anterior to inferior part of rectus m.
2) Arises from pubic crest, inserts into linea alba
3) During Valsalva maneuver
What tenses during the Valsalva maneuver?
Pyramidalis muscle
What is the aponeurosis of flat abdominal muscles?
Rectus sheath
What are the 3 sections of the rectus sheath?
1) Superior to arcuate line
2) Arcuate line
3) Inferior to arcuate line
Superior to the arcuate line:
1) What makes up the anterior rectus?
2) What makes up the posterior rectus?
1) Anterior: EO fascia + anterior lamina of IO
2) Posterior: Posterior lamina of IO + TA fascia
(eo is external oblique, io is internal oblique, TA is transversus abdominis
1) Where is the arcuate line?
2) What does it demarcate?
1) 1/3 distance from umbilicus to pubic symphysis
2) The transition between the posterior rectus sheath covering the superior ¾ of the rectus abdominis proximally, and the transversalis fascia covering the inferior ¼
Inferior to arcuate line:
1) What makes up the anterior rectus?
2) What makes up the posterior rectus?
1) Anterior: aponeurosis of all 3 muscles
2) Posterior: transversalis fascia (endoabdominal fascia)
What makes up the posterior rectus sheath superior to the arcuate line?
Posterior lamina of IO and fascia of TA + Transversalis fascia (endoabomial fascia)
What part of the posterior rectus sheath continues to inferiorly to the arcuate line?
Only TF (transversalis fascia)
The fusion of abdominal muscle fascias at the midline is called what?
Linea alba
At the arcuate line, what pierce the posterior rectus sheath to provide blood to rectus muscle?
Inferior epigastric arteries and veins
What do the inferior epigastric arteries and veins do?
At arcuate line they pierce the posterior rectus sheath to provide blood to rectus muscle
1) What 2 muscles are contained within the rectus sheath?
2) What vessels are enclosed within it?
3) What nerves are enclosed within it?
1) Rectus abdominis m. and pyramidalis m.
2) Anastomosing inferior and superior epigastric vessels, lymphatics
3) Thoraco-abdominal and subcostal nerves (anterior rami of distal T7-12 spinal nerves)
How many peritoneal folds pass toward the umbilicus on the internal surface of the antero-lateral abdominal wall?
5
What are the 5 peritoneal folds that pass toward the umbilicus?
1) Median umbilical fold (ligament) (remnant of urachus, which is the apex of fetal bladder to umbilicus)
2&3) R & L medial umbilical fold (ligament) (umbilical arteries remnant)
4&5) R & L lateral umbilical fold over Inferior Epigastric a
What is the urachus? What is a remnant of it?
The apex of fetal bladder to umbilicus; median umbilical fold (ligament)
What is the remnant of the umbilical arteries?
Right and left medial umbilical folds (ligaments)
The right and left lateral umbilical folds are over what?
Inferior epigastric arteries
1) Where are indirect inguinal hernias found?
2) Where are direct inguinal hernias (straight through inguinal triangle) found?
1) Lateral inguinal fossa
2) Medial inguinal fossa
Theurachusis a fibrous remnant of the ____________, a canal that drains the __________ bladder of the fetus that joins and runs within the umbilical cord.
allantois; urinary
Where is the urachus found?
Within the median umbilical fold (ligament)
Name 3 things that can go wrong with the urachus
1) Urachal cyst
2) Urachal sinus
3) Patent urachus
