Quiz 4 - Abdominal Wall Flashcards Preview

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Flashcards in Quiz 4 - Abdominal Wall Deck (64):

abdominal wall has a ____ anterolateral portion, and a ____ posterior portion

mobile; stable


bony landmarks that define the abdomen superiorly

xiphoid process, costal margin, ribs 11 & 12


posteriorly the abdomen is supported by _____

the lumbar vertebral column


the inferior extent of the abdomen is supported by ______

superior part of the bony pelvis; includes linea terminalis


linea terminalis

marks the lateral edge of the pelvic inlet, an imaginary plane separating the abdominal cavity from the pelvic cavity


iliac crest

-the superior edge of the iliac bone
-the most superior part (posterior aspect) is at the L4 vertebral level


anterior superior iliac spine (ASIS)

-the anterior part of the iliac crest
-serves as a site of muscle attachments


iliac fossa

-the shallow area on the anteriomedial surface of the iliac bone
-origin for iliacus muscle


arcuate line

has 2 definitions;
1. a bony ridge on the ilium that forms part of the pelvic brim
2. a line that represents a transition of the layers of the rectus sheath; created when all 3 muscular layers pass anterior to the rectus abdominus, thus leaving no muscular layers posterior to the rectus muscle


pubic symphysis

-the joint b/w the two pelvic bones anteriorly
-comprised of fibrocartilage


pubic crest

-the flat area on the superior surface of the pubic bones
-site of muscle attachments


pubic tubercle

-a rounded elevation on the superior ramus of the pubis
-attachment site for inguinal ligament


pectineal line (pecten pubis)

-a ridge on the pubis that forms part of the pelvic brim
-continuous with the arcuate line of the ilium
**named differenty because they exist on two diff lines (ilium vs. pubis)


3 bones that make up bony pelvis

1. ilium
2. ischium
3. pubis


pelvic brim

-the sharp bony margin that separates the abdominal cavity from the true pelvic cavity, although there is no physical barrier at this location
-the portion of the pelvic brim on the pelvic bone is called the linea terminalis, comprised of the pubic crest and pectineal line on the pubis, and the arcuate line on the ilium


pelvic inlet

-similar to linea terminalis
-also includes the sacral contribution to the brim and the pubic symphysis
-structures that comprise the pelvic inlet are: sacral promontory and ala (wings) of the sacrum, arcuate line, pectineal line, pubic crest, and pubic symphysis.


four quadrants of abdominal cavity

1. RUQ
2. RLQ
3. LUQ
4. LLQ

*Separated vertically by median plane and horizontally by transumbilical plane


epigastric area

superior to the umbilicus


periumbilical area

around umbilicus


suprapubic area

inferior to the umbilicus and superior to the pubic bone


major surface landmark on the abdomen

-umbilicus; found at L3/L4 intervertebral disc.
-T10 dermatome is also found at this location

(in thin individuals, the costal margin is also very prominent, and the xiphoid process can be felt)


linea alba

-midline tendinous sheath, visible as a groove down the center of the abdomen


semilunar line

-marks the lateral border of the rectus sheath


inguinal ligament

-forms the boundary between the abdominal wall and thigh


McBurney's point

-found 2/3 of the way along a line drawn from the umbilicus to the right ASIS
-marks the position of the cecum and appendix
-tenderness/pain here is indicative of appendicitis


2 layers of superficial fascia in the lower portion of the abdomen

1. superficial fatty layer (Camper's fascia)
2. deep membranous layer (Scarpa's fascia)

order: skin --> Camper's --> Scarpa's --> deep fascia


1 layer of superficial fascia in the upper abdomen

1. superficial fascia

order: skin --> superficial fascia --> deep fascia


where does Scarpa's fascia "end" ?

-lateral to the perineal region, Scarpa's fascia doesn't extend into the thigh, but fuses with the deep fascia of the thigh (fascia lata) that is continuous with the deep fascia of the abdomen

**important b/c if there is fluid deep to Scarpa's fascia, it can pass into the perineum but not the thigh.


___ major muscles comprise the abdominal wall



the three "layered" or flank muscles

1. external oblique
2. internal oblique
3. transversus abdominis

-have both muscular and aponeurotic parts
-their aponeuroses contribute to a sheath around the fourth muscle, the rectus abdominis


external oblique

-continuation of the external intercostal muscle (only without any ribs)
-fibers run "hands in the pockets"
-tendon is broad and flat, thus it is aponeurosis


the aponeurosis of the right external oblique blends with that of the left external oblique at the _____

linea alba


inferior edge of the external oblique

-turns in on itself as it attaches to the ASIS and pubic tubercle
-this edge is called the inguinal ligament


internal oblique

-fibers orientated at 90* to that of the external oblique
-originates from the lateral 2/3 of the inguinal ligament


transversus abdominis

-fibers oriented in the transverse plane
-originates from the lateral 1/3 of the inguinal ligament


portions of the internal oblique and transversus abdominis arise from the ____

-inguinal ligament (which is part of the external oblique)
-their origins make it such that there is a larger "gap" between the inguinal ligament and the transversus abdominis, than there is between the inguinal ligament and the internal oblique.


rectus abdominis

-long, straight muscle in the central portion of the abdominal wall; enclosed within a sheath that is comprised of the aponeuroses of the layered muscles, which meet in the midline at the linea alba

-medial border: linea alba
-lateral border: rectus sheath

-superior to arcuate line: external and 1/2 internal anterior to rectus, and 1/2 internal and transversus posterior to rectus
-inferior to arcuate line: external, internal, and transversus all anterior to rectus; transversalis fascia posterior

**the abrupt change in the location of the internal oblique and transversus abdominis aponeuroses is what forms the arcuate line; in some individuals the change is more gradual though so the line isn't always too obvious


transversalis fascia

-deep to the rectus abdominis and transversus abdominis muscles
-overlies the parietal peritoneum, the serous membrane that lines the abdominal cavity


between the transversalis fascia and the peritoneum...

is a variable amount of fat and loose CT called extraperitoneal fascia; surgeons divide this further into preperitoneal fascia (anterior part of body) and retroperitoneal fascia (posterior part of the body)


functions of the abdominal muscles

1. support and protect abdominal viscera
2. compress the abdominal contents to increase intra-abdominal pressure (necessary for coughing, vomiting, singing, defecation, micturation, and parturition)
3. flex the trunk (except for transversus abdominis)
4. rotate the trunk (obliques only)
5. provide support for lower back
6. contract during expiration and relax during inspiration


innervation of the abdominal wall (skin and muscles) is provided by:

-lower intercostal nerves (ventral rami of T7-T11),
-subcostal nerve (ventral ramus of T12)
-ventral ramus of L1 (branches into iliohypogastric and iliolingual nerves)


T7 dermatome

-just inferior to xiphoid


T10 dermatome

-at umbilicus


T12 dermatome

-at suprapubic region


L1 dermatome

-upper medial thigh and genitalia


abdominal aorta bifurcates into the ______

common iliac arteries


what happens to the common iliac arteries on each side?

-an internal iliac artery is given off that descends into the pelvis, and the "continuation" of the common iliac is now called the external iliac artery


when the external iliac artery travels into the thigh, it changes names to the ____

femoral artery


blood supply of abdominal wall comes from 2 major sources

1. descending aorta (posterior intercostal and subcostal)
2. epigastric arteries


where do the posterior intercostal and subcostal branches of the descending aorta travel?

-around the abdominal wall between the internal oblique and transverse abdominis muscles
-primarily supply the layered muscles! (E, I, T)


2 sets of veins that drain the abdominal wall

1. superficial veins: drain the superficial fascia
2. deep veins: drain muscles and deep tissue

*communications exist between the two sets of veins


superficial (thoracoepigastric) veins

-drain superficial fascia
-form longitudinal venous channels in the superficial fascia
-channels drain superiorly into veins of the axilla
-drain inferiorly into veins of the groin
-drain medially into veins around the umbilicus


deep veins

-have the same names as the arteries
-drain superiorly into subclavian vein
-drain inferiorly into external iliac and femoral veins
-drain posteriorly into IVC and azygos system


lymphatics of the abdominal wall generally follow the ___



lymphatics from superficial tissues in the upper half of the abdomen drain to _____

nodes in the axilla (axillary nodes)


lymphatics from superficial tissues in the lower half of the abdomen drain to ______

nodes in the groin region (superficial inguinal nodes)


lymphatics from deep structures drain to lymph nodes located ______

-along major vessels (e.g. lumbar nodes adjacent to the aorta)
-drain into cisterna chyli (a lymphatic "sac" that collects lymph from the abdomen) and subsequently into the thoracic duct


falciform ligament

-oxygenated blood from the placenta enters the fetus via the umbilical vein
-as this veins is traveling towards the liver from the umbilicus, it becomes enclosed by a fold of parietal peritoneum called the falciform ligament


deoxygenated blood returns to the placenta via ___

-umbilical arteries
-these arise from the internal iliac arteries, travel superiorly on the internal surface of the abdominal wall, and exit the abdominal cavity via the umbilical cord


fibrous remnant of the umbilical vein + the fold of peritoneum

= the ligamentum teres hepatis (round ligament of the liver)


fibrous remnants of the umbilical arteries

-medial umbilical ligaments
-produced folds in the peritoneum known as the medial umbilical folds



-contained by the umbilical cord
-blind-ended sac, which connected to the rudimentary bladder
-eventually, the lumen of the allantois obliterates and its remnant is the urachus; it produces the median umbilical fold in the peritoneum


inferior epigastric vessels

-enter the rectus sheath on the deep surface of the rectus abdominis muscle
-before entering the rectus sheath, these vessels travel superiorly between the transversalis fascia and peritoneum, producing folds in the peritoneum known as the lateral umbilical folds


what do you use to find the level of L3-L4 intervertebral disc?

iliac crest; even tho the umbilicus is also at L3-L4, it's hard to draw a line from the stomach to the back, especially with the patient bent over