Anterolateral Abdominal Wall, Inguinal Region and Peritoneum Flashcards
What is the space bounded by the abdominal walls, diaphragm, and pelvis?
abdominal cavity
What does the abdominal cavity form the major part of?
abdominopelvic cavity
What is enclosed anterolaterally by dynamic musculo-aponeurotic abdominal walls?
abdominal cavity
What is separated superiorly from the thoracic cavity and posteriorly from the posterior thoracic vertebrae by the diaphragm?
abdominal cavity
What is under the thoracic cage superiorly extending to the 4th intercostal space?
abdominal cavity
What is continuous inferiorly with the pelvic cavity and is lined with peritoneum (a serous membrane)?
abdominal cavity
Where is the location of most of the digestive organs, spleen, kidneys, and ureters for most of their course?
abdominal cavity
What are the 4 quadrants of the abdomen?
- right upper quadrant
- right lower quadrant
- left upper quadrant
- left lower quadrant
What are the 9 abdominal regions?
- right hypochondriac
- epigastric
- left hypochondriac
- right lateral
- umbilical
- left lateral
- right inguinal
- pubic
- left inguinal
Where is the subcostal plane found in relation to the costal cartilages?
10th costal cartilage
What regions are found in the subcostal plane of the abdomen?
- epigastric (E)
- umbilical (U)
- pubic (P)
- hypochondriac (H)
- lumbar (L)
- inguinal (I)
Where can you find the transtubercular plane?
between the iliac tubercles and L5 vertebra
Where can you find the transumbilical plane?
around the umbilicus and IVD L3-L4
Where are these organs found?
- liver (right lobe)
- gallbladder
- stomach (pylorus)
- duodenum
- ascending colon (superior part)
- transverse colon (right half)
- pancreas (head)
- right suprarenal gland
- right colic flexure
- right kidney
right upper quandrant
Where are these organs found?
- liver (left lobe)
- spleen
- stomach
- jejunum and proximal ileum
- pancreas (body and tail)
- left kidney
- left suprarenal gland
- left colic flexure
- transverse colon (left half)
- descending colon (superior part)
left upper quadrant
Where are these organs found?
- cecum
- appendix
- most of the ileum
- ascending colon (inferior part)
- right ovary
- right uterine tube
- right ureter (abdominal part)
- right spermatic cord (abdominal part)
- uterus (if enlarged)
- urinary bladder (if very full)
right lower quadrant
Where are these organs found?
- sigmoid colon
- descending colon (inferior part)
- left ovary
- left uterine tube
- left ureter (abdominal part)
- left spermatic cord (abdominal part)
- uterus (if enlarged)
- urinary bladder (if very full)
left lower quadrant
Thoraco-abdominal nerves run from what levels?
T7-T11 + T12 (subcostal)
What vertebral level dermatome supplied the nipple?
T4
What vertebral level dermatome supplied the xiphoid process?
T7
What vertebral level dermatome supplied the umbilicus?
T10
What vertebral level dermatome supplied the groin/inguinal region?
L1
The dermatomes of major landmarks follows what rule?
the rule of “3”
What supplies sensory innervation to the skin on the anterior surface of the external genitalia and medial surface of the thigh after providing motor innervation to the anterolateral abdominal wall?
ilioinguinal nerve (L1)
What are the two layers of fascia of the abdominal wall?
- superficial fascia - fatty layer (Camper’s fascia)
- superficial fascia - membranous layer (Scarpa’s fascia)
What are the layers of the thorax from superficial to deep?
- skin/integument
- superficial fascia
- deep fascia
- muscle/bone
- endothoracic fascia
- cavity (serous sac and membranes)
What are the layers of the abdominal cavity from superficial to deep?
- skin/integument
- superficial fascia
**fatty: Camper’s fascia
**membranous: Scarpa’s fascia - deep fascia (invests muscles)
- musculotendinous
- transversalis fascia (endoabdominal fascia)
- cavity (serous sac and membranes)
What is Scarpa’s fascia only present between?
the umbilicus and inguinal region
What is the name for the parietal fascia of the thorax?
endothoracic fascia
What is the name for the parietal fascia of the abdomen?
endoabdominal fascia (transversalis fascia deep to the transversus abdominis muscles)
What is this describing:
- superficial thigh fascia
- pubis and perineum superficial perineal fascia
Fatty: Camper’s fascia
What is this describing:
- fascia lata distal to inguinal region
- fuses linea alba and public symphysis
Membranous: Scarpa’s fascia
What covers the abdominal muscles and spermatic cord?
deep fascia of the abdomen
What creates a “gutter” for the spermatic cord?
aponeurosis of the external oblique muscles
What are the 2 flat muscles that make up the anterolateral abdominal muscles?
- external oblique
- internal oblique
- transversus abdominis
What are the actions of the anterolateral abdominal muscles?
lateral flexion and rotation of the vertebral column; compression of abdominal content
What contributes to the anterior layer of the rectus sheath?
aponeurosis of external oblique
What contributes to the anterior and posterior layers of the rectus sheath?
aponeurosis of internal oblique
What contributes to the posterior layer of the rectus sheath?
aponeurosis of transversus abdominis
The external oblique muscle originates on what?
5th - 12th ribs
What does the external oblique muscle attach to?
- linea alba
- iliac crest
- pubic tubercle
What does the internal oblique muscle originate on?
- thoracolumbar fascia
- iliac crest
- CT-deep to inguinal ligament
What does the internal oblique muscle attach to?
- 10th-12th ribs
- linea alba
- conjoint tendon
What is the origination of the transverus abdominis?
- 7th-12th costal cartilage
- thoracolumbar fascia
- iliac crest
- CT-deep to inguinal ligament
What does the transversus abdominis muscle attach to?
- linea alba
- pubic crest (conjoint tendon)
What are the two vertical muscles in the anterolateral body wall?
rectus abdominis
What does the rectus abdominal muscle original on?
pubic symphysis and crest
What does the rectus abdominis muscle attach to?
xyphoid cartilage
What are the actions of the rectus abdominis?
- flex torso
- rotate torso
- compress and support viscera
What is the innervation of the external oblique muscle?
thoraco-abdominal and subcostal nerves (T7-T12)
What is the innervation of the internal oblique and transversus abdominis?
- thoraco-abdominal (T7-T11)
- subcostal and first lumbar nerve
What is the innervation of the rectus abdominis muscle?
thoraco-abdominal and subcostal nerves (T7-T12)
What are the actions of the external and internal oblique muscles?
- compresses and supports abdominal viscera
- flex and rotate trunk
What are the actions of the transversus abdominis muscle?
compresses and supports abdominal viscera
What are the actions of the rectus abdominis muscle?
- flexes trunk
- compresses abdominal viscera
- stabilizes and controls tilt of pelvis
What are the functions of the anterior abdominal wall?
- protection of abdominal organs
- postural support
- childbirth
- defecation and urination
- breathing
- coughing and singing
What forms a strong, expandable support for the abdominal region?
the muscles of the anterolateral abdominal wall
What protects the abdominal viscera from injury?
the muscles of the anterolateral abdominal wall
What compresses the abdominal viscera to maintain or increase intra-abdominal pressure?
the muscles of the anterolateral abdominal wall
What does compressing the abdominal viscera and increasing intra-abdominal pressure do?
- elevates the relaxed diaphragm to expel air (respiration, coughing, voluntary burping)
What produces the force required for defecation, micturition, vomiting, and parturition?
the muscles of the anterolateral abdominal wall
What produces anterior and lateral flexion and rotation of the trunk and help maintain posture?
the muscles of the anterolateral abdominal wall
What is the most inferior part of the external oblique aponeurosis?
inguinal ligament
What is the thickened inferior margin of the transversalis fascia?
iliopubic tract
The inguinal ligament and iliopubic tract extend from what?
anterior superior iliac spine to the pubic tubercle
Most of the fibers of the inguinal ligament insert into the pubic tubercle, but some fibers:
- attach to superior ramus of the pubis lateral to the pubic tubercle as the lacunar ligament & continue to run along the pectin pubis as the pectineal ligament
- arch superiorly to blend with the contralateral external oblique aponeurosis as the reflected inguinal ligament
The internal oblique aponeurosis superior to T10 has how many layers?
2 layers
- anterior sheath
- posterior sheath
Inferior to T10, what is missing posterior to the rectus abdominis muscle?
no rectus sheath posterior
Inferior to T10, what is in direct contact with the transversalis fascia since there is no aponeurosis on the posterior aspect of the rectus abdominis muscle?
rectus abdominis muscles
What is an area of demarcation visible from the peritoneal surface of the abdominal wall residing one-third the distance between the umbilicus and the pubis?
arcuate line
What is a good landmark to see the epigastric muscles?
arcuate line
What are the borders of the Hesselbach’s triangle?
- lateral border of rectus abdominis muscle (medial)
- inferior epigastric vessels (lateral)
- inguinal ligament (inferior)
What type of hernia goes through the deep inguinal ring?
indirect hernia
What type of hernia goes through hesselbach’s triangle?
direct hernia
What arteries branch off the internal thoracic artery?
- superior epigastric a
- musculophrenic a
What arteries branch off the aorta?
- intercostal (posterior)
- subcostal aa
What branches off the external iliac a?
- femoral a
- inferior epigastric a
What branches off the femoral a?
superficial epigastric a
What supplies the superior abdominal wall?
internal thoracic a
What supplies the middle abdominal wall?
aorta
What supplies the inferior abdominal wall?
external iliac a
If something gets blocked in the venous system, what can provide flow into the axillary vein?
thoraco-epigastric vein
What are the superficial veins of the abdominal wall?
- axillary v
- thoraco-epigastric v
- superficial epigastric v
- femoral v
What provides a potential collateral pathway for blood normally draining via the IVC to return to the heart via the SVC when the IVC is blocked?
a venous anastomosis between the superficial epigastric vein and the thoraco-epigastric vein
What do the superficial lymphatic vessels of the abdominal wall accompany?
the subcutaneous veins
Superficial lymphatic vessels superior to the umbilicus drain mainly into what?
axillary lymph nodes
What are the different lymphatics of the abdominal wall?
- transumbilical plan
- scrotum
- testis
What does the inguinal ligament run from?
from ASIS to pubic tubercle
What is the relationship between the inguinal canal and the gonads?
indirect hernias
What is a passage in the lower anterior abdominal wall located just above the inguinal ligament?
inguinal canal
What functions as a passageway for structures between the intra and extra-abdominal structures?
inguinal canal
What transmits the spermatic cord, gonadal vessels, and lymphatics in males?
inguinal canal
Usually indirect hernias are _________ related
gestationally
What is 2MALTS related to?
boundaries of the inguinal canal
What are the boundaries of the inguinal canal?
- superior/roof
** internal abdominal oblique
** transversus abdominis - anterior
** external abdominal oblique aponeurosis
** internal abdominal oblique aponeurosis - inferior/floor
** inguinal ligament
** lacunar ligament - posterior
** transversalis fascia
** conjoint tendon
What overlies the superficial inguinal ring in the anterior wall of the abdomen?
conjoint tendon
What is the inferior border of the inguinal ligament?
- femoral a., v., n.
- lymphs
What is the superior border of the inguinal ligament?
- spermatic cord/round ligament of uterus
What are the layers of the spermatic cord?
- internal spermatic fascia (transversalis fascia)
- internal oblique and transversus abdominis (arcades)
- cremasteric m. and fascia (IO)
- external spermatic fascia (EO)
What has no contribution to the spermatic cord?
transversus abdominis muscle
What percent of all hernias are inguinal hernias?
75%
Of the inguinal hernias, how many are direct and how many are indirect?
25% are direct
50% are indirect
Direct hernias are due to what?
a defect in the abdominal wall (acquired)
Indirect hernias are usually what?
congenital
Inguinal hernias are rarely found where?
in the scrotum
Both direct and indirect hernias are more common in who?
males
What are predisposing factors of direct hernias?
- weak abdominal wall
- over 40 year old males
What is the frequency of direct hernias?
less common
What are the coverings at exit from abdominal cavities of the direct hernias?
peritoneum and F. transversalis
What is the course of direct hernias?
travels medial 1/3 of inguinal canal
Where do direct hernias exit from the anterior abdominal wall?
- superficial ring
- lateral to spermatic cord
- rarely enters scrotum
What is related to persistent processus vaginalis?
indirect hernias
What are the predisposing factors for indirect hernias?
- patent processus vaginalis
- younger male
What is the frequency of indirect hernias?
more common
What are the coverings at exit form the abdominal cavity for indirect hernias?
peritoneum + 3-fascial coverings of SC
What is the course of indirect hernias?
traverse entire inguinal canal
Where do indirect hernias exit from the anterior abdominal wall?
- superficial ring
- within spermatic cord
- commonly into scrotum/labia majus
What type of hernias happen in the upper abdomen at the midline?
epigastric
What type of hernias occur at the site of previous surgical incision?
incisional
What type of hernias occur at the navel?
umbilical
What type of hernias occur in the femoral canal?
femoral
What type of hernias occur near the opening of the inguinal canal?
direct inguinal
What type of hernias occur at the opening of the inguinal canal?
indirect inguinal
What are the subdivisions of the GIT?
- foregut
- midgut
- hindgut
What does the foregut give rise to?
- pharynx
- esophagus
- stomach
- cranial 1/3 of duodenum
- liver
- pancreas
- gallbladder
What develops independently in the GIT?
spleen
What is the blood supply of the foregut?
celiac artery (celiac trunk)
What does the midgut extend from?
1/3 the way along duodenum to about 2/3 the way across transverse colon
What does the midgut give rise to?
- caudal 2/3 of duodenum
- jejunum
- ileum
- cecum
- appendix
- ascending colon
- cranial 2/3 of transverse colon
What is the blood supply to the midgut?
superior mesenteric artery
What does the hindgut extend from?
2/3 the way across transverse colon to cloacal membrane (partition separating the endo derived cranial 1/2 of anal canal from ecto derived 1/2 of anal canal)
What does the hindgut give rise to?
- 1/3 transverse colon
- descending colon
- sigmoid colon
- rectum
- cranial 1/2 of anal canal
What is the blood supply to the hindgut?
inferior mesenteric artery
What lines the internal surface of the abdominopelvic wall?
parietal peritoneum
What invests viscera (organs) such as the spleen and stomach?
visceral peritoneum
What is the double layer of parietal peritoneum?
mesentery
What is the double layer of parietal peritoneum between organs?
omentum
