Week 1 GI workbook part 1 Flashcards
what are the four different quadrants of the abdomen?
right upper quadrant
left upper quadrant
right lower quadrant
left lower quadrant
what is the horizontal line dividing the quadrants?
linea alba
name the 9 regions of the abdomen
right and left hypochondrium
epigastric
right and left lateral abdominal
umbilical
right and left inguinal
pubic
what are the two horizontal planes that divide the 9 regions
subcostal
transtubercular
what organs are found in the right hypocondriac region?
The liver
The gallbladder
The small intestine
The ascending colon
The transverse colon
The right kidney
what organs are found in epigastric region?
The esophagus
The stomach
The liver
The spleen
The pancreas
The right and left kidneys
The right and left ureters
The right and left suprarenal glands
The small intestine
The transverse colon
what organs are found in the left hypochondriac region?
The stomach
The top of the left lobe of the liver
The left kidney
The spleen
The tail of the pancreas
Parts of the small intestine
The transverse colon
The descending colon
what organs are found in the right abdominal region?
The tip of the liver
The gallbladder
The small intestine
The ascending colon
The right kidney
what are the organs found in the left abdominal region?
A portion of the small intestine
A part of the descending colon
The tip of the left kidney
what organs are found in the umbilical region?
The stomach
The pancreas
The small intestine
The transverse colon
The medial extremities of right and left kidneys
The right and left ureters
The cisterna chyli
what organs are found in the right inguinal region?
The small intestine
The appendix
The cecum
The ascending colon
The right ovary and right fallopian tube in females.
what organs are found in the left inguinal region?
Part of the small intestine
The descending colon
The sigmoid colon
The left ovary and the left fallopian tube in females.
what organs are found in the pubic region?
The small intestine
The sigmoid colon
The rectum
The urinary bladder
The right and left ureters
The uterus, the right and left ovaries and the fallopian tubes can be found in females
The ductus deferens, seminal vesicles and prostate in males
what is a dermatome?
Dermatomes are defined as the area of skin supplied by a single spinal nerve.
what dermatome is the umbilicus in?
T10
what is the vertebral level of the umbilicus?
Between L4 and L5
in relation to your pockets what direction to the external obliques run?
in the direction of you putting your hands in your jacket pocket
what is the orientation of external oblique muscle fibres?
inferomedially and interdigit with slips of the serratus anterior
what is the action of external obliques?
compress and support abdominal viscera flex and rotate trunk
what is the innervation of external obliques?
thoraco-abdominal and subcostal nerves (anterior rami of T7-T12 spinal nerves)
what is the orientation of internal oblique muscle fibres?
fibres fan out so upper fibres are perpendicular and its lower fibres are parrallel to those of external obliques
what is the action of internal obliques?
compress and support abdominal viscera flex and rotate trunk
what is the innervation of internal obliques?
thoracoabdominal nerves (anterior rami of T7-T11), subcostal and first lumbar nerve
what is the orientation of transversus abdominus muscle fibres?
fibres exept for the most inferior run horizontally
what is the action of transversus abdominus?
compress and supports abdominal viscera
what is the innervation of transversus abdominus?
thoracoabdominal nerves (anterior rami of T7-T11), subcostal and first lumbar nerve
what is the orientation of rectus abdominus muscle fibres?
mostly enclosed in rectus sheath, do not run legnth of muscle, they run between three or more tendinous intersections - each firmyl attached to anterior layer of rectus sheath
what is the action of rectus abdominus?
flexes trunk (lumbar vertebrae) and compresses abdominal viscera stabilizes and controls tilt of the pelvis (anti lordosis)
what is the innervation of rectus abdominus?
T7-T12 spinal nerves
The rectus sheath is formed from the aponeuroses of three muscles.
List them in order from superficial to deep
external obliques
internal oblique layer
transversus abdominus
what are the two muscles that lie within the rectus sheath?
rectus abdominus
pyramidalis
In the centre of the rectus sheath is a horizontal line of connective tissue known as?
linea alba
what is the function of pyramidalis?
Pyramidalis muscle tenses the linea alba. The muscle usually contracts together with the other abdominal muscles, contributing to contracting the abdominal wall and increasing the positive abdominal pressure
The line where the posterior layer of the rectus sheath ends is known as what?
arcuate line
list the order of abdominal muscles from superficial to deep to the abdominal cavity?
external obliques
internal obliques
rectus abdominis muscle
transversus abdominis muscle
transversalis fascia
extraperitoneal fat
parietal peritoneum
what is the superficial vasculature of the anterior abdominal wall?
superior epigastric vein
inferior epigastric vein
superior epigastric artery
inferior epigastric artery
where do the superior epigastric arteries arise from?
internal thoracic artery
where do the superior epigastric veins drain to?
internal thoracic vein
where do inferior epigastric arteries arise from?
external iliac artery
where do inferior epigastric veins drain to?
external iliac vein
what may happen to superficial veins secondary to portal hypertension?
they may become dialated in severe cases, leading to caput medusa (formation of dilated abdominal wall veins which extend from the umbilicus)
where does lymphatic drainage go to above the umbilicus?
axillary nodes
where does lymphatic drainage go to below the umbilicus?
superficial inguinal nodes
why does the inguinal canal form?
forms due to descent of the testis and its passage through the anterior abdominal wall to reach the scrotum
has to be pulled down to its level in the adults, in the female.
It remains in the pelvic cavity. But in the male, the testis has to pass through the layers of the anterior abdominal wall to enter into the scrotum.
And it is doing this because for Spermatogenesis, you need a temperature about a couple of degrees lower than in the abdominal cavity.
So as the testes passes through the anterior abdominal wall, it makes this canal called as the inguinal canal.
And as the testes moves down, it pulls its blood supply along with that.
where are both female and male gonads formed in the abdomen?
L1 L2 - level to the lower thoracic upper lumbar region is where the testes and the ovary first form.
what is the gubernaculum
A gelatinous tissue, the gubernaculum, pulls the testes through the abdomen, through the inguinal canal in the groin, and down into the scrotum. The pulling action occurs as the gubernaculum is stimulated first to grow and then to shrink
how long is the inguinal canal?
4cm
where does the inguinal ligament originate?
anterior superior iliac crest of the ilium
where does the inguinal ligament attach?
pubic tubercle of the pubic bone
The inguinal ligament is formed from the aponeurosis of which muscle?
The inguinal ligament is formed by the thickened, reinforced free inferior edge of the aponeurosis of the external oblique muscle as this attaches to the bones of the pelvis
The superficial inguinal ring is a break in the aponeurosis of what muscle layer?
The superficial ring is an opening in the external oblique aponeurosis, lying above and medial to the pubic tubercle.
What anatomical point is used surgically to determine the location of the superficial inguinal ring?
pubic tubercule
Where is the deep inguinal ring positioned in relation to the pubic tubercle?
The deep ring is a defect in the transversalis fascia. Found above the midpoint of the inguinal ligament (lateral to the epigastric vessels).
The deep inguinal ring is an oval shaped opening in which muscle layer’s fascia?
transversalis fascia
what are the four borders of the inguinal canal?
anterior, posterior, superior (roof) and inferior (floor) walls
what is the anterior wall of the inguinal canal?
aponeurosis of the external oblique, reinforced by the internal oblique muscle laterally.
what is the posterior wall of the inguinal canal?
transversalis fascia.
what is the roof of the inguinal canal?
transversalis fascia, internal oblique, and transversus abdominis.
what makes up the floor of the inguinal canal?
inguinal ligament (a ‘rolled up’ portion of the external oblique aponeurosis), thickened medially by the lacunar ligament.
During periods of increased intra-abdominal pressure, the abdominal viscera are pushed into the posterior wall of the inguinal canal. What occurs to prevent herniation of viscera into the canal?
the muscles of the anterior and posterior wall contract, and ‘clamp down’ on the canal.
what are the male contents of the inguinal canal
Spermatic cord – contains neurovascular and reproductive structures that supply and drain the testes
Ilioinguinal nerve – contributes towards the sensory innervation of the genitalia
Note: only travels through part of the inguinal canal, exiting via the superficial inguinal ring (it does not pass through the deep inguinal ring)
This is the nerve most at risk of damage during an inguinal hernia repair.
Genital branch of the genitofemoral nerve – supplies the cremaster muscle and anterior scrotal skin in males
what are the female contents of the inguinal canal
Round ligament (biological females only) – originates from the uterine horn and travels through the inguinal canal to attach at the labia majora.
Ilioinguinal nerve – contributes towards the sensory innervation of the genitalia
Note: only travels through part of the inguinal canal, exiting via the superficial inguinal ring (it does not pass through the deep inguinal ring)
This is the nerve most at risk of damage during an inguinal hernia repair.
Genital branch of the genitofemoral nerve – supplies the skin of the mons pubis and labia majora in females.
how do the walls of the inguinal canal ussually appear and why?
collapsed around their contents, preventing other structures from potentially entering the canal and becoming stuck.
what are the layers of the spermatic cord?
external spermatic fascia
cremaster muscle
cremasteric fascia
internal spermatic fascia