inferior margin of the transversus abdominus
-most attaches to anterior 2/3 of iliac crest - lowermost fibres arise from the lateral 1/2 of the inguinal ligament --> arch upwards and into tho the pubic crest via the conjoin tendon with the internal oblique
inferior margin of the rectus abdominus
body and crest of the pubis
route and insertion of psoas major muscles
fibres converge and head beneath the inguinal ligaments --> converge with iliacus muscle as the iliopsoas tendon and insert into the lesser trochanter of the femur
layers from superficial to deep of the anterior abdominal wall
- skin - superficial fascia - rectus abdominus - external oblique - internal oblique - transversus abdominis - fascia transversalis - extraperitoneal fat - serous pariteal peritoneum - visceral peritoneus
where are the lumbar veins relative to psoas
lumbar veins sit behind psoas major
renal arteries split into the
segmental arteries
what is the pectineal ligament
the linear extension of the lacunar ligament that lies along the pectineal line
narrowing throughout the ureter
beginning (where the renal pelvis narrows to become the ureter) end (where the ureter enters the bladder) middle - compression/kinking produced as the ureter tips over the pelvic brim
lateral margin of the rectus abdominus
clear lateral border - linear semilunaris
surface marking of the gall bladder is where
where the linear semilunaris intersects with the costal margin on the R side
where is the internal inguinal ring
halfway between ASIS and pubic tubercle, a fingers breath above the inguinal ligament
where is visceral peritoneum
surrounds abdominal viscera
posterior margin of the transversus abdominus
attaches to thoraco-lumbar fascia
renal pelvis formed by
the uniting of 2 or 3 major calyces (each in turn receives 2 or 3 minor calyces (receives the apex of the downward pointing pyramidal components of the medulla))
next muscle lying lateral to psoas major/minor superiorly
quadratus lumborum
next muscle lying lateral to psoas major
psoas minor
next muscle lying lateral to psoas major/minor inferiorly
iliacus muscle
superior margin of the retus abdominus
overlaps the costal margin and attaches to the anterior surface of costal cartilages 5,6 and 7
origin of psoas major muscles
from the lower border of T12 to the upper border of L5 (attached to the bodies, the discs and the medial ends of the transverse processes)
orign, route and insertion of iliacus muscle
arises from the iliac fossa --> fibres converge and pass beneath the inguinal ligament, meet the psoas fibres, and together they insert via a conjoint tendon (iliopsoas tendon) --> insert into the lesser trochanter
position exactly of the psoas major muscles
lie in the gutter between the bodies and transverse processes of the lumbar vertebra
venous drainage of the anterior abdominal wall
dual system - anastomose - by IVC (canal system) - by portal venous system
function of quadratus lumborum
stabilises the 12th rib and laterally flexus the spine
difference between intraperitoneal viscera and retropertioneal viscera
intra - organ completely surrounded by visceral peritoneum and connected to the posterior abdominal wall by a mesentry retro - pareital peritoneum only goes over the front of the organ (the posterior part of the organ sits back on the posterior abdominal wall)
what is mesentry
the double fold of peritoneum that goes to surround the viscera
order of movement through the inguinal canal
- creates an opening in the transversalis fascia = deep/internal inguinal ring - traverses the inguinal canal - exits through the superficial/external inguinal ring
medial margin of the external oblique
meet with fibres from the other side at the linea alba (midline vertical raphe)
what forms the floor, roof, anterior walls and posterior walls of the inguinal canal
floor - inguinal ligament roof - arching fibres of internal oblique and transversus abdominus anterior wall: external oblique aponeurosis, internal oblique muscle (lateral) posterior wall: transversalis fascia, conjoint tend (medial)
where is the lumbar plexus relative to psoas
within psoas
origin of psoas minor
from the lower borders of T12 and L1
where is the neurovascular plane of the anterior abdominal wall
lies between internal oblique and transversus abdominus
inferior margin of the external oblique
inferior fibres insert onto the anterior half of the iliac crest and the pubic tubercle and pubic crest
what is important about where the 3 layers of the thoracolumbar fascia fuse
it is the anchor point for the muscles of the abdominal wall
posterior margin of the external oblique
free posterior edge
major structures of the kidney hilum from anterior to posterior
renal vein renal artery dilated upper part of the ureter (renal pelvis) (also nerves and lymphatics)
surrounding the kidney...
fibrous capsule perirenal fat renal fascia
where does the innervation of the anterior abdominal wall originate from
segmental innervation by the ventral rami of T6-L1
length and position of the ureter
25-30cm long - initially relates to psoas as it passes down the posterior abdominal wall --> then tip over the pelvic brim --> run around the lateral wall of the pelvis and into the bladder
direction of fibres of the transversus abdominus
horizontally forwards towards the midline
inferior margin of the internal oblique
- most fibres take origin form the anterior 2/3 of the iliac crest - lowermost fibres actually arise from the lateral 2/3 of the inguinal ligaments --> arch over and downwards and insert into the pubic crest with transversus abdominus via conjoined tendon
where do the gonads develop
in the extraperitoneal fat of the superior lumbar region of the posterior abdominal wall
lateral and medial parts of all three abdominal muscles
lateral - fleshy medial - aponeurotic
direction of rectus abdominus
long vertical muscle
origin and insertion of quadratus lumborum
arises from the posterior half of the iliac crest and the iliolumbar ligament and inserts into the inferior border of the 12th ribs
framework of the position of the poster abdominal muscles
fills in the gap left between 12th rib above, the posterior half of the iliac crest inferiorly and lateral to the lumbar vertebra 1-5, sitting in the paravertebral gutters
where are the levels of the tendonous intersections of the rectus abdominus
- umbilicus - xyphisternum - halfway between the other two
3 layers of the thoracolumbar fascia
- posterior leaf - attaches to the tip of the spinous processes - middle leaf - attaches to the tip of the transverse processes - anterior leaf - attaches to the anterior aspect of the transverse processes 3 layers fuse at the line of the tip of the 12th rib
where is the sympathetic trunk relative to psoas
lying on the front
foetal development of the kidney in respect to positioning in the body
starts off lower in the posterior abdominal wall due to differential growth rates --> kidney changes position --> T12-L3 (means they take change their blood supply throughout their development moving upwards through the abdominal wall)
position of the right kidney relative to the left kidney
right sits slightly loweer than the left due to the liver
function of tendonous intersections of the rectus abdominus
breaks up the vertical ascent of the fibres to make them more powerful (more powerful than one long muscle)
routes of right and left renal veins
right - straight across into the IVC left - crosses anterior to the aorta and then into the IVC
what makes up the mesentery
where the serous parietal peritoneum reflects off as a double fold of peritoneum to surround viscera
major roles of the abdominal muscles
- muscles of active expiration - increase abdominal pressure to assist with evacuation processes
size of kidneys
10cm long, 5cm wide, 2.5cm thick
landmark of T10
umbilicus
compartments of the thoracolumbar fascia
posterior compartment - contains erector spinae anterior compartment - contains quadratus lumborum
position of the kidney in the abdominal contents
lateral to lumbavertebral column and psoas, in the paravertebral gutters on quadratus lumborum, adjacent to T12-L3, intimately related to the diaphragm - retroperitoneal
first muscles lateral to the lumbar vertebra of the posterior abdominal wall
pair of psoas major muscles
superior margin of the transversus abdominus
underlaps the costal margin
Superior margin of the external oblique
overlaps the costal margin onto the anterior surface of the lower 8 ribs lying edge to edge with pectoralis major and serratus anterior
shape of right and left adrenal glands
right - pyramidal shaped which sits right on the top of the kidney left - crescent shaped - sits at the superior aspect of the medial border
macroscopic anatomy of the cortex and medulla of the kidney
- outer, pale continuous cortex - inner, discontinuous darker medulla arranged as a series -of pyramids
where is the superficial/external inguinal ring
it is the medial triangular opening in the external oblique aponeurosis between the attachments of the internal oblique and transversus abdominus
medial margin of internal oblique
linea alba (vertical raphe of the midline)
what forms the rectus sheath
the aponeuroses of the 3 lower muscles of the abdominal wall
insertion of psoas minor
blends in with the fascia overlying psoas major
what is the inguinal ligmanet
the thickened free inferior edge of the external oblique spanning from the ASIS to the pubic tubercle
blood supply of the anterior abdominal wall
- superior epigastric (branch of internal thoracic artery - inferior epigastric (branch of external iliac artery) - (superficial epigastric lying in the superficial fascia)
function of the inguinal canal
passageway that the testes takes through the anterior abdominal wall once its go down from its beginnings in the extra-peritoneal fat on the posterior abdominal wall
timescale of testes migration
12th week in pelvis 28th week - close to the beginning of inguinal canal 3 day traverse through inguinal canal in the scrotum a couple of weeks later
fascia of the posterior abdominal muscles
enclosed by the thoracolumbar fascia (except for psoas which has its own fascia = psoas fascia)
landmarks of the pelvis
iliac crest with ASIS pubic crest with pubic tubercle
direction of fibres of the external and internal obliques
external - front pockets internal - back pockets
placement of the right and left renal arteries (relative to the abdominal aorta)
come out horizontal from the abdominal aorta (left arises slightly higher than the right) - right goes behind the IVC - left straight into the renal hilum
posterior margin of the internal oblique
take origin from the thoro-columnar fascia
anterior and posterior surfaces of the rectus sheath
anterior - complete posterior - complete until about an inch below the umbilicus - disappears at the arcuate line
the hilum of the kidney faces which direction
anteriomedially
superior margin of the internal oblique
edge to edge to the costal margin
what is the lacunar ligament
where the inguinal ligmanet thickens medially and extends medially into a crescent shaped ligament extending onto the peritoneal lining of the pubic bone
