ANATOMY OF KIDNEY AND URETERS Flashcards
what is the situation/ location of kidneys?
retro peritoneally
posterior abdominal wall
side of the vertebral column
what is the extension of kidneys in relation to vertebrae?
T11
to
L3
what is the difference between left and right kidney?
right kidney is slightly lower than the left cuz of the liver
So
Right kidney —-> T12- L3
left kidney —–> T11-L3
what is the location where you palpate the kidneys?
lower pole of right kidney —> right lumbar region
during deep inspiration in a lean person ( during inspiration the right kidney sink down by 1 vertebral levels )
left kidney is not palpable cuz many viscera overlies it
what is the level of the hilum of kidney?
transpyloric plane
L1
what maintains the kidney normal position ?
Intra abdominal pressure
renal fat and fascia ( Renal vessels, and fat within the fascia )
whats the clinical application of fats and fascia supporting the kidney?
if a significant weight loss over a short period of time
The fatty layers within the renal fascia dissolves resulting in sinking of kindeys
leading to NEPHROPTOSIS
when does the kidney move?
full respiration
change from supine to erect position
MOVES ABOUT AN INCH ( 1 VERTEBRAL BODY )
what are the anterior surface marking of kidneys?
Hilum ( transpyloric plane )—> 5 cm from the midline —> L1
Upper pole —–> 2.5 from the midline —> T12
Lower pole ——> 7.5 from the midline —-> L3
what are the posterior surface marking of the kidneys?
its called morrisons parallelogram
2 points marked at the level of T11 , 2.5 and 9 cm away from midline
2 points at the lvl of L3 same distance as above
Joint the points at quadrilateral space
Upper pole of left kidney —> 2.5 cm at T11
Upper pole of RIGHT KIDNEY —> 2.5 cm at T12
Surgeons prefer going posteriorly cuz less visceral anteriorly
Upper pole is more medial
lower pole is lateral
what are axis of kidney?
Long
Transverse
describe the long axis of kidney?
Directed downward
laterally parallel to the lateral border of psoas major
The poles of the kidneys are not in the same plane cuz upper pole is medially and lower pole is laterally
describe transverse axis of kidney?
BACKWARDS AND LATERALLY
we can see the lower pole directed laterally and backwards —> to accommodate the vertebral body ( bulges out )
what muscle we see parallel to the long axis ?
psoas major
what are factors keeping kidney in position ?
Pressure from neighboring viscera
disposition of renal fascia + renal fat distribution
pedicles of kidney attached to the hilum
what is the renal angle/ costovertebral angle?
angle between the lower margin of 12 th rib and lateral margin of erector spinae
THE kidney lies close to the body surface
The perinephric abscess causes swelling and tenderness at the renal angle
Renal pain is usually felt at the renal angel as dull ache
what are the coverings of the kidneys from within to outwards?
Fibrous true capsule
perinephric fat
Renal fascia/gerota
paranephric fat
describe the fibrous true capsule ?
Condensation of fibrous stroma of kidneys
covers entire organs —> line the wall of renal sinus
Whenever connective tissue of any organs form a cover around it , it will always be considered a true capsule —> when cut and peeled of –> u will see the cortical part of the kidneys ( parenchyma )
what is nephropexy?
Surgery to fix the movable kidneys , the fibrous capsule is divided along the lateral border of kidneys and posterior flap is rolled up and sutured to the last rib , muscle of posterior abdominal wall, etc
describe perinephric fat?
Between fibrous capsule and renal fascia
Extend into renal sinus
what is the renal sinus?
Space between the vessels and ureter on the medial aspect of the kidneys forming a small pocket of fat
it is considered the same as renal renal hilum
what is the definition of renal hilum?
depression on the medial border of the kidneys through which pass the segmental renal vessels and renal nerves and where the apex of the renal pelvis occurs
aka porta renis
describe the renal fascia / gerota?
Condensation of extra peritoneal connective tissue around the kidneys
continuous LATERALLY WITH FASCIA TRANSVERSALIS
The perirenal fat is inside the fascia
It is considered FALSE CAPSULE formed by extra peritoneal connective tissue
2 layers :
Anterior —> fascia of TOLDT
Posterior —> ZUCKERKENDLE
what happens to the renal fascia laterally ?
Both layers fuse
continuous with the fascia transversalis
what happens to the renal fascia medially?
anterior layer covers front of the kidney and RENAL VESSELS ( adventitia )
merges with opposite sides
what happens to the renal fascia superiorly ?
both layers fuse at the upper end
Encloses the suprarenal gland
attaches to the diaphragm
In cases of nephrotosis even though the kidneys go down, the suprarenal glands do not and stay cuz attached to the diaphragm
what happens to the inferiorly to the renal fascia?
2 layers DO NOT FUSE
Extends along the ureters and finally lost in the extra peritoneal tissue of iliac fossa
NOT ATTACHED ANYWHERE
whats the fat seen behind fascia of zuckerkend ( posterior layer of the renal fascia )?
paranephric fat
compare the paranephric fat to the perinephric fat?
perinephric fat —> between the true capsule and renal fascia
covers the entire kidneys
Paranephric fat —> in front of the renal fascia and thoraco lumbar fascia
ONLY in the posterior aspects
what is nephroptosis ?
abnormally mobile kidneys- –> may descend more than the normal 1 inch
suprarenal glands remain in place because they lie in a separate fascial compartment are are firmly attached to the diaphragm
Its distinguished from an ectopic kidney / congenital misplaced kidney by URETER OF NORMAL LENGTH :
In cases of congenital anomaly –> ureter is already short so the kidney is in its natural ectopic position
in cases of sudden weight loss and kidney falling down, the ureter would be really long
symptoms of intermittent pain in the renal region , results from traction on the renal vessels , relived by lying down ( pain cuz of kinking and binding of vessels )
The role played by the perinephric and paranephric fat in holding the kidneys in position explains the development of nephroptosis ( FLOATING OR DROPPED KIDNEYS )
After severe weight loss
describe renal transplantation ?
kidneys can be removed from the donor without damaging suprarenal gland
transplanted kidney is situated in the iliac fossa for support ( we are not removing the old recipients kidneys due to its anatomical relations —> the new donor kidneys will be on iliac fossa )
renal vessels are joined to the external iliac vein and internal iliac artery to be supported by pelvis
Ureter is sutured into urinary bladder
why does perinephric abscess extends to the pelvis?
Gravitational pull
no attachments to any structures in the pelvic region ( THE RENAL FASCIA INFERIORLY IS NOT ATTACHED TO ANYTHING )
compared to holdens line —> in holdens line we dont have a blind end
what are the parts of the kidneys?
2 surfaces —> anterior/posterior
2 ends —> upper 2.5 cm and lower 7.5 cm
2 borders —> medial and lateral
what is the posterior relation of LEFT KIDNEYS?
11th and 12th ribs and muscles
what is the posterior relation of RIGHT kidneys?
12th rib and muscles
Since its lower only 12
what are the muscles related POSTERIORLY
to both kidneys?
Lateral most —> Transversus abdominis
Superiorly —-> diaphragm
Medially —> psoas major, quadratus lamborum ( lateral to p. major )
NO iliacus muscle because it enters the pelvis and attaches to iliac fossa
so from medial to lateral :
P major –> quadratus lamborum —> transversus abdominis
what crosses the quadratus lamborum?
subcostal nerve and vessels
iliohypogastric
ilio inguinal nerves
what we do need to make sure of before liver and kidney surgery?
since the liver and kidney are close to the diaphragm
we need to make sure to not puncture the pleural cavity and puncture the lungs
what is the clinical significance of psoas major ?
since psaos major is parallel to the long axis of the kidney and it is among one of the posterior relations
inflammation of the surrounding pararenal areas like appendictis will causes characteristic severe psoas pain
which is aggrevated by the extending the thigh and relived upon flexion ( function of psaos muscle )
what are the anterior relations of the LEFT kidney?
Suprarenal gland lies on the upper MEDIAL aspects
SPLEEN lies on the upper LATERAL aspects
the stomach lies between the splenic and suprarenal areas ( BETWEEN MEDIAL AND LATERAL )
the tail of pancreas and splenic vessels cross the hilus and body ( TAIL PANCREAS AT THE HILUM )
the lower pole is in contact with coils of JEJUNUM MEDIALLY
The lower pole is in contact with the LEFT COLIC FLEXURE LATERALLY
what are the anterior relations of right kidney?
Upper pole medially —? suprarenal gland
hilum and medial border—> DUODENUM ( DESCENDING PART, 2ND PART )
lower pole —-> right colic flexure ( up ) and Coils of jejunum ( below )
the remaining of the anterior surface is by the liver ( superolateral )
what are the basic structural microscopic features of the kidney?
Outer cortex
inner medulla
describe inner medulla?
8-18 renal pyramids —> pale conical masses
what is a lobe of kindey?
1 pyramid capped with adjoining cortex
what is course from calyces to pelvis?
Minor calyces —> major calyces —> renal pelvis
what is the renal pelvis?
flattened funnel shaped expansion of the superior end of the ureter
Receives 2-3 major calyces
each major calyx divides into 2-3 minor calyces
each minor calyx is indented by renal papilla
what is renal papilla?
Finger like projections that have holes through urine flows out
apex of the renal pyramid which urine is excreted
what are the structures at the hilum?
from anterior to posterior :
Renal vein ( most anterior )
Renal artery ( middle )
Pelvis of the ureter (most posterior )
VAP
what is renal sinus?
narrow space within the kidney that is entered through the renal hilum
contains the renal pelvis , calices, vessels , nerves and fat
outermost space between the renal parenchyma and pelvis containing the renal neurovasculature
Describe the ureter?
narrow muscular tube ( 25 cm long ) – long retroperitoneal throughout their course
pelvis of the ureter —> Dilated upper end
upper part lies on the posterior abdominal wall
remaining part ( lower ) is within the pelvic cavity
what are the normal strictures of the ureter ?
Pelvi-uretric junction —> lower pole of kindey
Plevic brim/sacroiliac joint /bifurcation of common iliac artery
point of entry into bladder wall/intramural part —> narrowest of all , MEDIAL TO TIP OF ISCHIAL SPINE
these are potential sites of obstructions of ureteric stones
used for identifying sites of renal stones
what is the lymphatic drainage of kidney and ureter?
Kidneys + proximal part of ureter —-> lumbar set of lymph nodes
Distal part of ureters —> iliac lymph nodes
cuz it extends into the pelvic cavity
what is the blood supply of the ureter?
NO specific artery , small branches from nearby arteries
Branches supplying the abdominal half of the ureter approach MEDIALLY
pelvic half —> ARTERIES APPROACH LATERALLY
Proximal ureter via : renal gonadal and common iliac arteries ( along the medial aspects so during surgery ITS PULLED MEDIALLY ALONG THE BLOOD SUPPLY DIRECTION)
Distal ureter : INTERNAL ILIAC ARTERY AND ITS BRANCHES —-> SINCE ITS PELVIC PART THE BRANCHES COME LATERALLY —-> DURING SURGERY THE PELVIC PART IS PULLED LATERALLY ALONG THEA ARTERY
what is the sympathetic innervation of the kidney?
Derived from renal plexuses , preganglionic fibers - cord segments —> T11- T12
lesser + least splanchnic nerves —> Synapses in celiac or superior mesenteric ganglia —> renal plexus
Lesser splanchnic —-> carry sympathetics from T10-T11 level of spinal cord to the pervertebral plexus ( SUPERIOR MESENTERIC , CELIAC + AORTICORENAL )
Least splanchnic :
Carry sympathetics from T12 level of spinal cord to the prevertebral plexus ( RENAL PLEXUS + INFERIOR MESENTERIC )
what is the innervation of ureter?
Ureteric colic arising from calculus
wheres the referred pain of the ureter found ?
Cutaneous segments sharing spinal cord levels T11-L2
pain typically passes from the loin to the groin from lumbar region to inguinal regions as stones progress through the urters
Where could the pain extend?
thigh and scrotum or labia majora
genitofemoral nerves ( L1, L2 )
what is the origin of renal artery?
Abdominal aorta
at the lvl of intervertebral disc between L1 AND L2 at right angles of abdominal aorta
compare left and right renal artery?
the right renal artery is longer ( cuz the aorta is on the left side so right must travel longer )
pass behind the IVC
what do the renal artery divide to?
divde at the hilum into :
anterior and posterior branches
give rise to 5 segmental arteries
compare left and right renal veins?
Left renal vein longer ( Cuz IVC is on the right side )
left gonadal veins drain into it instead of ivc
what type of arteries are segmental arteries?
end arteries
they supply only specific areas without anastomoses
describe the renal arteries supplying the kidneys?
The area supplied by each independent surgically resectable until ( RENAL SEGMENT )
The posterior segmental ARTERY IS THE CONTINUATION OF THE POSTERIOR BRANCH OF RENAL ARTERY
the rest of the segmental arteries are BRANCHES OF THE ANTERIOR BRANCH OF RENAL ARTERY
so :
Anterior branch of renal artery is larger it give raise to 4 segmental arteries ( 2 apicals, 1 anterosuperior, 1 anteroinferior )
Posterior give 1 and its smaller ( 1 posterior and its continuation )
what is brodels bloodless line and what is the significance of it?
Since the anterior and posterior segmental arteries DO NOT ANASTOMOSIS AS THEY ARE END ARTERIES
they form a bloodless region without anastomosis ( avascular line ) , ITS OBLIQUE LINE
Can be used to access the kidneys without disturbing blood supply
describe abnormal renal artery ?
about 25% of kidneys receive directly from aorta 2nd , 3rd , 4th branches
enter either through the renal sinus or at the lower or upper poles
Persistence of a fetal vessels
not usually accompanied by veins
