In this lecture we are going to look
at the kidneys and the suprarenal glands.
So we will start off by looking at the position
of the kidneys and the superarenal glands and
how that position is measured on to
the surface of the abdomen.
We will then explore their gross anatomy
by looking at the position within the abdomen
and their relations to other organs. We will look
at the kidney segments and their specific blood supply.
We will then look at the internal structure
of the kidney and the suprarenal glands.
Look how the renal pelvis is formed
and that gives rise to the ureters
and we will look at few
constrictions that they have
along their course. We will then look at the
suprarenal gland vasculature because
that can be quite complex. So the kidneys
are paired retroperitoneal organs
located against the posterior abdominal wall.
And they are really important in removing excess
water, salts and waste products from the body.
They are important in that they maintain
the correct balance of nutrients
and chemicals. So maintaining homeostasis,
the internal environment.
The suprarenal glands also play an important
role and that's in supporting the blood pressure
and releasing adrenaline. We will
explore that through this lecture.
So let's have a look at the surface anatomy
of the kidneys and the suprarenal glands.
Well here, the best way to
view the kidneys is posteriorly.
As they are located against the posterior
abdominal wall either side of the
lumbar vertebrae really
extending from T12 and L3
extending down from about T12 to L3. And
we can see that its sitting against
ribs 11 and 12. So if someone
was to damage the ribs,
they could then puncture the kidneys. So we
can see where the two kidneys are positioned.
This anterior view with the all other organs in
place, it's practically impossible to see the kidneys.
But again if we look at the posterior
view we can see both of the kidneys
here again associated with ribs 11 and
12 and sitting against vertebrae 12
T12, L1, L2 and pass about 3.
The right kidney is somewhat lower than the left
because of the liver. The presence of the liver
just pushing the right kidney down at touch.
So some key facts about these organs.
The kidneys, as I have mentioned they're paired
retoperitoneal organ located between
the transverse processes of T12 and L3.
It's important in removing excess
water, salts and waste products.
And maintaining the correct
level of nutrients and chemicals
in the blood, maintaining
this acid-base balance
and maintaining blood pressure by regulating
the amount of water we have within our body.
They pass urine to the bladder via the ureters and
then within the bladder, it's stored prior to micturition.
Each of the kidney is surrounded by a
tough renal capsule and considerable
fat, perinephric and paranephric fat which we will
see. And each of the kidneys is divide into 5 segments,
with each of these segments supplied
by a segmental renal artery.
The suprarenal glands, which we will
explore towards the end of the lecture;
these are located on the superomedial
aspect of each kidney. So if we return
the superomedial aspect, we can see the suprarenal
glands are going to be located
around about here on both of those kidneys.
And these are intimately associated with the superior
holes of the kidney. They have two parts,
an outer cortex and an inner medulla.
And as we will see these
are highly vascular glands.
So this is an in situ cartoon of the
kidneys. We can remind ourselves
of what we looking at. We have got the
aorta running down the midline here.
To the right of the aorta we have got the inferior
vena cava. And we can see we have got some parts
of the quadratus lumborum muscle,
we have got psoas muscle here
We can also see psoas
muscle here we can see the
part of the diaphragm around here. We can see where
the oesophagus has been cut as it passes towards the
stomach. And we can see that the kidneys have
this substantial amount of fat surrounding them.
And the supromedial aspects of each
kidneys, we see we have the adrenal glands.
So that's a general overview. They
are located between about T12
and L3. So this will be T12 and this will
L3. That's their approximate position
sitting in what's known as the paravertebral gutter; just
some depressions either side of the vertebral column.
Posteriorly as I alluded to
in the previous slide, there is a series of
relations, there is some nerves, muscles
subcostal nerve, we can see
and these are passing down here subcostal,
ilionguinal, iliohypogastric, we can see those
posteriorly to the kidney. We can see it is sitting on
some muscles: the diaphragm, the quadratus lumborum.
It's also just sitting lateral to
psoas muscle which we can see here.
Suprarenal glands sit on
the superomedial border
and there is intensive arterial
supply from the aorta.
Substantial renal arteries pass across to
the kidneys and the suprarenal glands also
have considerable arterial input as we'll see.
Both of these organs, the suprarenal glands and
the kidneys, are supplied by considerable fats
and this helps to hold
the kidneys in position.
The parietal peritoneum anchors
them to the posterior body wall.
They don't have a mesentery to suspend them. So they're surrounded
by the fats which provide them warmth, provide some protection
and it anchors them to the
posterior abdominal wall.