So if we look at the individual parts of
the large intestine, then here we
have seen these diagrams before.
We are looking at the cecum and the appendix.
And here again we can see we have got the Ileum
we can see the appendix here
radiating away from the cecum.
And this is a posterior view, as if you are
looking at the cecum and the appendix through my
posterior abdominal wall, so we can
see the Ileum is radiating away
to the left in this direction.
And what we can see is radiating from
the appendix are these three
bands of longitudinal muscles.
There we have the mesocolic tenia,
which attaches to the mesocolon
or mesocolon attaches to this
taenia colic. We also have the
omental taenia coli where the greater
omentum is coming from this one.
And then we have the free taenia which I
mentioned previously doesn't have anything attached to it.
So we have these three bands of
longitudinal muscle. And if this was a
piece of small intestine, then obviously
we would have that complete layer.
Here we can we have got
the cecum and appendix again.
But this time the cecum
and the initial portion of the
ascending colon has been opened up.
So now we can see the opening of the
Ileum into the large intestine.
We can see the cecum here. We have got
nice look of opening for the appendix
which is the slender blind ended-pouch.
And then we have got the cecum
which is that little bag, little sac.
And then we have got the ascending colon
which will pass up in this direction.
The appendix is anchored via
the mesoappendix, is quite a small
piece of mesentery the mesoappendix.
And the position of the appendix as
we can see in this diagram here
is incredibly variable. So we can
see the, even though we open up the right
inguinal region and we should be
able to locate the appendix.
It may actually need some rooting around
to find it. Because the tail of the appendix
is the kind of tip can project into
numerous different directions. Here we see aligned
posterior to the Ileum. We see it
aligned anterior to the Ileum here.
Here we can see a poking on the straight
down as the continuation of ascending colon
And here we can see actually tucked
underneath the cecum. So although it's there
it may need some rooting out.
So if we just stick to the appendix
for little bit longer, then
the function of the appendix is not really
that well understood in the human.
In the lower animals, it's important in
being able to digest grass and various other
aspects of digestion. But in the
human it's really a lymphoid tissue
it helps to produce white blood cells
and a part of the lymphatic system
Now because it's a narrow blind
ended pouch, it can actually become
blocked. And If it
becomes blocked by faeces
and then it can actually can
swell and become inflamed. And that
creates appendicitis if it was to
become inflamed and potentially become
infected. Now we mentioned this when we
looked at the surface anatomy but now we understand
the anatomy of the appendix a bit more.
We may be able to appreciate
the position of the appendix in
this right inguinal region
and again we can locate
the umbilicus, we can locate
the anterior superior iliac spine.
And then align
down between these two points.
And then align
a third of the way from the anterior
superior iliac spine to the
umbilicus. So about here it's going
to be what's known as the McBurney's point.
And that is the position of
the appendix. So it can be very painful
appendicitis. And the pain initially
being felt in the midline where we just
have this dull ache. But with
time, the pain can progress to this lower right
quadrant in association
with the McBurney's point.