Now this one's kind of a fun one. It's the cauda equina or
you could say equina whichever way you want to say it.
Or we call it the horse's tail. Now start at the top with
me. The pons and medulla.
No seriously, I want you to literally take your finger and
follow down with me.
Engage your brain, cuz I don't wanna lose you in this part.
So sometimes it's hard to keep focused when we're going
through so much cool information.
But you've got the pons and medulla, then you've got the
foramen magnum, that hole in your skull.
Now you can see as we keep moving down, you've got like
spinal cord and the pia mater.
We've got like right at level T1 and C2, you see where those
Now we've laid the dura out there for you, T12, conus
medullaris, the filum terminale, and then the cauda equina.
It literally means a horse's tail. And if you look at it
there that's what it resembles, the horse's tail.
So, why is the spinal cord shorter than the vertebral
column? Hey, that's a pretty interesting question.
First of all, did you realize that?
Did you know that your vertebral column, the bone, is longer
than your actual spinal cord? It is.
It ends at the lower of either the first lumbar or the top
of the second lumbar vertebra.
So why would you do that? Well, it does protect your spinal
cord, but let me tell you how it happens.
During normal growth and development, a human being's
vertebral column outgrows the spinal cord.
That way we can keep it protected.
So, we don't find the spinal cord starting from the lower
lumbar region where the lumbar puncture is done.
Why is that beneficial? Well, we do lumbar punctures where
we do because the spinal cord isn't there so we don't risk
Okay. So we're gonna look even more at the spinal cord.
You see we've got it labeled for you there and it's situated
inside the vertebral canal, right?
So it's protected by those spinal meninges; that tough bone.
It's usually about 42 to 45 cm or 16 to 18 inches.
And it's about 2 cm or just a little bit over three quarters
of an inch around.
Now it starts from the medulla oblongata or a friend in the
brainstem and it ends at the --
well, just like we talked about, at the top or the bottom of
the first lumbar or the top of the second lumbar.
Okay. So we're helping you see kinda what do we know about
the spinal cord? How big is it?
How long is it? Where does it start and where does it end?
So again, make sure you pause the video, take a look at this
and see without looking at your notes.
Can you remember how long, how big, where it starts and
where it ends?
Alright, you're doing great. You already know so much about
the spinal cord that's gonna help you as a nurse.
Now let's talk about how you protect the spinal cord because
it's the information highway.
If anything damages it, we're gonna have big problems
controlling our bodies.
So first of all, you've got that bone and meninges, right?
Those are the -- the bone is what you're used to seeing, and
then the meninges are those tight protective layers.
Now remember I've got meninges in my brain, right? The pia
mater, arachnoid and dura.
Those are those tough layers that protect my brain. If I get
meningitis that's an inflammation of the meninges.
So first of all, I've got bone; that's tough structure that
will protect that spinal cord.
Then I've got the meninges, same kind of thing that I have
in my brain, I have around the spinal cord.
And I've got a cushion of fat. Now, this is the kind of fat
you want to have because it helps cushion that spinal cord.
I've got fat and a network of veins in the epidural space.
Remember the epidural space, same kind of area as when we
talked about the epidural space
in your brain between the vertebra in the spinal dura mater.
Okay. So, epidural is referring to the dura mater.
The dura mater, we've got that vertebra break in between
because what's cushioning that?
The fat and the network of veins. And that epidural space is
helping to protect the spinal cord.
Now we've also got cerebrospinal fluid in the subarachnoid
Let's take the words and translate them to the drawing,
So you see there that -- we have the bones. Do you see how
that's pointed up?
Looks like a 'W' on top of an upside down 'V'. Now take a
look where we have the pia mater.
We don't have the arachnoid mater labeled here for you.
But remember when we talked about padding your brain?
If we were looking in your head, it would be, P-A-D. Pia
mater, arachnoid mater, dura mater.
Now remember, they're not that Y. That was just being --
using hyperbole to let you see what the order that they go
But we've got the pia mater there, so we see where the
vertebral bodies are that's the bones.
Then we've got the pia mater. There you see the spinal cord.
And you see the white mater and the gray mater that you're
already familiar with.
And then you see that little coating of fat that we have in
the epidural space. Cool.
Now you see the dura mater and the subarachnoid space, we
actually labeled for you there also.
Just remember, we don't show you the arachnoid space in this
Okay. So, let's go back over to the words. Got bone and
meninges, see those there.
That's like the pia mater, dura mater. We've got a cushion
of fat and a network of veins.
And you see where that is in the drawing.
And lastly, we have the cerebrospinal fluid in the