Alright guys, so now we're going to take a look at the coccyx bone or the hip
bone. And before I do that I want to kind of give you the three different
divisions of the coxa bone. So if we look here, we have the tape to kind of mark out the
three different parts of it. So if you ever see the tape, it's separating these
two bones right here. This one right here is the pubis, this one right here is the
ischium and then all this top one up here is the ilium. We're going to take a
closer look at each individual one starting with the ilium. One of the first
things I want to do is, I want to try to show you guys the orientation of the ilium.
So if you imagine, I'm trying to hold this like a gun and this my finger
that's the trigger finger or the trigger finger side is that's the anterior side
and anything over here is the posterior side, okay.
So now let's go ahead and take a look at this bone and each individual portion
right. So we look here, you have this little spine right there, a little bump
right there, that's called the anterior inferior iliac spine. Then if I come up
here, we have another spine that's called the anterior superior iliac spine. Then
I'm going to kind of move this all the way over here,
this is the iliac crest. Then I'm going to scrape this surface right here, this
is the iliac fossa, if I follow this all the way down it's kind of like a it
can't really see it very well, but there's a line right here and this is
actually called the arcuate line, actually which helps to form the pelvic
brim. Then if we come back here turn a little bit here, this right here is the
auricular surface of the ilium. Now the auricular surface of the ilium is
important because it articulates with the auricular surface of the sacrum to
form the sacroiliac joint. And if you look here, there's this little spine,
there this is the posterior superior iliac spine and this one is the
posterior inferior iliac spine. Then if you pretend going down a roller coaster
right here, this is the greater sciatic notch. This is the ischial spine. So now
we're heading into the ischium now. So now we're in ischium guys, so if we turn
over here, this is the lesser sciatic notch. Then we have the ischial
tuberosity right there, that roughened surface. And then right here is
the ramus of the ischium, there's a big hole right here, this is actually the
obturator foramen, the biggest holes in the body. And if I come over
here, now we're in pubis guys. So this is the inferior ramus of the pubis, this
part here, this is the superior ramus of the pubis. And again, this is going to be
the part of this articulating surface of the pubis, it's actually going to help to
form the pubic symphysis joint, which has again those nice fiber cartilage packing
between it. And I'm going to kind of turn this up this way guys.
So this right here, this little bump is called the pubic tubercle.
That's the pubic tubercle, right there. Then if I kind of move this part right
here, that is going to be called the pubic crest. So pubic tubercle and then
pubic crest okay. Now I'm going to kind of flip it on the
outside, here so we can see one more important thing and again, this is called
the acetabulum of the coxa bone. This is where the head of the femur articulates
with it, alright, to form the synovial ball-and-socket joint. All right. We'll
come back up here, to the ilium. This is actually going to be the posterior side
of it our gluteal muscles, they sit right here on this part of the bone okay. And
so they call this the gluteal surface. Now you can't see it very well, probably
not at all, but skeletal muscles are striated, so
they form these lines too. And those are called gluteal lines. And that's pretty much
covers everything you know about the coccyx bone.
All right guys, so now we're going to take a look at the whole pelvis. So if we
look here, we have the two coxa bones here articulating with the sacrum. And if
you know, that's going to help us again this is the sacroiliac joint right there.
And then this part right here in the front, this is the pubic symphysis and
that's actually going to be an amphathrotic joint. So cartilaginous joint made
up of fiber cartilage and again, this is going to be called a, specifically is called
the symphysis joint, the pubic symphysis. Alright, so if I take a look here and I
actually move and make a circle all the way around right here, this is actually
called the pelvic brim. And if you imagine putting a plate on top of that
anything above the plate or above the pelvic brim is actually referred to as
false pelvis and anything below the pelvic brim is true pelvis. Next
thing I'm gonna do is, I'm going to kind of pull this here back, so we can take a
look here. So if you look here, looks like an arch right? This is called the pubic
arch, the pubic arch is good for us being able to tell whether this is female or
male pelvis. As my professor said in the past, if it's broad it's a broad. So this
is a female pelvis, it's a very very broad pubic arch. Okay, one more thing is,
if you look here, this is the pelvic Inlet and this is the pelvic outlet. Or
you can think about it as, pelvic inlet anything in part here, pelvic outlet is
anything past this point right there. Alright guys, that gives us everything
we're going to need to know about the pelvis.