hello all this is dr alsup and in this video we will be focusing on the basics of the vertebral
column so we're going to start with talking about the different parts of the vertebral
column specifically the vertebrae and then we will get into the joints and ligaments of the column
and the vertebral column is called many different names sometimes you hear it referred to as the
spine which is sometimes used to refer to just the spinal cord which i'm not so into the spinal
column you may hear so numerous different names we're going to try to stick to the vertebral
column for our purposes and it's more than just bone because there's also going to be joints
formed by the articulations of the bones of these vertebrae as well as ligaments and this column is
going to surround the spinal cord and associated nervous tissue as well as importantly the meninges
and there are five types of vertebrae that help make up the vertebral
column these first three are going to be movable vertebrae and they're going to begin superiorly
and continue inferiorly and these last two types are going to be considered immovable
or fused vertebrae making up separate name bones so we're going to start with the movable
vertebrae beginning superiorly with the seven cervical vertebrae and we're going to get into
how to distinguish vertebrae from one another in another learning objective video but for now
let's understand that the cervical vertebrae are going to be superior they are associated with the
neck and they are named c1 through c7 c1 would be the most superior and moving inferiorly there
are 12 thoracic vertebrae and these will articulate with the ribs that we will see
as we move through the year and there are five very large lumbar vertebrae in the
lower back region and i like to remember the number of the different types of vertebrae
by the times that i eat so i eat breakfast at 7am i eat lunch at 12 and then i always catch
that early bird special and eat dinner at 5 p.m so that kind of helps me with remembering that
five sacral vertebrae will fuse or form bony joints to form the sacrum and there is no
movement between these vertebrae and the sacrum does articulate with the hip or the coxal bones
on either side forming the sacroiliac or s.i joints and these si joints are capable
of some movement and then most inferiorly you will have four kind of remnants of vertebrae
these and they will be fused coccygeal vertebrae typically therefore they will start kind of larger
and get very very small by the fourth one and quillocally we refer to this as the tail bone
okay moving on to joints and starting with the superior most the one that actually articulates
with the skull or the head so the joint between the occipital condyles and the superior articular
facets of c1 or the atlas think of atlas holding the world on his shoulders that is where the name
comes from and this joint will permit nodding the head yes so think slight flexion and extension
moving down one there is a joint between c1 and c2
and actually it's really composed of three different joints so you'll have two facet joints
which will kind of be on the opposite side of these superior articular facets of c1 so kind
of on the bottom portion because we're looking at a superior view here and then a more midline
pivot joint which is going to be between the dens as you can see here this little projection of c2
projecting up to around the c1 level here and this allows for a rotation or a pivoting motion
so if you think of shaking your head no this is occurring here at this joint
but speaking of facet joints there are a lot of them
throughout the movable vertebral column between neighboring inferior
and superior articular facets and you can see one right here there would be one right here two with
the neighboring one and one right here so pretty much the whole way down the vertebral column
and there will be slight gliding movements that are allowed here
lastly and some may argue most importantly are the intervertebral discs which are located
between neighboring bodies so this is the body of the vertebrae this is a body
it will be located between these neighboring bodies between c2 and c3
down all the way to between l5 and s1 so you'll have one between each one of those bodies
and these are actually not synovial joints but instead examples of symphyses which are a type
of cartilaginous joint so it is the cartilage that's really connecting these articular bones
and it's composed of two layers as you can see on this other side of the image an outer
annulus fibrosis which serves the function of connection and protection of the inner
nucleus pulposus which is semi-fluid in composition and will be responsible for
much of the flexibility of the iv discs and really that vertebral column as a whole and the nucleus
pulposus is actually a remnant of the notochord which is the embryonic mostly cartilaginous
rod-like structure that will develop into the vertebral column so this is a remnant of that
and it is this nucleus pulposus that may herniate through the annulus fibrosis
and we'll talk a little bit more about that in another video but if you think we've got spinal
cord right there we're gonna have nerves exiting this region so herniation can have implications
lastly let's finish our discussion of the vertebral column with some of the most important
ligaments as you can't talk joints without talking ligaments associated with the bodies of the
vertebrae there will be anterior and posterior longitudinal ligaments and you can see the
anterior longitudinal ligaments on the anterior side of the bodies as its name would suggest and
the posterior longitudinal ligaments would be on the posterior side of the bodies the all is going
to be um important in terms of limiting extension of the vertebral column so no hyperextension
or not allowing that the pll is going to be weaker and is clinically relevant as it helps
to prevent or redirect posterior herniation of the nucleus pulposus so if that fails as well
that has implications between the apices or these most posterior portions you will have
what's referred to as the supraspinous ligaments these are typically only present between c7 and l4
but are chord like and robust and will merge with the ligamentum nuchae or the nuchal ligament as
you can see here which extends from the external occipital protuberance and kind of bridges that
gap between the relatively deeper and shorter uh spinous processes of the cervical region
the interspinous processes are going to be um connecting the rest of the spinous
processes so kind of from that root of the region to the abysses
the ligamentum flava will serve to connect adjacent laminae
or those flat portions of the vertebral arches and you can see that really nicely right here
flavous means yellow and you can't see it in this image here because it's black and white but the
the ligamentum flavum is or flava's very distinct yellow shade to this ligament as it is composed of
yellow bands of elastic tissue and really helps to serve to resist separation of the laminae during
movements of the vertebral column and helps to preserve that normal normal curvatures of the
vertebral column you can also see a nice view excuse me of the interspinous ligaments here
between those spinous processes that have been cut
okay thank you for your attention here and as always we finish with
the summary slide for the this specific learning objective
please do reach out with any questions you may have and have a great rest of your day