hello welcome to this exam question video uh in this one we are going to be looking at synovial
joints in figure 2 in this question here we have the knee joint which we know because we
can see the patella which is the suspended bone uh just towards the the side of this diagram and
it's basically asking us to label the structures now before we get into labeling a and b for the
answers what we'll quickly do is run through what the sun oval joint is made up of so i
jump into the whiteboard and if we just crudely draw sort of the femur coming down and then our
tibia coming up from the base what we do have first off r if i change the color of that one
we have the ligament that attaches bone to bone so the first one there we have ligaments that attach
bone to bone now in order to keep everything on the of the joint enclosed in one place
what we do have is the joint capsule which runs around the exterior of the joint it's obviously
internal so it's below the muscles but where the bones actually meet it wraps around the exterior
and on the inside of that joint capsule we then have i put it in orange we have the synovial
membrane so this gel-like rubbery like substance lines the inside of the joint capsule not all
the way around but this is just a um sort of a an overall diagram of the synovial joint
inside of all of this is then where we have the synovial fluid which is there to help lubricate
and to help make sure that the space inside of the joint stays friction free and the the
ends of the bones can actually move across each other without friction without heat without pain
and then the last thing that we're going to add on here is our cartilage so i draw this in purple and
the cartilage wraps around the end surface of the bones which are meeting inside of the joint itself
so we've got the purple there is the cartilage we've got these blue wavy lines as the synovial
fluid we've got the synovial membrane in orange which is on the inside of the joint capsule
which is in green and we also have the ligament there which is suspended across the two bones
and then obviously external to the joint we would then have if i just put in this brown color here
is then where we would have the muscle attaching down into the tendon onto the ends of the bone
and vice versa on the other side tendon into the bone like that obviously around there we
do have the vascular network as well so plenty of veins and arteries and capillaries supplying this
whole region with its blood flow but that's the the basic structures of a solenoid joint
the only thing that you would add into that would be a bursa which is a sack-like clump
of synovial fluid the way in my mind i picture it is imagine if you have a lumpy jam you've got some
fluid like jam and then within that you also have some thicker clumps of the strawberry
or the raspberry the blackberry whatever it might be but it's essentially the same material
there's just more of it in a denser sort of more packed in clump in certain places and these are
in the hot spots of the joint so for example we might have a bursa down here where there's
particularly high amounts of friction and impact between the joint capsule and the end of the bone
and perhaps on the underside here where we might have a little bit of extra friction and impact
between the ligament and the end of the bone of the cartilage so bursas are also there and i've
just drawn those in pink so if we jump back to the exam question figure 2 shows the diagram of
the knee joint label a and b well now we've got that picture in our mind from the one that we've
just drawn a is pointing to the end of the bone the thing that wraps around the end of the bone
so we know that to be cartilage and then we have b pointing to the void the space this lined off
area which we now know to be synovial fluid but as you can see there is a ligament there we have got
the solid membrane in the slightly darker shade and then the joint capsule which is surrounding
the rest of this joint and then like we said the muscle on the top with its tendons with a
patella there as well and obviously the femur and the tibia that are up there meeting but
that is that so i hope you found it useful i'll see you again in the next video bye for now bye