hello and welcome to this exam question video we're carrying on from a previous video on
synovial joints if you haven't seen that one just yet then perhaps go and find that video on
the channel or inside the portal wherever you are watching this video where we labeled this
image up here it's the knee joint what we did was break it down on the white board and we labeled
all the different structures that are found inside of a synovial joint from the cartilage
to the capsule to the membrane to the ligaments to the sinus fluid to the cartilage and to the
bursas so what that question was talking about was labeling the soluble joint so that's what you need
to be able to do is just label the structures but this follow-up question then asks you
to not only identify the structure but also to describe its function what role does it play
in helping the performer helping to prevent injury helping the smooth running of a joint
and in this question they're asking you to pick one of the structures which is labeled above
so a or b which is our cartilage or synovial fluid but this could be more absent of the
diagram and you might just have to pick one of the structures or a couple of the structures and then
describe their function so if we just take the two in this diagram to start with which
with cartilage and synovial fluid so to stop the cartilage the function of that well it's to reduce
friction is to prevent the bones from rubbing against one another because if they were to do
that that would cause a lot of pain and possible breakages in the bone as well as it would build up
with friction and heat so that joint would start to creak and crunch and it wouldn't be able to
move through its range of movement as easily as it could do with healthy cartilage in place
they're also there to absorb shock so they're laid over the ends of the bones where they might
compress and contact each other and if that was a happen then the impact would be felt in
the bone but because the cartilage is there the cartilage can absorb it almost like a bit of a
buffer a shield it absorbs that impact and then dissipates it out towards the sides protecting
the bone underneath so we've got the friction and we've got the shock absorber absorption
benefits if you were to talk about synovial fluid well the main function of solution fluid is to
lubricate the joint it's to to lubricate all of the structures inside that solenoid synovial joint
so when they do articulate and when they do start to move around each other they're greased up and
they're lined with this slippery almost gel-like oil-like substance known as synovial fluid
as a result when surfaces do start to pass over each other we don't see friction beginning to be
created causing heat causing this joint to slow down causing more force to be required to move
that joint so synovial fluid is good to prevent the friction from building up and it can also help
replenish and almost provide nutrients to the structures inside that joint as well so within
the synovial fluid there are going to be nutrients that are supportive to cartilage regeneration
cartilage overall health so what replenishes the synovial fluid well if we had to label the joint
capsule which was this lighter gray zone around the exteriors of the joint well the silo sorry
the joint capsule is there for the the structure and supports the joint the lining that joint
capsule is the synovial membrane so if we were to write down the structure of the cylindrical
membrane what function does that serve but it's there to replenish and secrete synovial fluid
so that it stays healthy it stays fluid it stays liquid it stays responsive to temperature changes
so that it can continue its role of lubricating the whole joint the joint capsule is there to
support that joint structure to help prevent with absorption of impacts from external or external
sources for example a lateral hit to the knee or a lateral hit to the elbow it's there to absorb
that impact dissipate it around the edges of the joint and then sort of get rid of it towards the
side it doesn't let it sort of penetrate through the joints where damage could be caused and that's
that so for your exam questions make sure you not only know the structures of the synovial joint
you don't know you need to know where they are on a joint but you also need to know the functions of
them as well so i hope that helped and i'll see you again in the next video bye for now