hello anatomy colleagues this is dr alsup and welcome to station number 15 where we are
talking about the bones of the leg so the tibia and the fibula not the tibula and the phibia
sometimes i hear it said that way but let's make sure that we get that pronunciation correct
now looking at the same image that we kind of been returning to in terms of the lower limb
you can really clearly see the tibia here the tibia is going to be the
the largest of the bones of the legs it will be the weight-bearing bone it will also be the medial
bone and i can't really see the fibula can you there's not much of it there i can see
a little bit right here of the lateral malleus of the fibula but in terms of the shaft i'm not
seeing it all that well i think i might see a little bit of it right there i think that
we've kind of rotated this a little to the medial side so the fibula is not quite as visible here
but it would be kind of following along this region right here so the fibula will be lateral
whereas the tibia will be medial so looking at the individual tibia there are the proximal portion is
going to be part of the articulation of the knee joint and this distal portion will articulate with
the talus and the fibula and you will have that formation of the talocrural joint
in this proximal portion you're going to have these really flat areas which are the condyles
and i would really only ask you to identify the condyles in a full with a full tibia just because
i think it's so easy to tell um that this is the medial malleolus and that medial malleolus is always
medial right just like its name would say so this would be the medial condyle whereas this would be
the lateral condyle now i would not ask you to identify the two condyles in this specific image
but i did put it here just because i really wanted you to be able to see how shallow these condyles
are so you have those fairly large femoral condyles that are fitting in these very shallow
medial lateral tibial condyles so that's why you don't have that that really great fit between
the knee so it's relatively unstable this would actually be the lateral and the medial but again i
won't have you identify it um from this particular view now what back to this image over here this
is a straight anterior view and i know that because i can really see this tibial tuberosity
that's right in this region and this is going to be that distal attachment site for the quadriceps
tendon or that specific portion from the patella down to the tibial tuberosity is referred to as
the patellar ligament so that is always going to be anterior you can actually palpate your
own tibial tuberosity you'll clearly be able to palpate your patella and then if you move down
inferior or distal to that you should feel that tibial tuberosity that's projecting anteriorly
and then again in this distal portion here this medial projection is going to
be the medial malleolus and you will have a matching lateral malleolus on the fibula
so looking at that fibula that we couldn't see very well on that that first image you see that
it is a very long but very thin bone and it will have a kind of more robust proximal end
and distal end and the proximal end is going to be the head and the distal end will be the
lateral malleolus and so it is difficult i think to tell which way is up and which way is down
so when you're looking at the head it's a bit more triangular in shape a bit more
bulbous so this is going to be the head whereas the lateral malleolus is kind of more tapered
in terms of appearance so not kind of trying to to be more angular it's more tapered and this is
going to be a little bit longer too in terms of its projection so that will be the lateral malays
so just keep in mind that these two structures and being able to tell them apart is a
a pretty difficult thing many osteologists you'll see them kind of holding a fibula
and flipping it up and down trying to figure out which side is which but that articular
surface for the lateral malleolus will be facing towards the medial side which we can't really
see here this is a more posterior lateral view but that would be facing towards the
talus because it's going to be part of that telocurl joint or ankle joint okay so that
is the tibia and the fibula and the things that we want you to be able to identify here
we will continue um our discussion of the bones of the lower limb with the bones of the tarsal
bones as well as the feet so i will see you at the next station please reach out with any questions