good morning anatomy colleagues this is dr alsup and welcome to station number 20 where we are
getting into the muscles of the lower limb so we're going to start with anterior compartments
specifically we're going to start with the anterior thigh and then we're actually going
to see some of the medial thigh as well so we're looking at a kind of anterior slightly lateral
view here you can see a bit of the gluteus maximus because i think it's rotated just a little bit
lateral and we're going to start with the sartorius muscle which i'm going to outline
real quickly here and you kind of lose it after a moment from this view because it is heading quite
medially so it starts laterally it's starting at this anterior superior iliac spine kind of that
end of the iliac crest region and then it's going to extend all the way to the medial surface of the
tibia so this is a very long muscle in fact it is the longest muscle of the body and i really want
you to note here that it is quite superficial it is kind of running over the quadriceps region so
it's in its even though it's considered part of the anterior compartment it is superficial to the
quadriceps portion over here just because we can see it is a muscle you're not having to identify
but it is quite visible here so i do want to point it out which is the tensor fasciae lattae muscle
and it's this really short uh belly it starts in the anterior superior iliac spine as well and it
will insert into the it band which is this very very thick component of the deep fascia that you
see on the lateral side of the thigh region so similar the gluteus maximus will also have most
of its fibers inserting on the iliotibial tract as well so that helps me when i can see the it band
i know that this has to be lateral and this is going to be more medial i t band is always lateral
okay focusing in on the quadriceps region this is a superficial dissection so we can only see three
out of the four muscles right running right down the middle will be the rectus femoris
muscle the one that is going to be the straight muscle and then on either side you'll have the
vastus lateralis and medialis so this is the lateral side so this will be the vastus
lateralis and this is medial making this the vastus medialis and you can really see how these
muscle bellies end and then you get into that very thick quadriceps tendon the patella would be right
in this region and from there on you would have the patellar ligament okay looking at a slightly
deeper dissection so same there's that it band again so this is lateral and this is medial this
is actually been cut at the pubic pubic symphysis so we know pubic synthesis is medial and one of
the dominant things that you can see in this image is this the large neurovasculature that is going
to run deep in this region which is the femoral neurovasculature and i hope that you recall
that the femoral nerve which you can see a bit of right here is really what is providing the
motor innervation to the anterior compartment and so that you can see it actually traversing this
region along with the large femoral artery and the femoral vein would also be here
okay so let's try to identify the iliopsoas and if you recall from our lecture videos that the
iliopsoas you can see the muscle belly a lot easier from looking around the vertebral
region or the pelvic region when they are the psoas major and the iliacus muscles and they
and this is so as major right here the iliacus is a bit of it right here so they will combine to
form the common tendon so right around this region you're getting into the iliopsoas it's quite small
in terms of being able to to see its insertion whereas it's not a small muscle at all it's just
when we get into the thigh region it looks kind of small but certainly not insignificant
you can see that the sartorius has been cut in this image in order to get a better view
of this whole region and then if we move back to the quadriceps region
as well the rectus femoris has been cut that's what has been removed right here
and so again you can still see the vastus lateralis and the vastus medialis but you can
also see the vastus intermedius because the rectus femoris has been removed and so you would have to
reflect or remove the rectus femoris in order to have a nice view of the vastus intermedius
and then lastly let's look at what we can see in a a slightly superficial dissection of the medial
compartment of the thigh or those adductors so again this is more that anterior compartment you
can see the rectus femoris right here sartorius has been cut you can see a bit of the iliopsoas a
little bit closer up this is vastus medialis and so over here kind of being divided here are the
quadriceps there's that femoral neurovasculature that's the vein artery and nerve over here
kind of from here on we are in that medial compartment or the adductor compartment
and the the most medial muscle in the adductor compartment is going to be the gracilis and it is
a very kind of strap-like muscle that will extend from the um it will extend from the pelvic region
all the way down towards the tibia so whatever is the most medial muscle in the thigh think gracilis
and then when you're looking at a superficial dissection really the only adductor muscle that
you can see well is going to be the adductor longus and that is this large muscle right here
the adductor long longus is large it's fan shaped it will include the view of the adductor brevis
as well as the adductor magnus which you can actually see better from a posterior view but
sometimes those hamstrings will kind of cover it so we don't have adductor magnus on here
and it's not that it's not a large muscle it's a very very large muscle but the majority of
what we're looking at for our lab purposes are more superficial dissection so it's actually
occluded by a lot of muscles but it's still a considerably large muscle and a very powerful
adductor as well all right excellent so that is the anterior and the medial
thigh muscles we will continue and to the next station where we will continue our discussion
of thigh muscles but we will be looking at a posterior view all right thank you for your
time and attention here and as always please feel free to reach out with any questions