hi everyone let's talk about the musculature of the anterior compartment of the thigh so what
you're seeing here is the proximal upper limb so we can see the anterior superior iliac spine
of the pelvis here the pubic symphysis would be approximately here we can see a slight contour
of the gluteal region there so just for our own sake of orientation this is the lateral
side and this is the medial side the head of the femur would meet the acetabulum at the hip
sort of in the plane of that arrow and then the the knee joint would be there so in order to to
get to what you're seeing a considerable amount of dissection had to have occurred the skin and
subcutaneous tissue is removed the superficial veins and lymphatics are are gone but probably
most importantly the fascia Lata or the the the the fascia that would have encased the
thigh muscle has been removed rather expertly and this allows us to see some of the the
musculature here so the the first muscle that I would draw your attention to is the Sartorius
the Sartorius has the distinction of being the longest muscle in the human body and it's named
the Sartorius because it is the tailor's muscle so it approximately attaches to the anterior
superior iliac spine or the as-is and distally and we can't see this here but coming from the
the median portion of the tibia there is the PES anserine PES anserine translated is foot of the
goose and what this is is a tripartite attachment for for several muscles the Sartorius being among
them and so the Sartorius when activated and it is innervated by the femoral nerve as are the the
other anterior thigh muscles the Sartorius muscle is going to be responsible for flexion abduction
and lateral rotation of the of the hip joint as well as flexion of the knee because it's going to
to cross the the knee joint down to the tibia there there's another muscle which which also
originates from the V as is there and that's the tensor fasciae latae the tensor fasciae latae is
this muscle which I am outlining here it's running from the as is down to the I T or the iliotibial
band which we can see here that IT band is a specialization of the fascia Lata and it's running
down to the anterior lateral or Gerdes typical of the tibia and when when this muscle is activated
it also is responsible for abduction and medial rotation of the hip much like the Sartorius and
it's also a weak extensors of the of the knee and its primary importance in terms of function is to
provide stability postural stability to the the lateral knee the the remaining muscle or muscle
group that we can see is the quadriceps femoris group let me don't line that here you can't see
all of it but the quadriceps quad meaning four headed muscle of the femur or thigh consists of
four muscles there is the rectus femoris which I'm outlining here for you know that rectus femoris
muscle also takes its proximal attachment up at the anterior superior iliac spine and
it comes down via its tendon to the patella or the kneecap and from there the patellar tendon
continues on down to the tibial tuberosity and so what we have is this shared tendon from all
of the muscles of the quadriceps femoris that contains the patella and then we have the
patellar tendon to continue from the patella down to the tibial tuberosity the rectus femoris all
by itself is responsible for extension of the of the knee joint so we also have other muscles
which we can see of quadriceps for more so we've discussed rectus femoris we have vastus vastus
means a large muscle medialis which is this muscle here so recall this is the medial side so the
vastus medialis is their vastus medialis takes its proximal attachment site on the intertrochanteric
crest in the linear aspera of the of the femur and its distal attachment to the patella and then the
patellar tendon down to the tibial tuberosity the vastus medialis just like rectus femoris
is responsible for extension of the knee and if that was the vastus medialis vastus lateralis
should be very easy for us to find we can see that it's nestled between rectus femoris here
and the IT band the vastus lateralis takes its proximal attachment from the greater trochanter
and Linea aspera of the femur and then yep you guessed it via that tendon for quadriceps down
to the patella and then the patellar tendon to the tibial tuberosity then finally we have the
vastus intermedius which is not visible in this view but if we shoot ahead to this next view you
can see here and there we have cutaway rectus femoris to review or I'm sorry reveal a muscle
deep to it and that muscle deep to it is the vastus intermedius muscle vastus intermedius
muscle takes its proximal attachment from the anterior lateral femur and through the
quadriceps tendon down encapsulate the patella and then the patellar tendon down to the tibial
tuberosity and the vastus intermedius along with the lateralis and the medialis and rectus femoris
are all extensors of the knee so the the the final muscle that I would like to draw your attention to
is the iliopsoas muscle the onliest psoas muscle is a combination of the iliacus muscle and the
psoas major muscle psoas major as you recall from previous sessions descends down from the
transverse processes of lumbar vertebrae you can see that here it's a very useful muscle
for understanding the spatial relationships of nerves of the lumbar plexus and it is going to
merge with fibers from the iliacus the iliacus muscle part of it secluded here but it's it's
taking its origin in the superior iliac fossa and it comes down I'll just sort of - this because you
can't see it there and it joins with so it's major to form that iliopsoas muscle and it's
going to then attach to the lesser trochanter of the femur and this iliopsoas muscle is going to
be the most powerful flexor of the hip joint so so really bringing that thigh into into
flexion like a high step or if your your kneeing something or if that is stabilized pulling the the
trunk up so - to perform a sit-up is something else that you can you can do with that muscle
isn't that wonderful so while we're here it probably would do us well to mention some of
the neurovascular that we can see here that is supplying this compartment so we can see
coming down here this is the femoral nerve see it branching out there the femoral nerve is the
innervation for this anterior compartment we can also see here the femoral artery
here's the femoral artery and it becomes the femoral artery from the external iliac artery
so that external iliac artery when it travels underneath the inguinal ligament becomes the
femoral artery there's also the femoral vein that femoral vein is contiguous with the
external iliac vein so that also at the inguinal ligament is is going to transform its name here
and those are some of the the important neurovascular elements that that serve
this muscle compartment so we've discussed the anterior thigh largely its muscles and
a little bit of its neurovascular so I thank you for your time take care