hello all this is dr alsup and welcome to station number 12. where now we're
into the posterior or extensor compartment of the forearm and we're not going to get
into as much detail in terms of identification for the posterior muscles of the forearm because the
deeper that we get into this compartment the more difficult it is to identify the muscles
so i'm going to have you focus on muscles i think that are a little bit is easier to identify and
then you can understand the bigger concepts more conceptually through the lecture videos so we're
only looking at the superficial compartment here this is going to be lateral and this
will be medial i know that because i can see the first digit or the thumb here so always lateral
and there are actually whereas there is only one flexor carpi radialis
there are two extensor carpi radia radialis there will be a longus which is this one right here
the extensor carpi uh radialis longus is going to be partially overlapped by this muscle here which
is actually the brachio brachioradialis which we saw a little bit clearer on the more anterior view
and the proximal attachment for the extensor carpi radialis longus is actually going to be above the
lateral epicondyle so just superior to the lateral epicondyle right next to the extensor carpi
radialis longus will be the brevis so the extensor carpi radialis brevis is just next to the longus
it does have its proximal attachment on the lateral epicondyle and kind of from
here on out these other muscles also have their proximal attachments on the lateral epicondyle
next to the brevis kind of in between the brevis and the flexor carpi ulnaris
is going to be the extensor digitorum and the extensor digitorum is very clearly within the
superficial compartment whereas we had the flexor digitorum superficialis being in the
intermediate compartment in the flexors and then the profundus and the deeper compartment but you
can clearly see that the extensor digitorum is very much within the superficial you can even
see kind of how it's starting to separate into different tendons here and so the i kind of think
of it as this middle muscle when we're looking at the posterior forearm so extensor digitorum
will have the long tendons that are extending to um to the digits on the extensor or posterior side
and then right next to it what i have labeled with the u will be the extensor carpi ulnaris
so this is kind of the medial most muscle in this posterior compartment you do have some
other muscles that you can see here you can see a little bit of the triceps brachii this is a
muscle called anconeus that we didn't get into too much detail but is visible from this view
and then you can even see some of those flexor muscles particularly the flexor carpi ulnaris
because you see we're on the ulnar side or the more medial side here so recall that in
the anterior view we couldn't see the flexor carpi ulnaris very well we can only
just see the tendon you can see a little bit better actually on the posterior view
all right so those are the posterior muscles of the forearm that you are going to have to
identify again realize that we did not go through the complete and exhaustive set of the muscles of
the forearm but we are focusing on the ones that i think you'll be able to identify more
and keep in mind if we discussed any specific muscles in the the lecture videos then those
are fair game for that type of assessment thanks for your time and attention here
again with forearm muscles they take a little bit longer i think in terms of
identifying and getting familiar with that so please feel free to reach out with any
questions you may have there thanks for your time and attention and i'll see you at the next station