Forearm Muscles PDF

All right, we are going to tackle the muscles of the forearm now There are a lot but there are a lot of helpful patterns and we'll cover in this Alright, so in terms of the organization of the forearm Just like in the arm will have flexors on the anterior side and extensors on the posterior side her...

All right, we are going to tackle the muscles of the forearm now There are a lot but there are a lot of helpful patterns and we'll cover in this Alright, so in terms of the organization of the forearm Just like in the arm will have flexors on the anterior side and extensors on the posterior side here In addition on our radial side, so it's going to be our thumb side Those muscles are going to abduct while the ulnar side is going to adduct, right? So if you kind of move your hand side to side, you can imagine abducting and adducting Alright in terms of our layers, we'll have generally three to four layers here The more superficial muscles are going to move the things that are closest to you, right more proximal So we are going to have the superficial layers move the wrist by crossing the carpals The intermediate layer is going to move the digits. Sometimes there's two layers here whether it's Digits two through five, which is our point here through our pinky or individual digits Finally our deepest layer is going to Pronate and supinate our arm or forearm. Pronate and supinate our arm or forearm. Excuse me Alright, so if we look at this, we have this muscle called the flexor carpioneres If we think about that in terms of the name flexor tells us it's on the anterior side Carpi means it crosses the carpals and ulnarus tells us it's on the medial aspect So our flexor carpioneres is this muscle here, right? So our flexor carpioneres is this muscle here, right? So flexor side Attaches past the carpals and on our pinky side, which is where our ulna is So we kind of think about the name of that flex your wrists on the ulnar side is what it means All right, so it tells you what it does Because this is basically like a foreign language though These would be good things to have as flashcards, right? To help you kind of learn that language All right So if we have a muscle that we're gonna ask for the flexes your finger fingers with the superficial muscle It's because there's two layers that flex our fingers What muscle do you think it what's the name of it, right? So flexor is going to be in the name for this one. So flexor And then our digits our fingers so digitorms is not either of these two So flexor digitorum and with that superficial layer of muscle superficialis, right? So we're looking at the flexor digitorum superficialis muscle Alright again, there's a lot going on here But we are on the flexor side because we're looking at the anterior view here Some nice landmarks that can help you find that is the flexor retinaculum here You know kind of the bulb of our thumb the base of our thumb a big muscle there and then the bicepil Aponeurosis also tells you your anterior. Aponeurosis also tells you your anterior. So a lot of these are gonna have flexor in the name So if we start on the lateral most side here, we're gonna have this muscle called the brachioradialis It's the only one of these superficial muscles here that's gonna come from that lateral aspect All others are going to come from the medial epicon dial of the humer So we can see that here and cross down to move our wrist or our digits So again medial epicon dial is an important attachment site So 1 2 3 4 muscles in this superficial area here The first one does not follow the pattern, but we will see it in the deepest compartment here This is going to be the pronator teres. It's going to attach to Really the radius at mid shaft here, right? So pronator teres is the first one the next muscle to come off that media up the condyle is a flexor Carpe radial is we come see it coming down. It's going to attach Past the carpels here, right? Past the carpels here, right? So it's gonna move the carpels and it's gonna be on the thumb side So flexor carpe radialis this next muscle is a pole mares longest And it's also gonna help you flex your wrist and it's a muscle that a good portion of the population actually doesn't have And then this last one here to come off that media epicondyle We can see coming down the lateral *** our medial aspect is going to be the flexor Carpe here. It is passing over the carpools and then all nearest because it's on the medial or pinky side here, right? So if we look at these muscles flexor is a common in their name and they're going to move the wrist here Which is more proximal of these structures? All right, if we look at the next layer down, we're gonna have the first of two muscles That's going to move the digits. We're gonna have digitorum in here this muscle flexor on the flexor side Digitorum superficialis we've already covered. Digitorum superficialis we've already covered. It's the more superficial the two in addition This muscle is going to have kind of this split in it that allows for the deeper Tendon to go through we'll see this next So flexor to do term superficialis when we look at it in this view we can see a characteristic Connected to opening here a tunnel here that we're gonna have the median nerve traveling through We'll see the median nerve in our next lectures That can help you kind of identify that here, right? So flexor digitorum Superficialis is going to flex digits 2 through 5 Our thumb is our number one digit here and it's going to flex it at our PIP joint and our MP joint because it attaches to our intermediate phalange The next layer down here then is going to be our flexor digitorum Profundus, right? Profundus, right? It's a profound. It's really deep and it's going to flex our digits, right? So the deeper of those two muscles flexor digitorum profundus, we follow these tendons the whole way down They are going to attach to that distal most phalanx That means they're gonna they're going to flex the dip joint the PIP joint Oh PIP joint and the MP joint because it's gonna cross all of those, right? If we look at it in this view here We can see that really the characteristic to identify is is it's got a lot of these Tendons coming off of it that are easy to identify. It's also deep to a lot of these structures We have a median nerve and have our own our nerve and our radial nerve here, right? From this view we can also see The flexor pollicis longus muscle. We're going to see that in We're gonna see that if we follow that that down It is going to attach to the flexor side of our distal most phalanx So flexing the thumb and it's long right flexor pollicis longus So it still flexes a digit but just one Alright, now we're in our deepest compartment here Here's that pronator teres that we saw a little bit earlier And you can see how it's going to attach to the radius when it contracts is going to help us Pronate or turn our wrist to pour the soup out, right? Here is our supinate. It's actually a really cool muscle here It's gonna attach from the ona Right here on the lateral aspect of it and then wrap around to the anterior aspect of the radius That is going to help us supinate or turn our wrist the other way or form the other way And then finally we have our pronator quadratus It is going to help the pronator teres in its action and it's got four sides and a square muscle for our quad muscle Alright now we are looking at the other side the extensor side that posterior side things that can tell us that we're looking at the Posterior side. I really like to look for the antonias right here. It's a pretty Clear muscle to find and tell you looking at the backside of the arm So if we look at the backside of the arm, we're looking at extensors, right? Another muscle that can help us to find what we're looking at and identify others is the brachioradialis We can at least see where it articulates or connects to the arm for brachio and it's on the radial side, right brachioradialis And so when we look at these muscles then that come off of it, we are going to have extensor Carpe radialis muscles. There's actually two portions to it and One's short and one's long. So we're gonna extensor carpe radialis Longus and extensor carpe radialis brevis All right, and those are gonna again come on down cross the carples on the thumb side right there, right? The other thing I want you to make note of is that these extensor muscles not brachioradialis really But the extensor muscles here are going to be associated with that lateral epicondyle, right? There's our projecting medial epicondyle. Here's our lateral epicondyle here The next muscle if we follow down it's got a lot of tendons associated with it So it is the extensor digitor no longest on that one longest is going to be in the leg All right, one more over gonna have this muscle that just moves our pinky finger We follow it down. You can see there's one tendon really we can keep following that tendon and it's going to go And help us extend our pinky. Whoops. So that's going to be the extensor digiti minimi or minimi Finally our muscle right here is going to be our extensor Carpe ulnaris because we're on the medial pinky side extensor carpe ulnaris So going through those again, we have two muscles that are extensor carpe radialis muscles Longus and brevis our extensor digitor muscle here with all the tendons Extensor digiti minimi going to our pinky and our extensor carpe Ulnaris muscle here. Okay All right. If we go one more layer down, we're gonna see a bunch of muscles that help move individual fingers Specifically our thumb for polisis and our index finger or pointer finger here So just looking at the order of them and where they connect it we're gonna have the first one here This is gonna be our abductor Polisis longus is going to help us pull our thumb up our thumb side up So abductor polisis longus this next muscle we can see is going down to the thumb and we are going to attach halfway up So this is going to be our extensor Polisis brevis is abbreviated short compared to our extensor Polisis longus here, right? So extensors are in the name here and it's gonna move our thumb one short ones long and then this last one Here's the one that's going to help us extend our digit our index finger, which is the pointer finger, right? So our extensor indices is that one right here looking at those within context here Here's our abductor polisis longus extensor polisis brevis our Extensor polisis longus and extensor indices our abductor polisis and our extensor polisis brevis actually do this really neat thing Where they wrap around? our extensor Radialis extensor carburetialis muscles right here All right. We are almost there. We are our muscles of the hand here At some point you will know these in more detail our thanar muscles are going to be those that act on our thumb Hypothenar are those that are going to really be on our pinky side These are where we'll find these brevis muscles and our our opponent's muscles and we're not going to do that in this year here So in addition to our thanar and hypothenar muscles, we're gonna have these long Lumbricles here. So our long kind of worm like lumbricles. You can see that they're going to come up and attach on the radial side of The fingers here the base of the fingers right there and there, right? They are going to do this a really cool thing because they're associated with this extensor expansion, right? So here's our lumbricle in green notice that When it crosses the MP joint, it's going to be on the anterior aspect But now it caught when it crosses the PIP and DIP joints, right? They're gonna be on the posterior aspect so we're gonna have a flexion of the MP joint and Extension of the PIP and DIP joints. So that's pretty cool kind of organization here Finally we will have our abductors and adductors of digits 2 through 5 rates of spreading out our fingers or bringing them in Our palmar and terosseae we're going to associate with the term pad Palmar is going to adduct AD our fingers and bring them closer to the midline and that's going to happen as we have these on our Second fourth and fifth digits and those muscles are going to attach towards the midline on midline side, right? Bringing our fingers in towards our middle finger. Bringing our fingers in towards our middle finger. Notice that our digit 3 does not have any This is in comparison then to our dorsal interosseae Interosseae between the bones, right? Interosseae between the bones, right? They are going to attach on both sides and they are going to help us spread our fingers out And that's gonna have to do with how they attach to our phalanges here. So dorsal interosseae I want to think dab for dorsal abduction versus pad adduction Our clinical correlation. So we said that our Extensor muscles are going to be associated with that lateral epicon dial Here's our thumb lateral side while our flexor muscles are going to be associated with our medial epicon dial, right? So here's our pinky side. So here's our pinky side. So that's medial. So in athletes who use their upper limbs a lot so you can think of Pictures you can think of tennis players golfers and so and so forth that repetitive action on the elbow can cause inflammation and Depending on what you're doing with your elbow and your your forearm That's going to affect either the flexor or extensor sides a little bit more or our medial and lateral Epicon dials and the tissue surrounding those right? So those individuals that Use their extensor muscles More often so just tennis players, right? More often so just tennis players, right? You're gonna pull back that racket in your hand That can cause and be associated with inflammation on our lateral epicondyle here called tennis elbow Versus individuals who use their flexors more often think of a golfer. For example we're gonna have an association with inflammation on our medial aspect with our Flexors here or flexors here. So our extensors associated with the Lateral epicondyle and our flexors are going to be associated with that medial epicondyle, right? So that can cause inflammation and pain and even constriction of the nerves that are associated with these Which we're going to learn in the near future Alright, that's the end of recording three