AHE (3.2) Part 1 PDF

All right, so we are going to start with our Appendicular musculoskeletal system right that's going to refer to our upper and lower limb and include some Additional bones such as the clavicle and the scapula and so forth We're gonna start with joints though because they are an integral part of this...

All right, so we are going to start with our Appendicular musculoskeletal system right that's going to refer to our upper and lower limb and include some Additional bones such as the clavicle and the scapula and so forth We're gonna start with joints though because they are an integral part of this We can divide joints by the type of tissue that creates them and the type of movement So we have fibrous cartilaginous and synovial joints. We'll spend some time in the synovial joints because they are more complex Fibrous joints are going to have dense regular connective tissue and then cartilaginous joints are going to have hyaline or fibrocartilage Cenarthrosis means immobile Ambiarthrotic arthrosis means slightly mobile and diarthrosis is going to refer to those freely mobile Joints that we commonly see with the cenovial joint All right in terms of fibrous joints, we Will have three different types. They've already seen one type here, which is going to be the sutures in the skull They don't move hardly at all. So they're synothorotic Gomphosis are going to be a tooth joints, right? So we're our teeth are going to be held in place by joints We'll cover that more in our digestive system today. We are going to see though our syndesmosus joints here Right, and these are going to be dense regular connective tissue that spans between two bones And we will see that today in the forearm and in the leg And then if we move on to our cartilaginous joints, we covered one of these two types during our developmental lecture So synchroendrosis are going to be These joints that we see at the end of long bones Where we have actual growth occurring right that longitudinal growth Which will eventually be replaced by bone When we are adults and that's when we stop growing, right? And then today we will see an example or two of symphysis This is the type of joint it is slightly mobile. So anthropothorotic And it it's going to be comprised of fibrocartilage We'll see this today in the pubic synthesis as well as we saw last time in our intervertebral discs Now we'll see a lot of We'll see several synovial joints today. So we want to look at those more closely These are portions that all of them are going to have right? So everything all synovial joints will be comprised of an articular capsule or a joint capsule. That's going to be a tough Connective tissue capsule that covers where these two bones will meet Within that capsule we will have a joint cavity This importantly is going to be filled with synovial fluid That is going to help cushion but also provide nutrients for the related tissue You can see here in pink is the synovial membrane The synovial membrane is going to lie in the large portion of synovial joints within one in them And that is actually going to be the portion that creates the synovial fluid which is going to then again nourish these Avascular surfaces which is where that hyaline cartilage is going to be. We have both extrinsic and intrinsic ligaments Associated with synovial joints extrinsic means are going to be kind of separate and on the outside They'll help support and then intrinsic ligaments is going to be are going to be continuous with that joint capsule We can see the joint capsule here in this image The articular cartilage the hyaline cartilage is going to remain on the ends of these long bones within the joint cavity to increase Smooth motion right allows to have smooth motion and decrease friction We will often also find a number of other structures. We will often also find a number of other structures. So bursa are these fibrous sack like structures They're kind of can think about them as little fluid filled pillows And they are going to help cushion Joints Tendons are going to be those connections between muscle and bone These are going to aid in stabilization of these joints and then fat pads as well So we'll often have additional adipose tissue in here that provides additional protection Alright, so we're going to look at the bones of the muscular skeletal system And you can see here that we're going to separate the muscular skeletal system into really our shoulder, right? Arlenohumeral joint our arm which has one bone our forearm with two bones And then at the hand will have the wrist comprised of carpools the hand comprised of Our metatarsals metacarpals, excuse me, and then our fingers are comprised of phalanges on the images in these Recordings I have labeled them with the different directions that are going to be pretty integral for you to interpret what you're seeing So here we see our shoulder joint, right? We can also call this the shoulder girdle or the pectoral girdle. We will have a number of bones that comprise of the clavicle posteriorly here sitting on the back of the Thrasicage is going to be our clavicle. We see that on both sides and then we have our humerus, which is the arm bone Taking a look at the clavicle more individually. We will see that it has two different connections This one here is going to be our our sternoclavicular joint right here. It is actually a Synovial joint which have synovial fluid within here our sternoclavicular joint moves a lot more than we might imagine So if you shrug your shoulders and put your hands on your clavicles, you'll see that it moves up and down quite a bit And this is an important joint also because is the only point of direct Articulation between the upper limb the entire upper limb and our axis or axial skeleton You'll notice that even though the scapula is closed is not actually connecting to anything, right? So this is the only point where our upper limb directly connects to the rest of our body So this is going to be the sternal end of the clavicle if we go to the other side We're going to have the acromial end and that is going to help form the acromioclavicular joint The chromial end is named for this process here on the scapula which we will cover called the acromion We can also see another projection right here called the coracoid process We will cover this again more in the next when we go through the scapula These processes are important to identify because we are going to have basically our upper limb hanging off the clavicle We'll ligaments that help Stabilizer or that connect our upper limb from the core cord process to the clavicle. This is wrong This should be our acromioclavicular joint, right that we see right here from the acromion to our clavicle And then we have a core co acromial ligament And this is actually only on the scapula, but it's part of this region here. This is really going to help us Keep our our glenohumeral joint from dislocating or moving upwards here Alright, so a clinical context Hopefully you recall the sternocleidomastoid muscle right that has clido in the name for clavicle Our clavicle is actually one of the most commonly fractured or broken bones in the body Often it will break kind of at this at the in the middle ranks. This is kind of the thinnest portion of it When this happens, we kind of get this characteristic upward movement of the proximal clavicle, right and that is because although we can't see it in this radiograph The sternocleidomastoid muscle is pulling it upwards in this image We can also see that we have a dislocation of the core that clavicle acromioclavicular joint here as well Okay, in terms of our scapula what I want to bring your attention to is The directions right so if we look at these structures these projections processes They're all going to point or project laterally, right? That's going to help you side the bone. So our humerus is going to Articulate with our scapula at this glenohumeral cavity and everything's going to project that direction Look at the other side will have a long medial border here This long medial border is characteristic And then finally here we have something called our subscapular fossa a muscle the same name will sit there Importantly though this tells you that this is the anterior Portion of it because we want a smooth surface sitting on our thoracic or rib cage here, right? We'll compare this to the posterior view where we have this big structure kind of projecting off, right? So that tells us we're looking at the posterior view This is called the sparring of the scapula. We will have fossa above it super and below it infra and In those fossa we will have muscles sitting within that those are going to be part of the rotator cuff Group of muscles that we'll see here in a little bit We can see our acromion here and as well a little bit of our coracoid process All right looking now the proximal humerus That's going to help make up our glenohumeral joint here The head is here heads of all long bones or at least the the humerus and the femur are always going to point Immediately because that's where they connect with the body, right? We have both an anatomical neck here and a surgical neck and the anatomical neck Is defined because it's a constriction next to the head or adjacent to the head Whereas our surgical neck here is going to indicate more clinical Importance, right? Importance, right? So this could be for example where we have are more commonly to break our our humerus, right? The last two things that I want to well that one more thing three more things to point out are Our tuberosities up on the proximal aspect our greater tuberosity here is lateral our medial Turocity is more medial or a lesser. Turocity is medial in between there We do have a groove or sulcus where one of the heads of our biceps is going to actually come up and attach But these are going to muscle attachment points Notice that the greater tuberosity is also Found or you can view it as well on the the posterior view as well, right? So again muscle attached muscles are going to attach on this a greater tuberosity specifically many of those rotator cuff muscles Now the last thing down here. We will see If we have to side the humerus our medial epicondyle is going to be a nice characteristic to look for Our medial epicondyle is going to project Further I guess or more prominently when compared to the lateral epicondyle and we will see how this plays a role when we look at the elbow joint All right, so here's our glenohumeral joint with our Connective tissue on it, right? So here's the core plate process the acromion and the clavicle and then here we have our articular capsule We have this joint is very unstable because we can Move it in so many different directions, right? It's highly mobile but unstable And that means we have to have a lot of connective tissue and muscle actually to help Stabilize it so this entire structure here is going to be that joint capsule That has intrinsic ligaments on it. We have a superior middle and inferior intrinsic ligaments. Those are part of the joint capsule If we look here we can see inside This joint cavity we can see that as a synovial joint. It is going to have this joint cavity, which is where the synovial fluid will be located and we can also see that The joint membrane your particular membrane here And then one more important kind of clinical relevant aspect is going to be our corgo Humeral corgo humeral. There we go. Join. This is going to alongside the corgo chromial joint make sure that we Keep our joint in place specifically so we don't have a superior dislocation of this structure now because it's highly mobile and unstable that means that we are going to have dislocations happen in this and that is joint right on the most common type of Dislocation in the shoulder joint is going to be an anterior inferior Dislocation meaning that the head of the humerus is going to move inferiorly first and then anteriorly We can see a normal Radiograph over here versus a dislocated Humorous on this side. You can see that it's inferiorly located. Here's our glenoid cavity where we would have that head of the humerus fit So again, we have a series of bones and ligaments that help make sure our joint doesn't dislocate Superiorly here. Superiorly here. And so we have this inferior anterior dislocation that is fairly common in this joint Okay, the distal humerus, right? Okay, the distal humerus, right? Why did I point out that medial lateral epicondyle? It's because when we're looking at this we need to know which direction we are looking at or what aspect we're looking at So our medial epicondyle is going to project more Our lateral epicondyle is not as projected And then anteriorly we're going to have a small indentation. All right, this is the coronoid fossa Um in this if we look at the posterior view here, we're going to have the big oleicronon fossa. So those are things to look for Um to figure out which aspect you're looking at Uh, you see this most turtles can't laugh. This is to help you Identify these structures. So most is medial epicondyle Turtles is the trochlea. Turtles is the trochlea. We're going to have the ona articulate here Capitulum is can't and then lateral epicondyle is laughs The capitulum is going to articulate with the head of the radius and also make up our elbow All right, so here is our elbow joint, right? All right, so here is our elbow joint, right? Okay, so we can see this big broad articular capsule here That is um helping with the stability and so forth. It is also It's also the outside of our joint cavity here. We can see that synovial fluid or synovial membrane Surrounding this where we're going to get our fluid from This is here for your reference when we talk about the limbs or the bones of the forearm here So here's the radius and this is the ona We talk about this joint A lot because there are a lot of really important structures in this area We have very large artery and vein coming through here and three of our Pretty prominent and important nerves here. So here's our ulnar nerve. Here's our median nerve coming through here and here's our radial nerve All right. So let's look at this elbow a little bit more, right? This is an anterior view. This is our posterior view We can see that the ona is going to be associated with the trochlea These two bones allow us to have two actual types of joints here, right? So we have the hinge joint which allows us to flex and extend our forearm But we also have the head of the humerus that allows us to pivot, right? Um, this is going to allow us to supinate and pronate. Here's pronation and then supination is the other way, right? And our joint capsule is going to keep all of this together We also have this lovely kind of naming system, right? So our olecranon process of the ona is going to sit within the olecranon fossa of the humerus We're going to have our trochlear notch right here, which is going to hold the trochlea And we are also going to have the coronoid process this little projection on the ona Eventually and can meet up with I should say the coronoid fossa um Our radius is always going to be lateral Right in an anatomical position and our and our ona is always going to be medial though that association or Relationship is going to be really helpful When we learn the muscles here All right, trying to think if there's anything else I want to point out here All right. So clinical correlation correlation Um, if we look at the back of the of the elbow joint here Going over our lateral aspect. So it's actually going to be on this side We have two different sides of the bone two different limbs here But going on the lateral aspect of the distal Humorous, we're going to have our our ulnar nerve traveling. The ulnar nerve is going to travel posteriorly here and then shoot anteriorly Going through a structure called the cubital tunnel. The cubital tunnel is important because it's a restricted space, right? so it's can't really um when we have A damage to this area when we have osteophyletic growths with degenerative changes when we have swelling This ulnar nerve can be compressed which is going to affect all the muscles and skin that it innervates A distal to it, right? So, um, this is a common location of entrapment of a nerve that can be observed In our motor and sensory symptoms Okay, the last portion here we have um our wrist right in our hand so we have our distal radius and ulnar articulating with our carpels here Here are the carpels they make up the wrist then we're going to have our metacarpals here At the distal aspect of our metacarpals. We're going to have a metacarpophalangeal joint Um, the metacarpophalangeal joint is going to be Then associated with our proximal phalanges and then here our middle or intermediate phalanges and our distal phalanges so the the joint between our proximal and middle phalange is called the pip joint right the proximal interphalangeal joint and then we'll have our dip joint right here distal interphalangeal joint um knowing these and being able to recognize what they Are created by it's going to be important for learning our muscles because some are going to go and move the distal Some are going to move the proximal. Some muscles are going to move just that MP joint All right, looking at our carpels We have a kind of a cilling acronym if you want to look at your right hand At the kind of very base of your thumb really in your wrist here So not the base of your thumb really um where that big meaty part of your your thumb is Is where we're going to find these so some lovers try potions that they can't handle, right? So if we associate that with our bones here, we're going to have some scaphoid Lunate lovers try catch room. Try Um Some oh, here we go. Scaphoid some scaphoid lunate try catch room Um, the piece of form is here this little p like structure um, so That is going to be the trapezium. They is trapezoid can't is our Capitate and then handle is our hamate If we look at our our view here, um, the scaphoid is here, right? So we're going to kind of read this like we're going across some lovers try We'll try back their positions that they can't handle If we look at the palm of the hand and we think about um the clinical correlation correlation here um Our scaphoid and our hamate are going to be these bones that are going to take the brunt of a fall Right if you put your hand down catch yourself So our scaphoid and our hamate are uh, the most commonly fractured bones during the fall the hamate Especially because we have this little hook on the hamate All right, that's the end of first recording