Skeletal System | Bones, Articulation, Growth & Development (FULL LECTURE)

0:00We're covering classifications or types

0:02of bones just based on their shape. And

0:05we did this with other types of tissue.

0:07Remember, there's four types of tissue

0:08in the body. Epithelial, connective,

0:11muscle, and nervous. And we look at

0:13connective tissue. There's three types.

0:15Connective tissue proper. We learn

0:18connective tissue fluid and now

0:19supporting. And supporting includes our

0:22cartilage and bone. So, we're on to bone

0:24now. But we start by just naming how do

0:26we describe them and compare them to

0:28others based on their shape or or type.

0:31We start to do this with epithelial

0:33tissue because we name based on cell

0:35layer and the shape of the cells.

0:37Remember we talked about cuboidal

0:38columnar. So we do the same thing with

0:41bones because we try to compare them and

0:44especially when we start to learn how

0:45they grow and how they develop through

0:48osteogenesis and bone development which

0:50is oification. So, our classification of

0:52types of bone, simply put, one is long

0:55relative to another one is short. So,

0:58we're comparing them relative to other

1:00bones. So, our our long bones include

1:02things like the femur, the humorris, the

1:05tibia, the fibula, relative to bones

1:09like the toarscils. And here are the

1:11carpals. So, there's eight carpals here

1:13that we'll come back to naming them in a

1:15future video, but these are short bones

1:18relative to the long one. So, you have

1:19short bones. And then we get into things

1:21like flat bones. So flat bones, I showed

1:24two examples here. First, the sternum is

1:27a flat bone. This bone takes about 20 25

1:30years for it to completely all fuse

1:31together. And then we have our ribs. We

1:34have different types of ribs. We have

1:36true and false and floating. And they

1:38curve, but relative to other bones,

1:41they're still flat. So they may curve,

1:43but relative to a long and a short,

1:46they're flatter bones. Okay? And then

1:49irregular. They're all over the place.

1:50Some of my facial bones. So my face is

1:53irregular. And my vertebrae. So this is

1:56stacking three vertebrae here. But they

1:58they're not long, they're not short,

2:00they're not flat. They're kind of all

2:01over the place. So we call them

2:02irregular.

2:04And then sesimoid bone. The primary

2:07example any text will give for a

2:08sesimoid bone is the patella. And

2:10sesimoid bone means sesame like it looks

2:14like a sesame seed. And this is looking

2:16at the kneecap or patella. And it's

2:18going to be surrounded by other types of

2:20tissue. So I'll have other connective

2:23tissues in our connective tissue proper

2:25that will cover over the top of this. So

2:27it's actually embedded in other types of

2:30tissue. This makes it a sesimoid bone.

2:32We see this also in our hands and our

2:35feet, but the primary example is going

2:37to be your patella. And then sutral

2:40bone. So I have dense fibrous tissue

2:43that helps connect all of my cranial

2:46bones. And when I look at facial, we'll

2:48come back to sutures as well, but

2:50they're sutral and it's the boundaries

2:52of each of these bones as they come

2:54together and fuse. And so later videos,

2:57we'll talk about fontels and how we see

2:59those early on in development. And then

3:01sutures and suture bones are just these

3:04tiny little fragments that help create

3:07the actual skull or cranium. And these

3:10connections we'll learn as we describe

3:12how the bone develops and comes

3:14together. So sutral bones. And then

3:16lastly, pneumatized bone. Some texts

3:19don't talk about pneumatized bone, but

3:22this is an example of the ethmoid bone.

3:24So the ethmoid bone comes right in top

3:26of my nose and it'll show up on the

3:28inside the cranial floor when I open up

3:30the cranium. But a pneumatized is

3:33essentially it's an irregular bone, but

3:36the difference is it has a lot of air

3:38sacks to it. And this helps with like

3:40our sinuses and draining when we think

3:43about just getting into our nasal

3:45cavity. But we also use it to breathe.

3:48So as air goes through the different

3:50holes that we'll describe with the

3:51ethmoid bone, it helps us stimulate the

3:53olfactory nerve, cranial nerve number

3:56one for olfaction or smell. So

3:58pneumatized by definition meaning it has

4:01more air sacks to it. We'll see in other

4:03types of bones the temporal bone has a

4:05landmark called the mastoid process that

4:08has air sacks to it. So it's unique in

4:10the sense and how it's developed. So I

4:13have long short flat irregular sesimoid

4:17sutral and pumatized. These are shapes

4:21and we describe them as classifications

4:23of bones or types of bones. And now

4:25later in next video we'll talk about the

4:28makeup of bone. How do we get to this

4:30point to where we see these types? We're

4:32covering the makeup of bone. How do we

4:34actually create a bone? Later we'll talk

4:37about growth and development. But we

4:39start out which what are the actual

4:41cells that give me the tissue that we

4:43see. Remember there's four types of

4:45tissue and we look at connective tissue.

4:47We said it's specialized cells that make

4:49a matrix. When we learned epithelial

4:52tissue, we describe one of their

4:53characteristics as cellularity with

4:56tightly bunched cells, not much material

4:58in between relative to the other

5:01tissues. When we cover connective tissue

5:04and look at bones, now we have cells

5:06that become specialized because they're

5:08making a matrix. Remember, a matrix

5:10includes two things, protein fibers and

5:13ground substance. So, we're describing

5:15this. When we look at the cells of bone,

5:18it only accounts sometimes up to 2 to 3%

5:21of all of the tissue. The rest is what

5:24it makes, which is the matrix. And then

5:26we have a balance of some cells that

5:28help to create a homeostatic balance

5:31during repair and building the bone as

5:34we grow up to 25 years old. So let's

5:37cover these cells. Starting with

5:39mezenyim or mezenymal tissue. Mezenymal

5:43cells are the basic embryionic stem

5:45cells for which all connective tissue

5:48will arise. So anything from our dense

5:51regular connective tissue to our

5:52cartilage. We start out with mezenymal

5:55tissue. We have a basic starting point.

5:58So these are the embryionic stem cells.

6:01Once we learn that we're turning into

6:03bone, meaning there's there's markers in

6:05the DNA that will be activated to say

6:07we're going to be at this place. We're

6:08creating bone. Meenymal tissues will

6:11then turn into the specialized cells

6:13that make bone. So we start with the

6:15stem cells called osteoprogenitor

6:18cells. So messenymal cells turn into

6:22osteoprogenitor cells. Remember the key

6:24term of differentiation that cells

6:27change over time. No different than you

6:29change over time. You go from a baby to

6:31a child to a teenager to adult and you

6:34change as you get older but it's still

6:36you. So mezenymal will change into

6:39osteoprogentor cells. These are now the

6:41stem cells of bone. So we now mature to

6:44where we get to the point to where we're

6:45going to start going through mitosis.

6:48Osteoprogentor cells keep dividing and

6:51eventually will then turn into the cells

6:53that actually do the work. So

6:55osteoprogentor cells are still stem

6:58cells, but they're specific to bone.

7:00They will turn into osteoblast.

7:03Osteoblasts are the young cells, the

7:06baby cells for B and blast, B for baby.

7:09Osteoblasts are the ones that are going

7:11to secrete the matrix. So, they're

7:13actively doing something and creating

7:15the foundation. To me, it's like

7:17creating the house. It's the people that

7:18live in the house that are building it.

7:21There's only a couple people living in

7:22the big house that they're building.

7:24Remember, we said bone cells account for

7:26only sometimes 2 to 3% of all the bone

7:28depending on the bone. Osteoblasts get

7:31older and become osteocytes and they

7:34help maintain the matrix. Remember

7:36osteoblasts as they get older and they

7:38become sightes they now form that bubble

7:41around it called the lacun. So

7:44osteocytes and lacuna. So now you have

7:46two cells. The younger cells secrete the

7:49matrix. Osteocytes are the ones that

7:51help maintain it. Now we finally get to

7:54the point to where all that

7:56differentiation occurred and you have

7:58actual bone material. Now I put this in

8:02red for osteoclass.

8:04Osteoclass come from what we call

8:06macrofasages. Remember luccoytes are

8:09white blood cells. These are

8:11macrofasages. Macrofasages engulf and

8:14eat things. And so osteoclass with the C

8:17what they do is they break down bone

8:20which is helpful when I break a bone and

8:22help to repair and remodel it. So in

8:24theory it goes back to the same shape.

8:26Remember in a previous video we talked

8:28about long short irregular flat the

8:30types of bone. So based on the DNA it

8:33knows how to regrow it to the same

8:35shape. And when we look at osteoclass

8:37they help for as the bone develops over

8:40time. When my bone grows, it's getting

8:43bigger and bigger. So, if I think about

8:45my femur, the biggest bone in the body,

8:47when I go from 10 years old to 20 years

8:49old, it's increasing dramatically in

8:51size. To help support the bone, I got to

8:54make sure there's enough inside material

8:57to make it function. So, the diameter

9:00will increase, but then I have to allow

9:02room for it to develop. So, osteoclass

9:05will help create that room. And

9:07specifically, they're breaking down the

9:09inside to allow more structural support.

9:12So, intuitively, that seems off. But if

9:14I'm going to build the house and I keep

9:17adding the walls to it, I'm going to

9:19need to do more inside the house and

9:21specifically give me more more room for

9:23it to function. If the body needs

9:26calcium, osteioclass will break down

9:29some of the bone to demineralize it and

9:31take some of that calcium and put it in

9:33the bloodstream. So osteoclass is a

9:35homeostatic balance and it helps us to

9:38create the bones, remodel it, provide

9:40that calcium in the body when need it.

9:43And so we're finally at that point to

9:44create that balance and let's get into

9:46the matrix. So the matrix remember is

9:49made by osteoblast. So osteoblast

9:52secrete the matrix. Our matrix includes

9:55two things protein fibers and ground

9:58substance. protein fibers. Three types,

10:01collagen, elastic, and reticular.

10:05Up to a third of all the matrix is

10:07including our collagen fibers. Remember,

10:10collagen fibers are the most abundant

10:12and they're the strongest to give us

10:14tensile strength. So, these protein

10:16fibers help with that supportive

10:19flexibility.

10:21And then the ground substance is the

10:23material. Remember, it could be a fluid,

10:24it could be gelatinous, it can be hard.

10:26In this case, it's hard like bone.

10:28Calcium is our primary mineral that we

10:31use. Calcium phosphate, calcium

10:33carbonate are the primary compounds that

10:35we see in bone. Phosphate is a strong

10:39material that helps with compression. We

10:41see phosphate in the enamel of our

10:43teeth. Calcium phosphate is one of the

10:45hardest materials in our body because

10:47it's got to support that compression.

10:49Think about my teeth. As I'm constantly

10:51chewing, it supports that compression as

10:53I squeeze onto my carrot that I'm

10:55eating. Calcium carbonate similar to

10:58what's in an egg. So when you think

10:59about an egg, it's got a lot of calcium

11:01carbonate to it. So we see other species

11:03were similar in structure and function,

11:05how we do things. So I have the fibers

11:08that provide that flexibility, ground

11:10substance to help support that

11:11compression. So this all of this

11:14contains majority of what you see in

11:17bone and the body can keep rebuilding

11:19it. Remember we said that in epithelial

11:22tissue we said it does the most

11:24regeneration that I keep rebuilding this

11:26over and over again. All of my epidermis

11:29can regrow in a month. Bones still grow

11:32and repair itself and we know that when

11:33we break our bone but a lot of our

11:35skeleton is completely remodeled and

11:38replaced every 7 to 10 years depending

11:40on your health status, genetics. But as

11:42I get older that'll slow down. But we

11:44keep rebuilding it to create that

11:46strength because it's the structural

11:48support of our body. This is the makeup

11:50of bone. We're covering bone regions and

11:53structures and specifically doing this

11:55from a long bone. This long bone they

11:57have in this picture is a humorris. And

12:00we'll start with just the basic regions.

12:02And so a lot of it just understanding

12:03the terminology as we describe some

12:07different areas in structures of the

12:08bone. We have regions at the ends called

12:12the epiphosis.

12:14Plural is aes so e s. So epiphosis is

12:18the regions where we have the ends of

12:20the bones. And then I notice I put

12:23proximal and distal because we use our

12:25directional terms to understand where

12:28it's connecting. Remember proximal is

12:29closest to that attachment point. Distal

12:32is furthest away. In the middle I have

12:35the shaft or the diaphosis which is the

12:38majority of the long bone. What I don't

12:40have listed here and some texts don't

12:42talk about too much is the metaphysis.

12:44So if you notice here I put a little gap

12:47here but this is the metaphysis and

12:50metaphysis is where we have this

12:52epiphysial plate. Epiphysal plate is

12:56where I have that growth. When we talk

12:58about oifications there's two types of

13:00bone development intramebranus and

13:02endocchondrial. Endocchondrial means

13:04within cartilage and we'll come back to

13:06that in a later video. But

13:08endocchondrial is where I have this

13:10strip of highin cartilage. As the bone

13:13is developing, we're stacking high and

13:15cartilage plates together. That's called

13:17the epiphysial plate. When it's done

13:20growing, it forms bone and then it's

13:22called epiphysial line. So, it's the

13:24same thing, a line and plate. It just

13:26depends on the point of development. So,

13:28that's where the metaphysis is. You may

13:31also see the term surgical neck that the

13:34neck here is called the surgical neck

13:36referring to from the medical side of

13:38breaking a bone. So we have our regions

13:41our plates and then when we look at the

13:44type of tissue type of tissue for bone

13:47oius tissue is spongy and compact in the

13:50epiphyses I tend to see more spongy bone

13:54so the type of tissue in this region of

13:58the epiphosis is spongy bone and it's

14:00spongy because it's porous and I may not

14:03be able to see through it but it's got

14:05holes to it just like the sponge on the

14:07kitchen sink that you have I can't see

14:09through the sponge, but I know water is

14:11going to go through it. Same thing with

14:13bone. One of our primary functions is

14:15blood formation. So, we'll see blood

14:17fill within these spaces or pores of the

14:20spongy bone versus as I come down

14:23towards the diaphosis, I see more

14:26compact bone. So, compact bone gives us

14:29that compression strength as we use the

14:32bone for our movement and leverage. So,

14:35two types of tissue. And then when we

14:38look at the outside of the bone, the

14:40outside layer of this fibrous connective

14:42tissue is called the perryostium.

14:45Perry towards a periphery oium referring

14:47to bone. So it's the outside layer of

14:50the bone. As it's developing, we call it

14:52perchondrium because we'll see cartilage

14:54turn into bone. So perryioium is the

14:57outside lining. What I don't have listed

15:00here is indostium. Indoium is the tissue

15:03that'll line everything inside the bone.

15:06And we'll come back to that when we do

15:07atologology of spongy bone. So I have

15:10three regions epiphosis, diaphosis

15:13and metaphysis. And then we talk about

15:15two layers that help create it.

15:17Perryostium on the outside, indo

15:20indostium on the inside. And then I have

15:23spongy bone and compact bone. Two types

15:26of tissue. We see blood inside the

15:28spongy bone. Within this space of the

15:31diaphosis, it's called the medularary

15:34cavity or the marrow cavity. And that

15:37marrow cavity is our yellow bone marrow.

15:40So it's yellow for a reason because it's

15:41made up of atapose tissue or lipids. So

15:44it's energy supply as we need it. So

15:47within the shaft I see fat, atapost

15:51tissue. Within the epiphosis I see

15:54blood. So I use this a way not only to

15:57support the bone but also support the

16:00body if it's needed. And then lastly

16:02when I look on the outside here it's

16:04showing nutrient arteries. So I have

16:06arteries that help to attach to the

16:08perryostium and this is helping to feed

16:11the bone. We're taking blood out of it

16:13but also during growth and development

16:15we bring in these supplies because

16:17remember bones can reproduce themselves

16:19and regenerate not as fast as other

16:21tissues but roughly every 7 to 10 years.

16:24This whole bone will be redone over and

16:27over again throughout your lifetime if

16:28you live long enough. On the top here, I

16:32have what's called articular cartilage.

16:34So, we'll see articular cartilage.

16:36Remember, three types of cartilage.

16:37Highland elastic and fibroartilage. This

16:41is hyelin cartilage. Highland cartilage

16:44is one of our weaker cartilage for

16:46strength, but it provides a lot of good

16:49support during movement. So, I can move

16:51my shoulder over and over again. And

16:53remember cartilage doesn't have a blood

16:54supply. It doesn't have a nerve supply.

16:56So it makes it easy as I'm using it when

16:59I have a bone that's constantly in

17:01motion over the period of my lifetime.

17:03So articular cartilage is high

17:06cartilage. So we have our regions, we

17:08have our type of tissues compact and

17:10spongy. We have layers perryostium and

17:14osteium. So a lot of it's understanding

17:16our terminology as we learn these

17:18structures and regions of a long bone.

17:20There's two types of bone or oius

17:23tissue, spongy bone, and compact bone.

17:27How do we get to this point? There's

17:28four types of tissue in the body.

17:30Epithelial, connective, muscle, and

17:33nervous. When we look at connective

17:35tissue, there's three types of

17:36connective tissue. Connective tissue

17:38proper. We have three types of dense and

17:40three types of loose. Connective tissue

17:43fluid, which is my blood and my lymph.

17:45And then connective tissue that's

17:47supporting. So supporting connective

17:49tissue is cartilage and bone. Three

17:51types of cartilage, elastic, hyelin, and

17:54fibroartilage. Now we're looking at

17:56bone. Two specific types. Spongy and

17:59compact. They tell you what they are by

18:02their appearance. Spongy is spongy like

18:05the sponge on your sink when you're

18:07washing dishes. That it's porous. That

18:09allows something to go through it. I

18:11can't see through it, but I know the the

18:13water and the soap will go through it.

18:15And that's similar to we see blood and

18:17bones that we fill this area with blood

18:19versus compact is now solid more like

18:22the wall to give me the structural

18:24support. So it's more densely packed

18:26cells. When we look at the model here,

18:29this is referring to an osteon model and

18:31then it's got spongy bone to it. So as

18:35we look at the outer cover, remember

18:37that dense fibrous connective tissue is

18:39the perryostium. So this is the outside

18:42of the bone, the perryostium. And as I

18:44move inward, then we're looking at

18:47compact bone. So this is all compact.

18:50And then once it gets to where it's more

18:52like appearance of a sponge, this is

18:54spongy bone. So let's first look at the

18:56compact bone. When I look at compact

18:59bone, it's organized into a bunch of

19:02functional units that we call an oion.

19:04So each of these circles in circles

19:07within circles are called oons. And you

19:10can see when I pull one up and it's

19:12going the length of a long bone that the

19:15way the fibers move is it crosses this

19:18way and then it twists this way and this

19:20twists this way. So that complimentary

19:22structure how it changes every circle

19:25within it the direction it's going gives

19:27me that shock compression strength for

19:30the bone. So when I look at one osteon,

19:34what we're showing here is it's got a

19:36middle section here to where I have

19:38blood supply, lymph, nerve supply. This

19:41is called the central canal or

19:42herversion canal. So it's bringing in

19:44all the supplies. So on the side here,

19:46they're showing one that's opened up

19:48because we're constantly using this for

19:50blood formation and moving materials

19:53throughout our body. Bones are very

19:55useful for structure support, but

19:56there's a lot of things that are moving

19:58in and out. So when I look at the

20:00central canal then it expands out and

20:02you can see it's a circle within a

20:04circle within a circle within a circle.

20:07Those are called concentric lama and

20:10it's basically how they've been building

20:12and they'll circle around each other

20:13with the blood supply to keep forming

20:15those circles. This gives me an osteon.

20:18And the cells around it, what I try to

20:20indicate with those dark dots are the

20:22osteocytes or osteocytes that would be

20:25in a bubble called the lacun. And the

20:27way they interconnect are these little

20:29lines here. And these little lines are

20:31called canaliculi. Little canals

20:34canaliculi

20:36that help connect cell to cell. So it's

20:38that communication point to where we can

20:41expand and use this as way to move

20:42materials.

20:44And when I look on the sides, you can

20:46see the strength what's left over from

20:48building my osteons. These lines are

20:52called interstitial lamlet. Interstitial

20:55lamlet. So it's the way it's been formed

20:58to give me the structural support for

21:00compact bone. When I pull over and look

21:03at the slide, when I look at this, this

21:05is one nice central canal. That dark dot

21:08in the center. Central canal. Central

21:11canal. So those are indicating my

21:13oonons. So if I look at one oion, it's

21:17got a circle within a circle within a

21:19circle within a circle. Hard to see it

21:21on the histology, but some are better if

21:24we go on a higher magnification, but I

21:25can see almost it looks like a tree

21:27trunk or a dart board to where it's just

21:29a circle within a circle. These dark

21:31dots that circle around, these are all

21:34my osteocytes and the lacun and they're

21:37connected with all these faint lines and

21:39they look like eyelashes or sun rays but

21:42they're real faint through here and

21:43these are all the canaliculi and as I

21:45create these circles these are

21:47concentric lamite. I put all these oons

21:50together and I'm getting compact bone

21:53versus when we pull over to spongy bone.

21:57Spongy bone we tend to see more in the

21:59epiphosis and compact bone we see more

22:02in the diaphosis for that strength. So

22:05spongy bone is porous. So if I show on

22:08this slide here, it's these pinkish

22:11rivers here and it's a lower

22:13magnification, but I'm looking at the

22:15spongy nature of it. The darker purple

22:18inside is some of our blood or blood

22:20marrow or red bone marrow that fills in

22:23those spaces. Just like I talked about

22:25the sponge at your sink that we're

22:27filling those spaces for a reason. So

22:29when I look at the lighter pink rivers,

22:31this is all spongy bone that's been

22:34formed. So if we went on a higher

22:36magnification in the middle, I would see

22:39osteocytes and they would be in the

22:41lacun, the bubble that houses them.

22:43Towards the edge of the tissue, I'm

22:45going to see more osteoblasts because

22:48they're contributing to the formation of

22:50all of these structures that we call

22:52tvicula. So I have osteoblast the cells

22:55towards the edge in the middle. I know

22:58it's we have to go on a hard

22:59magification to see that but the cells

23:01the tiny little dots through here these

23:03are osteocytes in the middle. They're

23:05helping to form the spicules which are

23:07the little struts that form the spicules

23:09which are the little struts that give me

23:11tbvic which is the functional piece of

23:14spongy bone. So all of these little

23:17pieces are these pink pieces here. So

23:19the difference between spongy and

23:21compact is not a location. Same chemical

23:23composition. It's just how they're

23:25created and developed. So when I see my

23:27tree trunks, I know I'm looking at

23:29compact bone. When I see these pink

23:31rivers with the blood in between, I know

23:33I'm looking at spongy bone. Two types of

23:36oius tissue. We're covering bone

23:38development or oifications.

23:41As we learn how we get to understand our

23:43matrix of bone and we develop bone

23:46there's two types of ocification which

23:48is a bone development intramebranous and

23:51endocchondrial. We're just going to

23:53describe the difference between the two

23:55and then we'll have more videos talking

23:57about them independently. But when bone

24:00forms that's called osteogenesis

24:03which is bone formation. And then once

24:06it forms it can start to grow. We grow

24:08bones in two ways. in width which is a

24:11posositional growth and then in length

24:14which is interstitial growth. But we

24:16can't grow until we have the materials

24:18to develop it so it can grow. To me bone

24:21development is this process of

24:23ocification. We bring in the right

24:25materials which means the right cells to

24:28then create the right matrix to give us

24:30what we need to develop bone. Because

24:31remember bone is only sometimes 2 to 3%

24:35of cells. It's what they develop and

24:37make to form the bone that creates the

24:39actual product that you see as a bone.

24:42So two types of oification intramebranus

24:45and endocchondrial. Intramebranus is

24:48referring to within a membrane and we

24:50refer to this for dermal bone. So we say

24:52dermal like closer to the skin. So it's

24:54bones that I can when I think about

24:56intramebrous it's what I can feel. So I

24:58can feel my mandible. I can feel my

25:01frontal bone, my praa bone. Those are

25:03bones that I can actually touch and feel

25:05my clavicle. They're right at the skin

25:07dermal bones. And we call intrammebrous

25:10ocification within membranes. And we'll

25:13talk about those membranes, but it's

25:15referring to these types of dermal

25:16bones. More of a simpler process of bone

25:19development versus endocchondrial is

25:21within cartilage and specifically it's

25:24hyelin cartilage that we use it as a

25:27model. And what happens is when we talk

25:29about oification the actual definition

25:32is taking one tissue and replacing it

25:34with another. In intramebrous we take

25:37mezenyal tissue and turn it into bone

25:40and we use the cells to make bone

25:43osteoblast and then our osteoccytes to

25:45maintain it. When we look at

25:46endocchondrial we're taking first

25:49mezenymal tissue and then turning into

25:52highin cartilage to create a building

25:54block to then turn that into bone. And

25:57this can take years in many cases

25:59depending on the bone somewhere up to 25

26:02years for endocchondrial usually

26:04referring to long bones. So as we look

26:07at this let's just talk about when we

26:09talk about intramebrous

26:11this the picture here is matching the

26:13microscope slide down here but we're

26:14basically saying is I have a top sheet

26:17of mezenymal tissue and then a bottom

26:20sheet. So it's in between two sheets of

26:22tissue. Remember meenchymal tissue is

26:26our stem cells or embryionic tissue for

26:29which all connected tissue arises. So

26:31mezenymal tissue is that basic tissue

26:34that then it differentiates and turns to

26:36other types of cells to give me the

26:39final product. In this case we're

26:40talking about bone. So we'll see two

26:43sheets, one here and one here of

26:46mezenymal tissue that'll gradually

26:49migrate and change with the blood supply

26:51to give me the actual structure of bone.

26:55How do we do that? Well, the mezenymal

26:57cells turn into osteoblasts. Some books

27:00will say, well you also see

27:01osteoprogenitor cells, which we'll talk

27:03about that in the next video, but it

27:05turns it into bone because the cells

27:08change. And because the cells change,

27:10their function changes. And what are

27:12they doing? They're secretreting the

27:13matrix, which is that osteoid to where

27:16you're getting the calcification.

27:18Calcification is creating the

27:20mineralization of the bone specifically

27:22using calcium, calcium phosphate,

27:24calcium carbonate. So I look down below

27:27here. This dark purple is trying to show

27:29you the formation of bone. And you could

27:31start to see that it's looking more like

27:33spongy bone. So we're turning this into

27:36spongy bone. And then on the top I have

27:38a membrane sheet of tissue that mechmal

27:41tissue and then also here on the bottom.

27:44So in between two membrane sheets I'm

27:46creating this type of bone and it occurs

27:49in dermal bones versus when we look at

27:52endocchondrial this is showing you a

27:54long bone. So a lot of our long bones go

27:56through this process to where they're

27:58using now hyelin cartilage to where we

28:01occur at the epiphysial plate. So this

28:04section here at the epiphosis and then

28:08the diaphosis there's a section in

28:10between there a region called the

28:11metaphysis

28:13and this is where I have highland

28:15cartilage this is matching on this side

28:18to where there's different zones on how

28:20it develops but basically you're going

28:22to have hypertrophy or dying off of

28:24cartilage cells and where do those cells

28:26come from we start with mezenymal then

28:28it turns into hyelin cartilage so we're

28:31using condro blast and condondroytes

28:34to use this as stacking cells. So they

28:36call it a pipal plate because it's

28:39literally like we're stacking plates of

28:41cartilage that will then be replaced by

28:43bone. We're taking one tissue and

28:44turning into another. That's an

28:46oification.

28:48So once we're done growing depending on

28:50the bone like I said this could take

28:52years it turns into epiphysal line. So

28:55epiphysal plate and line is at the point

28:58in development. A plate is when it's

28:59growing. A line is when it's f finally

29:02done. So for example, some bones take a

29:04couple decades for them to actually

29:06finish their product. So we see is a

29:08difference here is that highland

29:11cartilage model that we're using and

29:13then it starts to turn into bone. So

29:15when I look at the dark purple over here

29:17for spongy bone that's forming these

29:19dark little purple sections here. So

29:21it's very baby spongy bone that we're

29:23looking at. So intramebrance and

29:25endocchondrial oifications

29:27is understanding how do we get to the

29:29final product of bone. We use our cells

29:31to create the matrix. But we can't do

29:33that without a foundation. We both start

29:36with mezenymal tissue. And then it just

29:38depends on where we're at which bone.

29:40Are we just using mezzenyal turn into

29:42osteoblast osteoccytes or we using

29:44hyelin cartilage as a model? This is

29:47intramebrous and endocchondrial

29:49oification. In the next couple videos,

29:51we'll break down the two and just go the

29:53order of the steps of the cells and how

29:55they differentiate. This is

29:57intramebranous oification which is bone

29:59development. So we're discussing just

30:01this type. In a previous video we

30:04briefly compared the difference between

30:06intramebranus

30:07and endocchondrial oification. Remember

30:11this is bone development and we're

30:12taking one tissue and turning into

30:14another. We see that throughout the

30:16course of our body in different parts

30:18that things change and specialize.

30:20That's differentiation. Our body has the

30:22ability to change from one cell to the

30:24next for the purpose of creating some

30:27type of product. In this case, it's

30:29both. When we talk about intramembranous

30:32oification, it's in between membrane

30:35bones, dermal bones. We discussed that

30:37it's part of like the mandible, some of

30:39my bones of my cranium, my clavicle.

30:42These are dermal bones that I can feel

30:44right through my skin. How they develop

30:48is starting with meenymal tissue. So in

30:50the previous video we looked at the same

30:52pictures but it's good to highlight

30:53what's happening here that this picture

30:56is describing this picture and it's a

30:58point in time of the development but

31:00essentially we have mezenymal tissue

31:03which is our basic stem cells. So what

31:05is mezenymal tissue? It's our stem cells

31:09or basic embryionic tissue for which all

31:11connective tissue arises. In other

31:13words, mezenyal tissue can turn into

31:15other types of tissue just besides bone

31:17or cartilage. it could turn into things

31:19like connective tissue proper dense and

31:22loose. So as we describe this we're

31:24specifically looking how do we form our

31:26two types of oius tissue remember that's

31:29spongy and compact bone. So what are our

31:31two types of oius tissue spongy and

31:34compact bone but we got to get to that

31:36point we got to be able to develop it

31:38and then they got to grow. So how they

31:41develop is through intramebrous

31:43oification when we talk about our dermal

31:45bones. So we start here with a sheet of

31:48mezenymal tissue and a sheet of

31:50mezenymal tissue and we're bringing in

31:52blood supply. Remember one of our

31:54functions of bone is blood formation but

31:56it's also heavily used for the

31:57development of bone to bring in the

31:59supplies we need for it to develop. And

32:01that's why I think of bone development

32:03is bring in the supplies and then it can

32:05grow. So we start with mezenymal tissue

32:08and usually two sheets of it to where

32:10the mesenymal cells are migrating but

32:13they start to change or differentiate

32:15into osteoblasts.

32:17Remember you also have osteoprogenitor

32:21cells which are then the stem cells of

32:23bone. So depending on the text sometimes

32:25messenymal will turn into

32:27osteoprogenitor

32:28and then osteoblast. You'll see some

32:31text that'll say it'll go straight for

32:32meal and skip osteoprogentor straight to

32:35osteoblast. But you still have the

32:37presence of osteoporoggenitor

32:39cells. Those are the stem cells for bone

32:42itself. So we go from mezenymal to

32:45blast. Remember baby cells for the bead

32:48blasts are the ones secretreting the

32:50matrix because we know that majority of

32:52the bone is actually what the cells are

32:54secretreting which is the matrix. That

32:56includes our protein fibers primarily

32:59collagen fibers because we have three

33:01types. You remember those three types

33:03collagen, elastic and reticular.

33:06Collagen is for our strength. So we use

33:08it for bone and it's the most abundant

33:10fibers. So osteoblast is secretreting

33:13the matrix of collagen fibers but then

33:16also includes that osteoid that compound

33:19that creates the ground substance. and

33:21we start to mineralize the bone and we

33:23do that through calcium. So

33:26calcification occurs as well to give us

33:29the mass that hardened material which is

33:31calcium phosphate calcium carbonate

33:34primarily. So that was a lot to say just

33:36what's going on with osteoblast but

33:38meenymal cells differentiate and turn

33:41into osteoblast to actually secrete the

33:43matrix. Remember this is occurring

33:46within now this purple area because this

33:49is the start development of bone

33:50specifically spongy bone. So those

33:54osteoblasts will continue to secrete the

33:56matrix. Remember as they get older they

33:58turn into osteocytes and they tend to

34:00form a little bubble around them called

34:02a lacun. So osteoblasts turn into

34:06osteoccytes to help maintain the tissue.

34:08Once I have these cells, I'm creating

34:11that product. And we call this spicules

34:13or tbicula. Spicules is a basic little

34:16branch that starts and as it all

34:18branches together like a tree, it

34:21becomes tbvicula. So if I just took

34:23little pieces of this in segments like

34:25this is a spicule that combines with a

34:27spicule. Here's another little strut

34:29here, a spicule, and it just starts

34:31forming all together, which is called

34:33turbicula. So you might use those terms

34:35interchangeably in some text. spicules

34:38turn into tbvicula. Once I have that

34:41final branching, now I can start to form

34:43my two tops types of oius tissue,

34:46spongy, and then it could continue to

34:48develop and turn into compact bone

34:50depending on where we're at in the bone

34:52and what type of bone it is. So it's

34:54just the basic steps but it's the key is

34:56understanding that it's the the change

34:59that we are replacing one type of tissue

35:01mezenymal tissue and with our blood

35:04supply to bring in the actual cells

35:06that'll turn into the bone making

35:09process of intramebrous ocification. So

35:12as soon as I see the difference between

35:14the two from intramebranus I just see

35:17two sheets of tissue versus when we look

35:20at endocchondrial endocchondrial

35:22oification is our next video and that's

35:24seeing highin cartilage. So we compare

35:26the two slides I'm really just looking

35:28for the bubbling of cartilage cells that

35:31we'll look at in the next video. This is

35:33intramebranus oification. This is

35:36endocchondrial oification.

35:39Endocchondrial is referring within

35:41cartilage. We looked at intramebranous

35:44ocification in a previous video to where

35:46it's within membranes of mezenymal

35:48tissue. And in endocchondrial we still

35:51use mezenymal tissue. We just add an

35:53extra step of using highland cartilage.

35:56This is often confusing for students

35:58because it's like what the heck are we

36:00talking about here? This is about how we

36:02develop bone because remember we said

36:05once we get into connective tissue we

36:06see a lot more in the spaces the

36:09interstitial spaces of cells of what the

36:12cells are making and this is the matrix.

36:14So as we develop bone we're taking one

36:18tissue and turning it into another.

36:20That's an ocification. In this case

36:22we're using cartilage high and

36:24cartilage. So what this slide is trying

36:26to show you is that when we look at long

36:28bones we tend to see more highland

36:32cartilage and the point here where this

36:34arrow is and I magnified it on this side

36:37this is our epiphysial plate and there's

36:39different zones on how we categorize the

36:42development of it I'm just going to

36:43focus on where we have this hypertrophy

36:46or the building in in larger cells of

36:49highland cartilage cells specifically

36:52condroytes that start to bubble up And

36:54then we're going to replace them with

36:56osteoblasts and osteoccytes because

36:58they're the ones that make the matrix.

37:00So remember as refer to a long bone,

37:03we're going in this development here to

37:05where we we build or develop first in

37:08the diaphosis which is the shaft and

37:11we'll call that the primary oification

37:13center. And as we gradually build out,

37:16we're building into the epiphosis or

37:18epiphyses which is the secondary

37:20oification center. And where we stack

37:23then that cartilage is in the epiphysial

37:26plate. So epiphysial plate is that point

37:29of development. As it fully develops

37:32sometimes up to 20 25 years then it

37:34becomes an epiphysial line and forms

37:36bone. So as we describe this and we just

37:40started with the basics of cartilage in

37:43the embryionic development of bones

37:45within our first six weeks inside the

37:47womb as a fetus. We're all cartilage and

37:50we're gradually changing into bone where

37:52it's needed because the cells become

37:55specialized. They differentiate. In this

37:57case, when we look at a long bone, we

37:59see a lot of cartilage and we're

38:01starting in this developmental process

38:04in the middle, which is the primary

38:06oification center. And what we're doing

38:08is mineralizing the bone at the same

38:10time. And how do we do that? We do it

38:12with calcium. Calcium phosphate, calcium

38:14carbonate. That's the mineralization or

38:17calcification of bone. So what this is

38:20saying is we're going to bring in the

38:22materials to help the bone grow. So it

38:26mentions perchondrium up here. This is

38:29referring to the outside layer of the

38:31bone which is cartilage to start. Later

38:34it becomes the perryostium

38:36which is referring to now that it's bone

38:38towards the outside.

38:40So now we go from paricondum to

38:42perryioium. We're building in this

38:45primary oification center and it

38:47gradually then going to bring in blood

38:49supply to start to build in our

38:51secondary oification center which is

38:54then the epiphosis. So what's happening

38:56here is we start with our basic

38:58embryionic cells are stem cells which

39:00are mezenymal cells. They will turn into

39:03the cells that help to make bone. You'll

39:06see osteoprogenitor cells which are stem

39:09cells for bone specifically. they turn

39:11into osteoblasts and osteoblasts are the

39:15ones that are starting to secrete the

39:17matrix and when we see that that's

39:19coming through the blood supply to take

39:21over that cartilage that we built. So

39:24this is where we start to see that

39:26epiphysial plate that's building as a

39:30long bone. And when that epiphysial

39:33plate continues to grow, we just stack

39:36cartilage cells. And the specific

39:38cartilage cells are my condo sites. And

39:41those condo sites, we go through what's

39:43called aertrophy or hypertrophy. They

39:45get larger and larger and die off. And

39:47we replace them with the bone cell. So

39:49what you're seeing here is from this

39:51growth plate, all this dark purple here

39:54is starting the formation of basically

39:56baby bone. And you can see it looks

39:58somewhat porous. It's forming spongy

40:01bone and then it'll gradually turn into

40:04compact bone where needed. So we go

40:06through messenymal cells. They turn into

40:09cartilage. So condond condro blasts

40:11condondroytes because those are the

40:13cells that make my highland cartilage.

40:15We take over that highland cartilage

40:17model. So we built the framework for the

40:20bone but would then we replace it with

40:21osteoblast and osteoccytes to secrete

40:24the bony matrix. There's two types of

40:26tissue that we're trying to develop

40:28spongy bone and compact bone. So that's

40:32the big difference with endocchondrial.

40:34We see it in long bones and we're using

40:36a highland cartilage model. When I look

40:38at intramembranous

40:40slide I don't see this stacking in the

40:43bulgy condondroytes. So when you're

40:45looking at histologology just process

40:48elimination I'm trying to find that

40:50cartilage model first if I don't see it

40:53then I know I'm looking at intramebranus

40:55this is endocchondrial oification the

40:57development of bone specifically for

40:59long bones we're going to cover some of

41:01our cranial bones and then we'll look at

41:03the sutures associated with cranial

41:05bones and then move on to facial bones.

41:07So when we look at our cranial bones,

41:09there's eight bones total, but only six

41:11terms because two of the bones have two

41:15of them. So as we cover the frontal

41:17bone, we start with just the frontal

41:19side. So our forehead is our frontal

41:21bone. That's number one. Over the top,

41:24we have two parietal bones. Parietal

41:28bones. As they go posterior, oipital

41:32bone. I tried to outline it here for

41:34you. This is occipital bone. And then on

41:37the sides I have a temporal bone where

41:40my ear is temporal bone. And then same

41:43thing on the other side. Temporal bone.

41:46When I look inside the skull, we're

41:48going to look at ethmoid and spinoid.

41:52And I'm going to turn it this way. This

41:53is anterior. Tried to highlight this

41:56best I could. But the green here, this

41:58is the part of the ethmoid bone, one of

42:01our pneumatized bones. And then where I

42:04drew the purple that's creating the

42:07boundary there, this is the spinoid

42:09bone. Spinoid bone. So eight bones total

42:12when we look at our cranial bone. One

42:15frontal parietal two and three occipital

42:19on the back four. My temporal five and

42:23six. And when I open it up and look

42:26inside our cranial fossas at the floor

42:29here, ethmoid 7, sphenoid 8. So our

42:33eight cranial bones. Let's look at some

42:36of the sutural bones. This is dense

42:38fibrous connective tissue to connect our

42:40bones together. So these sutures that

42:43come across. First we'll start with as

42:46it creates this boundary to connect my

42:49frontal my pietals. This is the coronal

42:52suture. So coronal suture just like we

42:56cover sections or planes a sagittal cut

42:59this is the sagittal suture. So we did

43:02coronal sagittal. As I come to the

43:05posterior side with the oipital bone

43:08this outline here this is all lambdoid

43:12lambdoid or lamoidal suture. And then on

43:16the sides where I see my temporal bone

43:19this is squamus or squamosal suture. So,

43:22squamus suture. So, as we cover the

43:25sutures, they're combining to the bones.

43:28Now that we've talked about the cranial

43:29bones, let's look at some of the bony

43:31landmarks or bony markings of those

43:34bones. So, when we look at our frontal

43:37bone, inside is the frontal sinus. So, I

43:40need a sagittal cut to see that. As I

43:42come across and look at the posterior

43:45side and we go back to our occipital

43:47bone, some of our bony markings, if I

43:49look at this bulge here, this little

43:52projection is called the external

43:54occipital protuberance. External

43:56occipital protuberance. And we'll attach

43:58a ligament there that's called the nucal

44:00ligament associated with lip lash. So

44:02this is the external occupants.

44:05Coming off of it on either side is this

44:08line superior nucal line. Superior nucal

44:13line external occipital protuberance

44:16superior nucal line. Then below there's

44:20an inferior nucal line that's underneath

44:23or inferior to my superior. And then as

44:26I run down this is my

44:30oipital crest. Oipital median crest.

44:34occipital median crest. This will lead

44:37down to this big hole that we call the

44:40fam and magnets. Fammens are holes. It's

44:43a larger hole magnus. So framin magnum.

44:46So the hole there for our brain stem is

44:48famin magnum. On either side I have a

44:52smooth projection here on either side of

44:55fram and magnum. This is called oipital

44:58condiles. Oipital condiles is the

45:01attachment for the C1 vertebrae which is

45:03called my atlas. We say yes I love

45:06learning this stuff. So oipital

45:09condiles

45:11when we look at our temporal bone

45:13temporal bone when we look at right or

45:15left I'm using this projection here

45:17which is a process and this is called

45:19the zygomatic process and to me it's

45:22almost like you're using as a like a

45:24Bluetooth microphone. That's how I can

45:27tell right or left with this. But this

45:29is all temporal bone. That projection

45:32coming off is zygomatic process because

45:35it leads to my zygomatic bone. When I

45:38look at other projections, I have two

45:41more processes that we'll learn. This

45:43big one is a mass. This is called the

45:45mastoid process. Mastoid process.

45:50And then just like a stylus you have for

45:52an iPad or some of our phones, this

45:54projection that comes underneath,

45:57if you can see it there, that looks like

46:00a a stylus or a pen. Styloid process. So

46:05styloid process, mastoid process where I

46:10can pick my ear and I put my hole in the

46:12ear where the sound travels in. So when

46:14I hear things this is external acoustic

46:18miatus also called external auditory

46:21canal. External acoustic miatus or

46:24external auditory canal. When I open it

46:27up and I look inside I have these big

46:31bulges here. And so all of this

46:35is called the petrus part or petrus

46:37portion. This petrus part is where I

46:40hold all my inner ear structures for

46:42hearing my cookia and balance and

46:45equilibrium. So all my inner ear

46:47structures are housed inside here to

46:50protect it. This is called the petrus

46:52part. Another bony marking of the

46:54temporal bone. When I look at the

46:57ethmoid bone

47:00part of it I can see sticking out on the

47:02anterior cranial fossa here. this space.

47:05The other part of it is inside the nasal

47:08cavity. So this bone sits right in here.

47:11When I look at this whole middle plate

47:14here, that's called the nasal septum.

47:16It's a general term to describe two

47:19bones coming together. But the top half

47:21of this is called the perpendicular

47:25plate. The perpendicular plate is one of

47:27our bony markings of the ethmoid bone.

47:30So the top half is perpendicular plate.

47:34it'll come up and combine

47:37with some of our structures here that's

47:39still part of the ethmoid bone. So as I

47:41turn it this way, there's a projection

47:44here that kind of looks like a shark's

47:46fin. And this is called the crisali. The

47:49crisali that projection that sticks up

47:52crisal. The crisali sits on what we call

47:56a cribopform plate. A cribopform plate.

47:59The cristagali sits on the cribopform

48:01plate. So this is really small because

48:04this is all just the ethmoid bone just

48:06in this area where that crystal galley

48:09sits is on either side where I have the

48:12curbopform plate. And what's unique

48:14about it is I'll have if the pipe

48:16cleaner was my nerve my oldactory nerves

48:20for smell sit on either side of this.

48:22I'll you also use the cristy galley for

48:25some of our menenes attachments for dura

48:28modder. But when I look at my cribopform

48:31plate, it has holes in it. And those

48:33holes are called olfactory foramina.

48:37Framins are holes. Plural is framina.

48:40Olactory foramina. So when I breathe and

48:44I smell the molecules of whatever I'm

48:46breathing in, it's going to go through

48:47the nasal cavity through those olfactory

48:50foramina and stimulate the olfactory

48:52nerve. So I have cristagali

48:55which means crest of the rooster.

48:58And then cribopform plate is what it

49:02sits on on either side. And then the

49:04holes within the cribopform plate are

49:07all factory foramina. Now I look at the

49:10sphinoid bone which I said was part of

49:13the the floor of the middle cranial

49:15fossa. When I look at the sphinoid bone

49:18I can see that it has what's called

49:19lesser wings and greater wings. The

49:22lesser wings

49:24are at the anterior side here. So lesser

49:28wings at the top and when you look at

49:30the bone disarticulated

49:32it looks like the antlers of a bat. So

49:36this is lesser wings. The rest of this

49:41is greater wings. So greater wings

49:45and then the small lesser wings. What's

49:48going through the lesser wings is the

49:50optic canal. as I put my pipe cleaner

49:55through the holes of the lesser wing.

50:01So, I have the pipe cleaner going

50:03through the holes of the lesser wing.

50:05And that lesser wing has that hole for

50:08one specific reason. It's called the

50:10optic canal. So, the optic canal

50:14is for the eyeball. So, I'm using the

50:17optic nerve, pretend my pink pipe

50:19cleaner is my optic nerve to connect to

50:22my eyeball. So, going through the lesser

50:24wing, there's a hole called the optic

50:27canal. And so, as you're studying this,

50:29write that in your notes that it's the

50:31hole in the lesser wing. In between my

50:34two wings,

50:37lesser and greater, I have what's called

50:40the superior orbital fissure. So in

50:44between my wings I have a gap and that's

50:46called a fissure. Superior orbital

50:50fissure. And so when I show it this way

50:52it's another for blood vessels and

50:54nerves. But this attachment and I'm

50:57going to pull out the optic nerve. So

51:02then you can see that space in between

51:05is superior orbital fissure.

51:08So two holes there right at the lesser

51:10wings and the greater wings. And then I

51:12have this cradle here. We call this the

51:16celotica, which means Turkish saddle.

51:20And it's curved like a sea. And what

51:22it's supposed to do is I'm going to use

51:24this slime. And I'm just going to put it

51:27inside here to show you how I can sit

51:31seat the pituitary gland. So one of our

51:33glands, pituitary gland, sits in the

51:36celotica.

51:38So that space as I take this out is

51:42celotica

51:44and it's literally like a a bed or a

51:46crib or a cradle to hold

51:51my pituitary gland. Okay. And then we're

51:54going to learn three holes coming off

51:57the greater wing. So three holes in the

51:59greater wing are called forammen

52:01rotundum, framino valley and fammen

52:04spinosum.

52:07When I look here, three holes. This

52:10first hole is called fammen rotundum.

52:14And this will repeat on both sides in

52:16the greater wing. But frammen rotundum.

52:18And then I have frammen ovali.

52:22And then right below it I have frammen

52:25spinosum. So there's three holes that

52:27run on the sides through the greater

52:29wings. And we always have these holes

52:31for something. It's either blood supply,

52:33nerve supply, or both. So famin

52:36rotundum, framino valley and fammen

52:39spinosum.

52:41I covered that a little bit with the

52:43purple but that is spinosum. So if you

52:45can see three holes there I just

52:48remember ros

52:50rotundum o valley spinosum. So three

52:54holes that we look at. The other thing

52:56is when I go through the the feet of the

53:00spinoid bone, it's like kind of like

53:02looking at the bat underneath

53:05it sticks out on either side. This is

53:08called the terragoid process. Terragoid

53:11process. And it's just these little

53:13sections of the bone. And when I show

53:15you this picture, you can kind of see

53:18how it sits inside the cranium. But

53:22those projections that come underneath

53:27tragoid process with the silent P. And

53:30now we're covering facial bones. So all

53:32of our facial bones and then we'll look

53:34at some of the actual landmarks

53:36associated with those bony landmarks

53:39within the bones. And then also we'll

53:41look at the eye socket. The eye sockets

53:43actually seven bones. In our next video,

53:46we'll describe those seven bones that

53:48make up the bony orbit or the orbital

53:51complex. So, when we look at our facial

53:53bones, part of it makes up the eye

53:54socket. And what we'll look at is we

53:57already covered frontal bone. Then we

53:59move on to nasal bones. So, the bridge

54:02of my nose is nasal bone. The rest of it

54:06is mostly cartilage. This is my nasal

54:08bone. In between the two nasal bones is

54:12where I have a suture called the

54:13interasal suture. And then coming up

54:17that runs across this is frontto nasal

54:22suture. Front nasal suture because it's

54:25connecting nasal bones to the frontal.

54:27And then very light but just that little

54:31squiggly line there. This is frontal

54:33suture also called mtopic suture. So

54:36this is frontal suture running across

54:40like it's an upside down T

54:43frontto nasal suture and then interasal

54:47suture in between my nasal bones. So I

54:50look at I have my nasal bones when I

54:52come inside the eye

54:56just this little small area here is the

54:59lacrial bone and it's where your tears

55:02come out when you're crying when you got

55:03to learn all this stuff. This is called

55:05the lacrial bone.

55:08And lacrimal bone

55:11will help as we produce tears here and

55:13it rolls across my eyes. It'll fill up

55:15in in a duct here that we'll talk about

55:17later. But where that occurs, it's so

55:20small. The bony landmark is pretty much

55:23all of the bone and it's called the

55:25lacrial sulcus or the lacrial groove. So

55:28this is my lacrial bone, but the

55:30landmark is the lacrial groove. So when

55:33we talk about identifying things is it

55:35the bone versus the bony marking it

55:37depends on how it's asked. So the

55:39landmark is the lacrimal sulcus.

55:43When I come down and we look at my

55:45cheek, this is zygomatic bone. Zygomatic

55:49and zygomatic bone has a process here

55:52that's called the temporal process. And

55:55the temporal process connects to the

55:58temporal bone, but it's connecting by

56:00way of the zygomatic process of the

56:03temporal bone. That should be confusing

56:05the first time I say it. The two bones

56:08come together, zygomatic bone and

56:10temporal bone. Those create what we call

56:13the zygomatic arch which is that nice

56:16curve of the cheek. What we're

56:18describing are the two bony landmarks

56:20that are coming together. So the process

56:23is the opposite of the bone. So if this

56:25is zygometic bone and I divide all of

56:28this in just half. This anterior portion

56:31is called the temporal process. The

56:34other side is the zygomatic process.

56:37That's part of the temporal bone. So

56:39zygomatic bone temporal bone the

56:42processes are the opposite zygomatic

56:44process temporal process

56:47as I come down then where I grow a

56:50mustache and it'll come up along the

56:52sides of the nasal bone this is all max

56:54or maxillary bone max or maxillary bone

56:59and then I also have the vulmer bone the

57:02vulmer previously we talked about the

57:04nasal septum which is that whole middle

57:06sheath that whole middle sheath is the

57:09nasal septum but the top half of this

57:12sheath is the perpendicular plate of the

57:15ethmoid bone. The bottom half is the

57:18vulmer. Those two come together to

57:21become the nasal septum. If they break

57:22or they don't fuse together straight,

57:24it's called a deviated septum. The other

57:27thing we can see inside which is its own

57:30separate bone

57:32is the inferior nasal conci. So on

57:36either side this fold just on the bottom

57:39here and here is inferior nasal conci.

57:45And so we also have middle and superior

57:48that are part of the ethmoid bone on the

57:50picture that I'll show in the video. You

57:52can see that a little bit better. But as

57:54I describe all these folds inside,

57:56they're called conci. So it's everything

57:58besides the nasal septum. As I breathe,

58:01it creates a turbulence to help clean,

58:03warm and humidify the air in preparation

58:05for respiration. So I look inside the

58:09bottom folds on either side inferior

58:11nasal coni. The bone that comes down

58:14here the project is the vulmer and we

58:18were leading to then the mustache bone

58:20is the maxillary bone which also

58:23includes the roof of the mouth on the

58:26anterior side. So this is anterior. the

58:30roof of the mouth.

58:32This is all still the maxillary bone,

58:35but the bony marking is called the

58:37palatine process. The palletine process.

58:40As I go to the posterior, then we see

58:43the palatine bone. So I highlighted that

58:46with green there, palatine bone. So this

58:49can be confusing because the anterior

58:51portion is the maxillary bone. The

58:55posterior bone is the palatine bone. The

58:58actual name of the landmark or bony

59:00marking is the palatine process. So I

59:03have two bones that really are creating

59:05that roof of the mouth. When I look at

59:07the teeth and we see where the teeth are

59:09coming together, but I have these

59:11projections and not the teeth itself,

59:13but these are called alvolar process.

59:15These are alvolar parts. So we'll often

59:18see alvolar parts is just referring

59:20these little projections that help

59:21create that socket for the teeth to go

59:23into. we'll see part of the maxillary

59:25bone, but then when we see it on the

59:27mandible. So, let's get into the

59:29mandible. As I look at my jaw or my

59:31mandible, it's really just a nice L and

59:35it just repeats on both sides. So, when

59:37I describe the L, the mandibular ramis

59:40is the first part of the L and then the

59:43body is continuing on with the letter L.

59:46So, mandibular ramis, mandibular body.

59:50When I look at the projections that are

59:53up at the top here, the one that

59:56connects into the temporal bone, it's

59:58connecting into the mandibular fossa of

1:00:01the temporal bone. You see a little bit

1:00:03of cartilage there. It's actually

1:00:05fibroartilage for that shock

1:00:06compression, but it's going to sit

1:00:09inside there. What I'm describing is the

1:00:12condular process. So this is the

1:00:14condular process that's going to go into

1:00:17the mandibular fossa. On the anterior

1:00:20side it's called the coronoid

1:00:23process. So two processes condular

1:00:26process coronoid process but it's the

1:00:30condular process that goes into the

1:00:33temporal bone

1:00:35at that mandibular fossa. As I come down

1:00:38we see this mental protuberance.

1:00:42This is referring just how the jaw comes

1:00:44out here. Mental protuberance. And then

1:00:47I have two holes here which are called

1:00:50mental frammens. Remember holes are

1:00:53forammens. And I actually use that for

1:00:55remember holes are not just holes. We

1:00:57put something in there that's extensions

1:00:59of nerves. So I can feel that. So these

1:01:01holes in front are mental frame. We're

1:01:04covering the bony orbit or the orbital

1:01:07complex or the eye socket. We talked

1:01:10about some of our different cranial

1:01:11bones and facial bones. This is just a

1:01:13conceptual idea that the seven bones

1:01:15that make up the bony orbit fuse

1:01:18together to give me what holds my eye.

1:01:20So, we're describing just those. And I

1:01:22tried to color this the best I can, but

1:01:24this red circle as I pull it into this

1:01:28black circle, we're describing those

1:01:30bones that come together. So, there's

1:01:32seven bones. frontal, zygomatic,

1:01:34maxillary, spinoid, palatine, ethmoid,

1:01:38and lacrimal. Those fuse together to

1:01:40give me what's called my bony orbit. So

1:01:42frontal bone, which is my forehead,

1:01:45contributes down to my cheekbone, my

1:01:47zygomatic bone. We learned spinoid bone

1:01:50that makes up part of my middle cranial

1:01:52fossa, the floor inside when I open up

1:01:54the skull. And then also the same with

1:01:57ethmoid as we get towards the anterior

1:01:59cranial fossa. Remember ethmoid has that

1:02:01perpendicular plate and part of that

1:02:04will come down and stick out here with

1:02:06my nasal conci. My lacrimal bone is

1:02:10where my tears develop. So just on the

1:02:12corner of my eye here. So I get lacrial

1:02:15bone, ethmoid bone and palletine bone.

1:02:17And then down to my maxillary bone which

1:02:20is my mustache bone and part of the roof

1:02:23of my mouth but it still comes up all

1:02:25the way around my nose. So, we'll often

1:02:28use a pneumonic for these. You'll see

1:02:30different ones out there. I prefer you

1:02:32just learn the bones, but one I see

1:02:35students use is called please feed my

1:02:38zebra, but please spelled incorrectly.

1:02:42It's spelled as ple.

1:02:44So, the ple means palatine, lacrial,

1:02:48ethmoid, and spinoid. And then, so I

1:02:50said please feed just the f is my

1:02:54frontal. My the M is maxillary and zebra

1:02:59Z is a zygomatic. Sometimes not a fan of

1:03:02pneumonics as we've seen in previous

1:03:03video because now you're learning

1:03:04something completely different that's

1:03:06not associated with the I at all but

1:03:08some students like using them. So please

1:03:10feed my zebra but please is spelled P L

1:03:13E S. This is how you can remember the

1:03:15seven bones but you're already learning

1:03:18them independently.

1:03:20So this is just a concept of

1:03:22understanding the bony orbit or the

1:03:24orbital complex is how these seven bones

1:03:26fuse together to give me one distinct

1:03:28area to hold my eye. We're covering the

1:03:31vertebrae and we'll start by comparing

1:03:33the differences between cervical,

1:03:36thoracic, and lumbar just so we can tell

1:03:38the differences between them because in

1:03:41most exams or tests they ask them

1:03:43separately. So let's look at this. As we

1:03:46describe the three and we put them

1:03:48together, we can tell by size. This is a

1:03:51cervical vertebrae. This is a thoracic

1:03:54vertebrae. And this is a lumbar

1:03:57vertebrae. Now, just doing

1:03:59procelumination, the best way I can

1:04:01determine that I have a cervical is when

1:04:03I look inside, there's actually three

1:04:06holes that make up a cervical vertebrae.

1:04:10And what's unique to them are these

1:04:12holes that are in my transverse process.

1:04:15And these are called transverse

1:04:18foramina. Transverse forramina. These

1:04:21are unique to cervical ver vertebrae

1:04:23that I don't see in my thoracic

1:04:28or my lumbar.

1:04:30So just by pro elimination I could

1:04:32already determine is it cervical or not.

1:04:35And some of the cervical vertebrae, not

1:04:36all of them, but the on their spinus

1:04:40process, you can see these two little

1:04:42projections. That's called a bifid

1:04:44spinus process. That there's two heads

1:04:47coming off of it. Versus when I look at

1:04:49the other two types, thoracic

1:04:53and lumbar, they don't have those spinus

1:04:56processes that project two different

1:04:58pieces. So I can already rule out a

1:05:01cervical once I look at those two holes

1:05:04again which are transverse framina. When

1:05:06I compare

1:05:09thoracic versus lumbar the easiest way

1:05:11for me is when I look at the the hole in

1:05:14the center which is called the vertebral

1:05:16frammen. Remember frammans are holes. So

1:05:20that hole in the middle on the left this

1:05:23one's a thoracic and it's a nice circle.

1:05:26When I look at a lumbar, it's a

1:05:30triangle. So, I can compare the two just

1:05:32by that hole. The other thing I just

1:05:34look at is the design of it. When I look

1:05:37at the centrum or the body, it appears

1:05:39to have a heart shape for the body

1:05:42versus cervical and lumbar. I don't see

1:05:46that same heart shape. The other thing I

1:05:48just look at is just a general

1:05:50description of it. A lot of my students

1:05:51will say a thoracic looks like a giraffe

1:05:55or an elephant as if this was the

1:05:58elephant's trunk, which is the spinus

1:06:00process, versus a lumbar tends to look

1:06:04like a moose. So, I just go by these

1:06:07blunt processes and the appearance of it

1:06:09that a lumbar tends to look like a

1:06:11moose. Now as I get into the different

1:06:14structures, one thing to notice when we

1:06:17identify our processes that the spinus

1:06:20process is our further posterior

1:06:23structure bony landmark that this

1:06:27spinus process is always going to point

1:06:30down. This spinus process is always

1:06:32going to point down. And so we look at

1:06:35our spinus processes. These are the

1:06:37further posterior bony landmarks of each

1:06:41vertebrae. When I look at the sides as

1:06:44if it's like the wings,

1:06:47these are transverse

1:06:49processes. So transverse processes.

1:06:52Transverse process. Transverse process.

1:06:55Transverse process and a transverse

1:06:57process.

1:06:59When I look at a cervical, I know I have

1:07:02a transverse process. And that's because

1:07:04it has holes inside. Remember those are

1:07:07called transverse veramina which are

1:07:09unique to a cervical vertebrae. Now when

1:07:12I looked to how we create the actual

1:07:15vertebral arch and the circle around it.

1:07:18So as I go around and create this all

1:07:22these bony landmarks what we're

1:07:23describing first is all of them have

1:07:25this but as I look at the sententrum or

1:07:28the body I describe these as like

1:07:30bridges. So in order to get from the

1:07:33body or sentrum to the transverse

1:07:36process, I go through just this little

1:07:39bridge called a pedacle. A pedacle. And

1:07:42this is very small and difficult for

1:07:44students at first, but I just imagine as

1:07:46if I'm to drive from here to here, my

1:07:49body to my transverse process. I drive

1:07:52along this pedacle. In order to get from

1:07:58transverse process to what I'm holding

1:08:00is the spinus process. This bridge is

1:08:03called the lamina or lamina. So as I go

1:08:06from body

1:08:09to transverse process I have this little

1:08:12connection called a pedacle. In order to

1:08:14get from transverse process to spinus

1:08:16process I go through the lamina.

1:08:20So I'm describing those bridges. Now,

1:08:23how do I connect the vertebrae? What we

1:08:26use are called articular facets. And

1:08:28what I'm showing here is I'm going to

1:08:30take a couple thoracic and put them

1:08:32together. And where they're connecting

1:08:35are on these flat sections of the bone.

1:08:38And so where I'm sliding, these are

1:08:40called articular facets. And so when I

1:08:43look at it, to me, I described as if I'm

1:08:45holding my hand up with my arm. The flat

1:08:49smooth side of this

1:08:52is called the superior articular facets.

1:08:56So it's like the ears of the elephant.

1:08:59So superior articular facets and it's

1:09:04that smooth hand that's being held up by

1:09:07the arm. The arm behind it is the

1:09:10process superior articular process holds

1:09:14up the flat hand. Superior articular

1:09:16facet. So I'm using the superiors to

1:09:20attach to the inferior. So as I flip it,

1:09:23these superior tricular facets now

1:09:26appear flat on this side because this is

1:09:29the inferior articular facet. And what

1:09:33holds it up is the arm, the inferior

1:09:37articular process. So I'm using my

1:09:40processes and my facets to come together

1:09:44and they come together at those facets.

1:09:47So on top I'm using inferior articular

1:09:50facets to connect to my superior

1:09:53articular facets.

1:09:55The other unique thing about a thoracic

1:09:59vertebrae as I describe these is we're

1:10:02connecting ribs. So on my ribs I'm going

1:10:05to use my vertebral end of my ribs to

1:10:08connect to these little projections

1:10:10here, here, and here. This is superior

1:10:14costal faucet. This is inferior costal

1:10:18faucet and then on the transverse

1:10:20process that divot is transverse

1:10:23costtoal facet. So I can flip it on the

1:10:26other side too. The depression on the

1:10:28transverse process

1:10:31transverse costal faucet

1:10:34inferior costal faucet

1:10:36and superior costal faucet. Those are

1:10:40only unique to a thoracic vertebrae

1:10:44versus all the other bones have those

1:10:47other structures or bony markings that

1:10:49we learn. So transverse process, spinus

1:10:52process, superior articular facet behind

1:10:56it is the superior articular process for

1:10:59team forammen and body. So we can desri

1:11:02describe all the same for all three.

1:11:06When we look at how we describe our

1:11:10cervical vertebrae, what's unique to

1:11:12them

1:11:13is the first two and number seven. So

1:11:16now I'm going to show you

1:11:19one, two, and then we're going to get

1:11:22all the way down to seven. C7 because I

1:11:25have seven ser cervical vertebrae, 12

1:11:27thoracic, and five lumbar. This flattest

1:11:32one here, these are all cervical

1:11:34vertebrae. And how do I know that? This

1:11:36flat one still has transverse foramina.

1:11:40But it also has the widest vertebral

1:11:43forammen out of all of them. And that's

1:11:45because it's C1, also known as the

1:11:48atlas. And this is the vertebrae that

1:11:50helps us to say yes. And so I'm using

1:11:53these

1:11:55articular facets to actually connect to

1:11:57the occipital condiles of the occipital

1:12:01bone. So I have atlas which is my

1:12:05flattest

1:12:07bone and we look at it's got those wide

1:12:09features to it but it's flat versus

1:12:12number two or C2 cervical vertebrae is

1:12:16called the axis. So atlas and axis

1:12:21remember T becomes before X. So atlas

1:12:24helps to me to say yes. Axis helps me to

1:12:28say no. Now, what do I mean by that is

1:12:31that when I put the vertebrae on, we're

1:12:33going to use it to swivel to be able to

1:12:36say, "No, I don't want to learn this

1:12:38stuff." Or, "Yes, I do enjoy learning

1:12:40this stuff." How do I know this is

1:12:44axis? A lot of students will say it

1:12:46looks like Buddha and this is Buddha's

1:12:48head. And Buddha's head is called the

1:12:51dens, also known as the adontoid

1:12:54process. So, dens or adontoid process.

1:12:58And this is how I identify what's unique

1:13:00for all of our cervical vertebrae as C2

1:13:04the axis. And then lastly, we said our

1:13:07last vertebrae for cervical is C7.

1:13:10What's unique about C7? It starts to

1:13:12transform almost looking like thoracic

1:13:14where I have that long slender spinus

1:13:16process. But this spinus process is

1:13:19unique because we're going to attach a

1:13:22ligament here. We call this the

1:13:24vertebrae prominence. And this is going

1:13:27to attach one of our ligaments that goes

1:13:29to our cipal bone. So when we experience

1:13:32whiplash, it's impacting the cervical

1:13:35vertebrae. But we have more attachment

1:13:38points because we have a lot more

1:13:39movement in our cervical vertebrae. So

1:13:41that's a description of how we

1:13:43understand our different vertebrae.

1:13:46And then as we come down from lumbar,

1:13:50we're going to get to the sacrum. So,

1:13:52our last

1:13:56vertebrae, our number five lumbar is

1:13:58going to attach

1:14:00to my sacrum.

1:14:03And then after that, I'll attach the

1:14:07coxix. So, when we look at this now,

1:14:10we're describing how we have multiple

1:14:12landmarks for the sacrum and then the

1:14:14coxix. So the sacrum is five bones that

1:14:19have fused together versus the coxix or

1:14:23coxyal bone can be three to five. And

1:14:26typically we teach it as four but it

1:14:29varies on the person. In this case we're

1:14:31seeing four bones. When we look at the

1:14:33sacrum we're going to use this to attach

1:14:36as part of our pelvic girdle to the

1:14:38coxal bone. So, as we describe it, I'll

1:14:41show you it still has that weightbearing

1:14:43part of the centrum of the body. As they

1:14:46come down, we actually end up having

1:14:49some of our spinal nerve endings coming

1:14:51through what's called the sacral canal.

1:14:54and it'll go all the way down and

1:14:55there's a hole here called the sacral

1:14:57hiatus

1:14:59because the spinal cord ends around

1:15:01lumbar one lumbar 2 vertebrae and then

1:15:04it starts to expand in what we call the

1:15:06kada eina which means horse's tail. So

1:15:10when you look at a picture of you'll

1:15:11have all these nerve endings that are

1:15:13going down here to stay protected in a

1:15:15sacral canal but then you'll end up with

1:15:18still a hole that ends up here called

1:15:20the sacro hiatus.

1:15:22Along the sides you'll see more holes

1:15:26and these are called sacral

1:15:29framina. Remember frammans are whole

1:15:31plural is framina sacral framina. And

1:15:35then down the middle you'll see the

1:15:38median sacrum crest. Median sacral

1:15:41crest. And this is trying to show you

1:15:43all the spinus processes of those five

1:15:46bones that have fused together. So

1:15:49median sacral crest are foramina sacral

1:15:52foramina. And then on the sides I have a

1:15:56uricular surface on the lateral sides.

1:15:59Aruricular surface auricular surface.

1:16:03And this is to attach the sacrum. So we

1:16:07have sacrum and coxix. We're covering

1:16:10the bones of the hands and the feet.

1:16:13We're starting with a right hand and

1:16:15we're looking at the palmer view or

1:16:17anterior view in the anatomical

1:16:19position. And we're learning the

1:16:21carpals, the metacarpals, and the

1:16:23fanges. We'll start with our carpals.

1:16:26And in our wrist, we have eight bones.

1:16:28The way I teach this is with a pneumonic

1:16:31to start lateral and count four bones

1:16:34over to the medial side and then go back

1:16:36to the lateral side with four. We use

1:16:39the pneumonic so long to pinky.

1:16:45Here comes the thumb. So as we learn

1:16:49this, the first one that's the most

1:16:52proximal is scaffoid. And it's kind of

1:16:55shaped like an S. So I remember the S in

1:16:58scaffoid scaffoid

1:17:01lunate

1:17:02triquetum and we could see triquetum

1:17:05when we turn it. This is triricquetum

1:17:08and on top is pa form. So long to pinky.

1:17:15And now I continue back with the next

1:17:17four. Here comes the thumb. Hamate,

1:17:23capitate,

1:17:26trapezoid,

1:17:28and trapezium.

1:17:30Hamate, capitate,

1:17:32trapezoid, trapezium. Students tend to

1:17:35get these two last ones confused. I just

1:17:38remember that the D becomes before M and

1:17:40trapezoid

1:17:42and trapezium.

1:17:44Scaffoid, lunate, triquetum.

1:17:48Pisa form is the rock on top. Hamate,

1:17:53capitate,

1:17:54trapezoid, trapezium.

1:17:58Now to our metacarpals

1:18:011, two, three, and four and five

1:18:03metacarpals. Now we add the number

1:18:06number one metacarpal. Number two,

1:18:08number three, number four, number five.

1:18:11These are all my metacarpals. I just

1:18:13remember the big guys number one the

1:18:17thumb and the big toe are number one. So

1:18:19metacarpals

1:18:22to my digits or fanges.

1:18:24For the finger we call it the pollix.

1:18:27It's got two bones to it. It's got a

1:18:29proximal fangi and a distal fangi. So

1:18:33two bones. The rest of my fanges

1:18:36have a proximal middle distal. proximal,

1:18:40middle, distal, proximal, middle,

1:18:42distal. Now we can name them with the

1:18:44number one, two, three, four, and five

1:18:48plus its designation of proximal middle

1:18:50distal. And then it's a fangi.

1:18:53So this would be number three

1:18:57proximal fangi. This would be number

1:19:00four, middle fangi. This would be number

1:19:04five, distal fangi. This is my hand.

1:19:09When we look at the foot,

1:19:12this is a right foot. And we'll start

1:19:15with our seven tarscels, then the

1:19:18metatarscils, and then back to fanges.

1:19:21There's seven toarsils. Some students

1:19:24like to learn it with the pneumonic. I

1:19:26like to just learn the terms in this

1:19:28case because I think they're bigger

1:19:29bones, easier to learn as you study

1:19:32them.

1:19:34The big one which is the heel is the

1:19:37calccanous.

1:19:38So it's the heel what I step back on

1:19:41dorsal flexion and I have the calccanous

1:19:45on top. T for top this is all the talis

1:19:50and it curves here and it looks like

1:19:52more than one bone from here to here.

1:19:55This is all the talis.

1:19:58Calccanous

1:20:00and talis. Running across

1:20:04is nvicular.

1:20:07Calccanous. Talis. Novicular. And then I

1:20:11have one, two, and three ununiforms.

1:20:16I have a medial ununiform, intermediate

1:20:19ununiform, and a lateral ununiform. And

1:20:23then lastly on the lateral side, the one

1:20:25that's supposed to look like a cube.

1:20:26This is cub boy. So seven tarscels

1:20:30calccanous

1:20:32talis

1:20:35running across nvicular

1:20:38one two and three ununiforms

1:20:41medial intermediate and lateral

1:20:44ununiforms cuboid.

1:20:47Similar to the hand now we count our

1:20:49metatarscils except we go the opposite

1:20:51direction. Remember we said thumb and

1:20:53big toe are number one. So this would be

1:20:56one metatarsal, two, three, four and

1:21:00five metatarscils. My fanges

1:21:04for the toe we call the thumb the

1:21:07pollix. For the toe we call it the

1:21:10holix. Two bones just like the thumb.

1:21:13It's got a proximal distal fangi. For my

1:21:16toes,

1:21:18one, two, and three. Proximal, middle,

1:21:21distal. Proximal, middle, distal.

1:21:24Proximal, middle, distal, proximal,

1:21:25middle, and distal. Counting the

1:21:28numbers, this would be number two,

1:21:30proximal fangi. This would be number

1:21:33three, middle fangi. This would be

1:21:36number four, distal fangi. This is my

1:21:39foot. We're covering the bones of the

1:21:41hands and the feet. We're starting with

1:21:44a right hand and we're looking at the

1:21:46palmer view or anterior view in the

1:21:49anatomical position. And we're learning

1:21:51the carpals, the metacarpals, and the

1:21:53fanges. We'll start with our carpals.

1:21:56And in our wrist, we have eight bones.

1:21:59The way I teach this is with a pneumonic

1:22:01to start lateral and count four bones

1:22:04over to the medial side. And then go

1:22:07back to the lateral side with four. We

1:22:09use the pneumonic. So long to pinky.

1:22:16Here comes the thumb. So as we learn

1:22:20this, the first one that's the most

1:22:22proximal is scaffoid and it's kind of

1:22:25shaped like an S. So I remember the S in

1:22:28scaffoid scaffoid

1:22:31lunate

1:22:33triquetum and we could see triquetum

1:22:35when we turn it. This is triricquetum

1:22:38and on top is pa form. So long to pinky.

1:22:46And now I continue back with the next

1:22:48four. Here comes the thumb. Hamate,

1:22:54capitate,

1:22:56trapezoid,

1:22:58and trapezium.

1:23:00Hamate, capitate, trapezoid, trapezium.

1:23:04Students tend to get these two last ones

1:23:07confused. I just remember that the D

1:23:09becomes before M and trapezoid

1:23:12and trapezium.

1:23:14Scaffoid, lunate, triquetrum.

1:23:18Pa form is the rock on top. Hamate,

1:23:23capitate,

1:23:25trapezoid, trapezium.

1:23:28Now to our metacarpals.

1:23:311 2 3 and four and five metacarpals. Now

1:23:35we add the number number one metacarpal

1:23:38number two number three number four

1:23:40number five. These are all my

1:23:42metacarpals. I just remember the big

1:23:46guys number one the thumb and the big

1:23:48toe are number one. So metacarpals

1:23:52to my digits or fanges. For the finger

1:23:55we call it the pollix. It's got two

1:23:58bones to it. It's got a proximal fangi

1:24:01and a distal fangi. So two bones. The

1:24:04rest of my fanges

1:24:06have a proximal middle distal. proximal,

1:24:10middle, distal, proximal, middle,

1:24:12distal. Now we can name them with the

1:24:15number one, two, three, four, and five.

1:24:18Plus its designation of proximal,

1:24:20middle, distal. And then it's a fangi.

1:24:24So this would be number three,

1:24:27proximal fangi. This would be number

1:24:31four, middle fangi. This would be number

1:24:34five, distal fangi. This is my hand.

1:24:39When we look at the foot,

1:24:42this is a right foot. And we'll start

1:24:45with our seven tarscels, then the

1:24:48metatarscils, and then back to fanges.

1:24:52There's seven toarsils. Some students

1:24:54like to learn it with the pneumonic. I

1:24:56like to just learn the terms in this

1:24:58case because I think they're bigger

1:25:00bones, easier to learn as you study

1:25:03them.

1:25:04The big one which is the heel is the

1:25:07calccanous.

1:25:08So it's the heel what I step back on

1:25:11dorsal flexion and I have the calccanous

1:25:15on top. T for top this is all the talis

1:25:20and it curves here and it looks like

1:25:22more than one bone from here to here.

1:25:25This is all the talis.

1:25:28calccanous

1:25:30and talis running across

1:25:34is nvicular.

1:25:37Calccanous talis nvicular and then I

1:25:41have one, two and three ununiforms.

1:25:46I have a medial ununiform, intermediate

1:25:50ununiform, and a lateral ununiform. And

1:25:53then lastly on the lateral side, the one

1:25:55that's supposed to look like a cube,

1:25:57this is cuboid.

1:25:59So seven toarsils calccanous

1:26:03talis

1:26:05running across novicular

1:26:08one, two and three uniforms,

1:26:11medial, intermediate, and lateral

1:26:14uniforms. Cub boy

1:26:17similar to the hand. Now we count our

1:26:20metatarsils except we go the opposite

1:26:21direction. Remember we said thumb and

1:26:24big toe are number one. So this would be

1:26:26one metatarsal. Two, three, four and

1:26:30five metatarscils. My fanges.

1:26:34For the toe we call the thumb the

1:26:38pollix. For the toe we call it the

1:26:40holix. Two bones just like the thumb.

1:26:43It's got a proximal and distal fangi.

1:26:46For my toes

1:26:48one, two, and three. Proximal, middle,

1:26:52distal, proximal, middle, distal,

1:26:54proximal, middle, distal, proximal,

1:26:56middle, and distal. Counting the

1:26:58numbers, this would be number two,

1:27:00proximal fangi. This would be number

1:27:03three, middle fangi. This would be

1:27:06number four, distal fangi. This is my

1:27:09foot. We're covering the skeletal

1:27:11system. I'm going to mix the axillary

1:27:14and the appendicular system. We're going

1:27:16to start out with the sternum and then

1:27:18we're going to work our way all the way

1:27:19down to the arm. One of our previous

1:27:21videos, we looked at hands and feet. So,

1:27:23let's just start with the sternum. We

1:27:26can divide it into three sections. From

1:27:29my pointer up, this is all the

1:27:31manubrium. And then the bottom or distal

1:27:34portion is called the zyphoid process.

1:27:36Zyphoid means sword. Manubrium means

1:27:39handle. So, the handle is the manubrium.

1:27:42Everything in between the manubrium and

1:27:45the zyphoid process is the body. So I

1:27:48have three regions. Manubrium,

1:27:50body, zyoid process. Couple other

1:27:53landmarks or bony landmarks to learn. On

1:27:56the top this ridge here on top is called

1:27:59the jugular notch. So jugular notch on

1:28:03the sides for the clavicle clavvicular

1:28:06notches. So clavvicular notch, jugular

1:28:10notch. And then where the cartilage is

1:28:13connecting for the ribs, these are all

1:28:16costal notches. Costal referring to the

1:28:18ribs. So costal notches. Keep in mind

1:28:21this is not bone. This is cartilage.

1:28:23What type of cartilage is this? Remember

1:28:25there's three types of cartilage.

1:28:27Highland, fibrous, and elastic. This is

1:28:29highin cartilage. So this is the

1:28:31sternum.

1:28:33As we move on to a rib and connecting

1:28:37the rib, I have two ends that we're

1:28:40learning. The smoother end is referring

1:28:43to the sternal end because we're going

1:28:45to get that connection to the cartilage

1:28:48of the sternum. So sternal end is my

1:28:51smooth end. My rougher end where I have

1:28:54these projections is the vertebral end.

1:28:56So two ends, vertebral end and sternal

1:29:00end. couple of the landmarks that we'll

1:29:02learn. The actual end or the head of the

1:29:05vertebral end is the head and then in

1:29:08between is the neck. So at the vertebral

1:29:12end I have head and neck and then I have

1:29:15a tubacle. So I have this tubacle here.

1:29:19As I come down and I look on the

1:29:21inferior side, the inferior side and

1:29:25when I'm going in the posterior portion

1:29:27of the bone, this is costal groove or

1:29:29sulcus. May be hard to see on the

1:29:32screen, but when you rub your finger

1:29:33through here, you can see a groove. And

1:29:35that's protect some of our nerves and

1:29:36blood supply. And then when I determine

1:29:39right or left on this, remember I said

1:29:41that this is the sternal end. So, it's

1:29:44got to go to the sternum, either here or

1:29:47here. But I need that costal groove to

1:29:51be on the inferior side but also

1:29:54posterior. So this stays down. This has

1:29:57to go to my vertebral end. So this is a

1:29:59right rib if you can imagine it on my

1:30:01bottom. So right rib.

1:30:04As we move on to the clavicle. This is

1:30:08our collar bone but now we call it the

1:30:10clavicle. And when we look at this, the

1:30:13top part of it or superior part is

1:30:16smooth relative to the inferior portion.

1:30:20As we learn the inferior portion, that's

1:30:21where we identify a couple of our bony

1:30:23markings. Again, two ends. I have what's

1:30:27coming to the sternum. This is the

1:30:29sternal end. And this is the acromian

1:30:32end. And the chrom chromial end looks

1:30:34like a spoon to me. And it'll look like

1:30:37that on the scapula, too. So as I come

1:30:39down to the sternal end, this is going

1:30:41to connect to the sternum either like

1:30:43this or like this. And so sternal end

1:30:47acchromial end. So two ends. And when I

1:30:50turn it on the inferior side at the

1:30:52acromal end, we're learning this

1:30:54projection here which is the conoid

1:30:58tubrical.

1:30:59Conoid tubrical. So it's a little bulge

1:31:03or bump on the inferior side. When I

1:31:06come over to the sternal end, there's a

1:31:08rough projection here called the costal

1:31:11tuberosity. So these can be difficult

1:31:13for students. But as I look at the

1:31:16smooth side is my top or superior. The

1:31:20bottom is my inferior on the acchromial

1:31:22end. We are learning the conoid tubacle

1:31:26and the costal tuberosity is this rough

1:31:29projection as we get close to the

1:31:30sternal end. right or left with this. I

1:31:34use again that the top is my superior

1:31:37side. That's that smooth section. And

1:31:40when I follow the acchromial end, it

1:31:42curves like a spoon. And I want that

1:31:45spoon to project out anterior away from

1:31:48me. This is a right clavicle because I

1:31:50have to put this at the sternal end no

1:31:52matter what I do with this. But as I

1:31:55follow the acchromial end, it comes out

1:31:57and points away. So this is a right. If

1:32:00I turn this this way, the crumblen's

1:32:03going to stab me with that spoon. I

1:32:05don't want that. So, this is a right

1:32:08clavicle

1:32:09because we move on to the scapula or

1:32:13shoulder blade. It's kind of a triangle.

1:32:16So, three sides of a triangle. So, we

1:32:18name those as borders. This is a

1:32:21superior border. This is an axillary or

1:32:25lateral border because it's going to be

1:32:26at my armpit. And I know this is lateral

1:32:29because I have this connection here for

1:32:32my humorris. And that landmark is called

1:32:35the glenoid cavity. So that has to

1:32:38project lateral.

1:32:40And so that glenoid cavity is going to

1:32:42project this way. So I know this is my

1:32:44lateral side or lateral border, also

1:32:47known as axillary because it's my

1:32:48armpit. This is medial border because

1:32:51it's going to be more medial and it's

1:32:53also called the vertebral border because

1:32:55it's closer to the vertebral colum on

1:32:57top superior border. So three sides of

1:33:00the triangle lateral border, superior

1:33:03border and medial border. As I look at

1:33:06these projections, these are processes.

1:33:10And the big one on the posterior side,

1:33:13this end is called the acromian or

1:33:15chromium process. And it's connected to

1:33:18the scapular spine. And this is what you

1:33:21can feel on your posterior side of your

1:33:23back. So scapular spine runs and becomes

1:33:26the acromian process. Scapular spine.

1:33:30Scapular spine. Acromian orchromian

1:33:32process. If you notice, it looks similar

1:33:35to the acromian

1:33:37of the clavicle. So they look similar.

1:33:40So I still have that spoon appearance.

1:33:44Acchromian process. As I turn it and I

1:33:47go back to anterior

1:33:49coroid process, corocoid process. So

1:33:53with the C, you're going to see corocoid

1:33:55acromian process. And then when I look

1:33:59with this scapular spine, I have a space

1:34:02above it called the suprapinus fossa.

1:34:06Below it, infraspinus fossa. So above

1:34:10the spine, supraspinus fossa. Fossas are

1:34:13depressions. Infra below it. So we're

1:34:16learning those two spaces. When I go on

1:34:19the anterior side and to go anterior, I

1:34:22have to go deep. So we go sub or below.

1:34:26This space where I can rub my hand is

1:34:28called the subscapularis fossa.

1:34:31So subscapularis fossa, supraspinus

1:34:35fossa, infraspinus fossa. Why are we

1:34:38learning this? We're building the

1:34:39language. We're going to attach muscles

1:34:40here when we cover muscular system. When

1:34:43we look at that connection again, we

1:34:45said that space is called the glenoid

1:34:47cavity. There's two projections at 12:00

1:34:50and 6:00. One's called the supra glenoid

1:34:54tubrical at the top at the bottom infra

1:34:59glenoid tubrical. So 12 and 6:00 supra

1:35:03glenoid tubrical infra glenoid tubrical.

1:35:07How do I do right or left with this?

1:35:09Remember I said I need that connection

1:35:12for the humorris. So this has to point

1:35:14out either this way or I have to t turn

1:35:18it.

1:35:20It's going to go like that. But this is

1:35:21not going to sit well. When you feel

1:35:24this on your back, that spa subscapular

1:35:28area is going to be deep on my back. But

1:35:31the scapular spine has to point out

1:35:34posterior and I need that connection for

1:35:36the glenoid cavity. So this is a right

1:35:38scapula.

1:35:40Moving on to the humorris. The first

1:35:43thing I wanted to show you is these two

1:35:44colors with the pipe cleaners as we

1:35:46describe some of our necks. The rounded

1:35:49portion where we're going to connect to

1:35:51the glenoid cavity of the scapula is the

1:35:54head. So hummeral head. The neck,

1:35:57there's two different types of necks.

1:35:59When I go around with the pink one just

1:36:01underneath the head, this is called the

1:36:03anatomical neck. The green one is

1:36:06referring to the surgical neck. So two

1:36:09types of necks. Anatomical.

1:36:12surgical. The reason we call it surgical

1:36:14is this is right at the region called

1:36:15the metaphysis where we have the

1:36:17epiphysial plate or the growth plate. So

1:36:20if we have damage or we break a fracture

1:36:22of the bone here, it could end up in

1:36:24surgery. So two necks to learn there.

1:36:27Now as we move on to the rest of the

1:36:29bone,

1:36:31I'm showing you a right. Remember we

1:36:33said this is the head. When I look

1:36:36anterior, this projection on the

1:36:38anterior side is the lesser tubacle.

1:36:42Lesser tubacle. On the lateral side,

1:36:46this big one here is greater tubacle.

1:36:50Greater tubicle. Because of those two

1:36:53tubacles, I have a space in between

1:36:57called the inner tubicular groove or

1:37:00inner tubicular sulcus. So lesser

1:37:03tubicle is more anterior. Greater

1:37:05tubicle is more lateral and then I have

1:37:08that sulcus or groove in between. As I

1:37:11come down the shaft, it'll bow here more

1:37:15on the lateral side and it'll get rough.

1:37:18And that rough portion is for the

1:37:20deltoid muscle. So we call this the

1:37:22deltoid tuberosity. So where it becomes

1:37:25rough and creates somewhat of a bow

1:37:27here, this is called the deltoid

1:37:29tuberosity.

1:37:30As we come down to the distal end, we're

1:37:33learning condiles. And there's four

1:37:36here. One, two, three, and four. So four

1:37:42condiles. As we learn this, these are

1:37:44two epicondiles.

1:37:47Epicondiles towards the edge. On this

1:37:50side, this is the lateral epicondile.

1:37:54The bigger one from here over, this is

1:37:57the medial epicondile.

1:38:00medial epicondile, lateral epicondile,

1:38:03and then the two specific condiles in

1:38:05between. The first one that's rounded

1:38:07like a cap to me remember like a

1:38:10baseball cap and the word cap is in

1:38:12capitulum. So capitulum capitulum

1:38:16and then from here to here all of this

1:38:20is called the troleia. And students will

1:38:22say it looks like two, but it's all one

1:38:24because it grooves down and turns and it

1:38:28looks like it's two. But all of this is

1:38:30troleia and we use that to hinge

1:38:34my ulna inside there.

1:38:37So we'll come back to the ulna but in

1:38:39review lateral epicondile medial

1:38:42epicondile

1:38:43capitulum

1:38:45and then all of this is ta

1:38:48tleia. Two fossas to learn one on front

1:38:52one on back. So on the anterior side

1:38:55coronoid fossa coronoid and we learned

1:38:59coriccoid process of the scapula. So it

1:39:01gets a little crazy on the anterior side

1:39:04coronoid fossa. Posterior the larger one

1:39:07is the electron fossa. Electron fossa

1:39:13right or left with this. I know all of

1:39:15these condiles have to be anterior. So

1:39:19if these are anterior, I need the smooth

1:39:22side of my hummeral head to go into my

1:39:25body on the medial side. So I use this

1:39:28to connect

1:39:30to my scapula. So this is a right. If I

1:39:33put this over here on my left side, now

1:39:35I have this rough greater tubicle that's

1:39:38going to hurt when it moves. So this is

1:39:40a right humorous. So then we look at a

1:39:44ulna, my elbow bone. Remember we said

1:39:48we're taking this and connecting into

1:39:51the troleia. How do we do that? It's

1:39:54through this C here called the tlear

1:39:58notch. Often called semi lunar notch

1:40:00because it's a half moon. So tlear notch

1:40:03because it hins inside the troleia. And

1:40:05how does it do that? Through these two

1:40:07processes. The top one which is

1:40:11essentially my elbow. The electronon

1:40:14process is that projection on the

1:40:16posterior side. On the anterior side we

1:40:20have the coronoid process. Coronoid

1:40:24coronoid process electronon process. So

1:40:28the two processes go into my two fossas.

1:40:32My

1:40:34electronon

1:40:36process is going into my electronon

1:40:39fossa. My coronoid process is going into

1:40:42my coronoid fossa. So they connect

1:40:45together.

1:40:47As I follow the coronoid process of the

1:40:51ulna, to me it looks like it kind of

1:40:53breaks open here. So all of a sudden

1:40:55there's this little ridge here to where

1:40:58it's like a nice circle and then it

1:41:00breaks. It doesn't literally break, but

1:41:01I just imagine that. And that point

1:41:03there is called the radial notch because

1:41:05I'm going to use that to attach the

1:41:09radial head. So the radial head goes in

1:41:12the radial notch of the and that'll help

1:41:15me with right or left. So radial notch

1:41:19as I come down the rough projection

1:41:21going more distal. This is the er

1:41:24tuberosity. So er tuberosity

1:41:29further distal ular head is the rounder

1:41:33portion ular head and then the styloid

1:41:36process ular styloid process. Now this

1:41:39is another styloid process you learned

1:41:41you learned it on the temporal bone as

1:41:43well. So er head ular styloid process.

1:41:46How do I do right or left with this? I

1:41:48said this is the radial notch. So I

1:41:50attach the radius for this in anatomical

1:41:54position. We said my radius is my rad

1:41:57bone on my lateral side in ant position.

1:42:00My pinky side is my ular bone. So if

1:42:03this has to be on the medial side, if I

1:42:06put it on the left, I can't connect my

1:42:09radius because the radial notch is on

1:42:11the wrong side. If I put this on my

1:42:14right side, now I can connect my radius.

1:42:18So this is a right.

1:42:21So if we add to that, here's my radius.

1:42:25The head switch. So now I have the head

1:42:28on the proximal side. So the round head,

1:42:32radial head. As I come distal, this is

1:42:34on the anterior side. This is called the

1:42:37radial tuberosity. So this bulge radial

1:42:41tuberosity. And that's how I connect my

1:42:43biceps brachi. It inserts at the radial

1:42:46tuberosity. So radial tuberosity as they

1:42:50come down to the distal side the

1:42:52furthest projection that bump there is

1:42:54the radial styloid process. So another

1:42:57styloid process and I imagine this kind

1:43:00of looks like my thumb when I place this

1:43:02out.

1:43:04So I use styloid process and then on

1:43:07this side on the medial side I have

1:43:11another groove here and that's called

1:43:13the er notch.

1:43:15ER notch. And why do I have an er

1:43:21head? So as I look at this, I'm using my

1:43:25radial head to connect to my radial

1:43:27notch of the ulna. I'm using my ular

1:43:30head to connect to my notch of the

1:43:33radius. So my heads and notches go

1:43:36together. So we're determining right or

1:43:38left with this. As I come down,

1:43:41I said my radial tuberosity is anterior.

1:43:45So I have to keep this anterior and I

1:43:47just remember again this kind of looks

1:43:48like my thumb in anton position this

1:43:51would stay

1:43:53on the anterior side. So this is a

1:43:56right. If I put this on my left side my

1:43:59styloid process is going the wrong way.

1:44:01So this is a right radius. So here's a

1:44:05quick review. We did manubrium body

1:44:08zyoid process. We learned that our

1:44:11clavicle has two ends, a chromial end

1:44:13and a sternal end. We learned that our

1:44:16scapula has three borders to it. A

1:44:18lateral border, a medial border,

1:44:21superior border. The main projections,

1:44:24corcoid process on the posterior side, a

1:44:27chromian process. I have a glenoid

1:44:29cavity with the super glenoid tubrical,

1:44:32infraenoid tubrical to connect to my

1:44:35humorris. And we said our humorris as I

1:44:38come down has a lesser tubal a greater

1:44:41tubicle with a inner tubicular groove

1:44:44deltoid tuberosity and my condis

1:44:48epicondiles lateral medial capitulum

1:44:52tleia. When I look at my ulna, we said

1:44:57my two processes electron process,

1:45:00coronoid process, trolear notch, radial

1:45:05notch. As I come down, er head, ular

1:45:09styloid process, and to the radius,

1:45:12radial head, radial tuberosity. As I get

1:45:15to the distal side, radial styloid

1:45:18process and ner notch. So this completes

1:45:21as we get down to the arm. You can

1:45:23review the video on hands and feet once

1:45:26we get past the ulna and radius. We're

1:45:28covering the rest of the appendicular

1:45:31skeletal system. So, we'll work through

1:45:32the coxal bone and down to the lower

1:45:34leg. We'll stop before we get to the

1:45:36feet because I did a previous video on

1:45:38hands and feet together. So, let's start

1:45:41with the coxal bone. The coxal bone or

1:45:43hipbone is a collection of three bones.

1:45:46So, I'm going to divide it into three

1:45:48bones from my green pipe cleaner up.

1:45:52This is all the iliam. So ilium. And

1:45:56then as I go to the posterior side, what

1:45:59I sit on from here over this is the is

1:46:03it. And I have a little piece of tape

1:46:05there to designate where the isium ends.

1:46:08All of this is coming over to become the

1:46:10isium. The anterior part that comes down

1:46:13to my pubic bone or the inguinal area,

1:46:16this is the pubis. So pubis, isium

1:46:21ilium. So, we're covering three bones

1:46:23and the landmarks of those three bones.

1:46:25To determine right or left, I just use

1:46:27that the medial side of the ilium is

1:46:30going to come to my ear and the pubic

1:46:32bone is how I talk. So, I put this

1:46:34nicely up like I'm talking with it. Hey

1:46:35Brad, how you doing? Versus when I do it

1:46:38this way, I can't connect it and then

1:46:40this sticks out awkwardly. So, this is a

1:46:43right coxal bone. So, as we learn this,

1:46:45right illium, right pubis, right issue.

1:46:49So, let's start with the illiam. and

1:46:51first identify just some of our

1:46:53projections that we see on the anterior

1:46:56side and then the posterior side. So

1:46:59we're learning spines. So directionally

1:47:02these two are called anterior superior

1:47:08iliac spine anterior inferior iliac

1:47:13spine. anterior superior anterior

1:47:18inferior iliac spine. On the posterior

1:47:22side, these two projections

1:47:25posterior superior iliac spine,

1:47:29posterior inferior iliac spine. So,

1:47:32you're using your directions

1:47:35and posterior posterior superior

1:47:38posterior inferior iliac spine. as I

1:47:41come over the top and it's rough but

1:47:44it's sharp on top relative to other

1:47:46landmarks. Not going to cut me but it is

1:47:48sharp. And this is a crest. On top is

1:47:52iliac crest. Iliac crest. When I go

1:47:56medial this is called the iliac fossa.

1:47:59Remember we're learning this for a

1:48:00reason. We'll put muscles and attach

1:48:02ligaments and tendons here. But the

1:48:04iliacis would fit here. So where I can

1:48:06hear with this is on the medial side and

1:48:10this is the iliac fossa. So iliac fossa

1:48:14iliac crest

1:48:16as they stay medial. We did iliac fossa

1:48:20and then we take this whole area and

1:48:21divide it into two halves. The top half

1:48:24is the iliac tuberosity.

1:48:28This whole rough area iliac tuberosity.

1:48:31The bottom half is called the uricular

1:48:34surface. and we're attaching the sacrum

1:48:36there. So on the posterior side staying

1:48:39medial iliac tuberosity uricular surface

1:48:44as I go underneath that this projection

1:48:47on the posterior side is called the

1:48:49greater sciatic notch. Greater sciatic

1:48:52notch. So we have the illium. As I go

1:48:56posterior to the isium this is the isial

1:49:00tuberosity. So this whole region here is

1:49:04tuberosity and this is what I sit on is

1:49:08tuberosity. As I come up I have isial

1:49:11spine. Isial spine. We did greater

1:49:15sciatic notch for the ilium but now we

1:49:17can do lesser sciatic notch of the

1:49:20isium. In between the notches I have a

1:49:23spine. Greater sciatic notch lesser

1:49:26sciatic notch and isial spine. We have

1:49:31issial tuberosity as it curves and

1:49:34elongates until I get to my blue tape

1:49:37here. This is the ramis. Isial ramis is

1:49:41spine issial tuberosity. When it curves

1:49:44and elongates, issial ramis.

1:49:49When I move over to the pubis, the

1:49:51pubis, it really just has two angles to

1:49:54it. I come down and then over. This is

1:49:56the superior pubic ramis. inferior pubic

1:50:00ramis. So I just determined like this is

1:50:02like a C here but it's backwards. The

1:50:05top superior ramis. So superior pubic

1:50:08ramis inferior pubic ramis. So just

1:50:11those two pieces on top I have a tubacle

1:50:15the pubic tubacle. Pubic tubacle then I

1:50:18have my ramis and my ramis on either

1:50:22side. Couple other things to look at is

1:50:24the hole is called the opterator

1:50:27frammans. Remember frammanas are holes

1:50:30opterator framman we get the nervous

1:50:32system we'll talk about the opterator

1:50:33nerve that comes down impacts and

1:50:35interervates on our adductor magnus

1:50:37muscles opterator framman's the hole and

1:50:40then where I connect the femur this is

1:50:45all the acutabulum

1:50:47acutabulum

1:50:49and the projection inside is called the

1:50:52acutabular fossa this top region of it

1:50:56is the lateral surface of the

1:50:58acutabulum. So it depends on how you're

1:51:00learning it. A lot of text they just

1:51:03cover the whole thing is acutabulum.

1:51:06The fossa is the depression inside. I

1:51:08have the lateral surface on top and then

1:51:12I have the notch acutabular notch here.

1:51:16So this is referring to illiam pubis

1:51:19isium. As we connect the femur, the

1:51:23largest and longest bone in the body,

1:51:26we're using the head of the femur to go

1:51:29into the acutabulum or the acetabular

1:51:32fossa right at the lateral surface. So

1:51:35the head of the femur within the head I

1:51:38have this little hole or divot here.

1:51:40This is called the phobia or the phobia

1:51:43capitus. So on the head I have this

1:51:46depression phobia or phobia capitus.

1:51:50We're use that to attach a ligament head

1:51:54and it makes sense that then I have a

1:51:56neck. So just like my body it truly

1:51:58represents more of a head and then a

1:52:00neck. So around it. So as we turn it and

1:52:04look at the head now you can see more of

1:52:08the neck. So that's the neck. As I stay

1:52:11posterior, I can see these larger

1:52:13projections called a greater troanter

1:52:17and a lesser troanter. Greater troanter

1:52:23and lesser troanter. And I see this more

1:52:26on the posterior side. And then what it

1:52:29creates is inner troanteric crest. In

1:52:33between the two troancers I have this

1:52:36ridge called the inner troanteric crest.

1:52:41Inner troanteric

1:52:44crest. On the opposite side the anterior

1:52:47they call it a line in between the two

1:52:48troanters. I have inter trocanteric

1:52:52line. So a line in between the troanters

1:52:55on the anterior side a crest in between

1:52:58my greater and lesser troanter on the

1:53:01posterior side. That's a lot. As they

1:53:04come down the posterior side along the

1:53:06shaft, this line is called the linear

1:53:10espera running down the entire shaft.

1:53:13Lineia espera. Linear meaning line.

1:53:15Esper meaning rough. It's a rough line.

1:53:18We use that for muscle attachment.

1:53:20Lineia espera. As I come down to the

1:53:23further distal side, staying anterior,

1:53:26this smooth section is the patellar

1:53:28surface to attach my sesimoid bone, my

1:53:30patella. So, patellar surface and then

1:53:33when I twist it and I look, I have these

1:53:36big notches here that are called

1:53:38condiles. Condiles. Now, you need to

1:53:40know medial versus lateral. How do I

1:53:43know which size my medial? My head has

1:53:45to go in to my acutabula. So, this has

1:53:50to be on the medial side. And it's

1:53:52really no matter where I put it. So if I

1:53:54follow this is medial all the way down.

1:53:58This is the medial condile. So medial

1:54:02condile, lateral condile.

1:54:05Turn it this way. Doesn't matter. And

1:54:07look for the head. Medial condile,

1:54:10lateral condile. In between that I've

1:54:12got a space. We're use that for

1:54:14ligaments for the knee. Interular

1:54:17fossa. So intercondular

1:54:20fossa is the space in between my two

1:54:23condiles. How do I do right or left with

1:54:25this? Remember I said this is medial and

1:54:28I use all of this to be posterior. My

1:54:31troanters and my lineosphere have to be

1:54:34posterior. So if I stay posterior I need

1:54:37this to go into my body. So this is a

1:54:39right femur. So at the head the neck my

1:54:43greater trocanter lesser troanter. As I

1:54:46come down the shaft linear spa to my two

1:54:50condiles,

1:54:51medial condile, lateral condile,

1:54:54intercondular

1:54:55fossa. My two condis

1:54:59of the femur connect to my next largest

1:55:02bone of the tibia. So condiles match

1:55:05with the condiles.

1:55:08I have this condile and this condile. So

1:55:11these big round projections for my two

1:55:14condis to match with my two condiles.

1:55:16How do I know lateral versus medial? As

1:55:19I come down to the distal end, this

1:55:22projection is called the medial

1:55:25malololis. So we often say when we feel

1:55:28like the balls on our foot as we get

1:55:30close to our ankle, you're feeling that

1:55:32round projection on the medial side.

1:55:34This is the medial malololis.

1:55:38Medial malololis. So if this is medial

1:55:40malololis and I come all the way up,

1:55:43this is medial condile. So this is

1:55:46lateral condile. Medial condile, lateral

1:55:50condile. In between it,

1:55:53I have a couple tubricals. They're

1:55:56called lateral and medial tubrical. This

1:55:58is still medial.

1:56:01the two projections medial tubrical

1:56:04lateral tubrical but it's the tubacles

1:56:07of the intercondular

1:56:09eminence. So this landmark is called the

1:56:13intercondular eminence in between my two

1:56:15condiles intercondular eminence and it's

1:56:18created by the two tubacles medial

1:56:20tubrical and lateral tubacle as I come

1:56:24anterior

1:56:26to help connect the tendon. This is the

1:56:29tibial tuberosity. Tibial tuberosity. So

1:56:33my condiles tibial tuberosity. As I come

1:56:37down the shaft, it projects and has a

1:56:40crest to it. And it's called the

1:56:43anterior margin. So when you say you hit

1:56:45your shin or kicked your shin,

1:56:48this is the anterior margin of what

1:56:50you're actually hitting. So anterior

1:56:53margin. Sometimes you see anterior

1:56:55crest. And then like I said when they

1:56:57come down that most distal portion

1:57:00medial malololis. So that's the tibia.

1:57:04And now I'm gonna connect

1:57:08my fibula next to it. Before I do that,

1:57:11right or left? We said this is the

1:57:13medial malolola. So this has to stay