Anatomy & Physiology Appendicular Skeleton

Hi and welcome back to www.educator.com.0000

This is the appendicular skeleton.0002

It is named after the appendages that will be the arms and legs and the bones associated with the movement and stability of those.0004

Let us start with the pectoral girdle.0013

The pectoral muscles are up here, this is girdle is attached to that region and helps give your arms movement and stability.0015

We are going to start with the clavicles which are also known as the collar bones are here and there are 2 ends.0024

At one end they are attached to the sternum.0033

They call it the sternal end of the clavicle that is the more medial side.0038

The other end is the acromial end.0042

It is called that because of a part of the scapulae which we will get into in a second.0045

You have 2 separates clavicles or collar bones.0049

That is part of the stability of not just the upper arm bones but also of the upper chest.0052

It connects directly to the sternum which connects to the rib cage.0060

The scapulae that is a plural term also known as the shoulder blades.0065

This is the frontal or anterior view as if we are looking through this person’s chest.0071

From the back the shoulder blades are more obvious and they have a lot to do with connecting back muscles associated with movement of shoulder.0080

The scapula is interesting because most of it is this giant blade looking thing that they call body of the scapula.0092

These little projections up here that connects with the clavicles are important.0099

This right here is called the acromion.0103

You can barely feel it if you find where your clavicles end, this bump right here is the acromion.0106

Some people call it the acromion process.0117

That is why they call this the acromial end.0119

That is much the pectoral girdle.0124

Another thing I want to mention is that in the next set of lesson in joints we will talk about ball and socket joints.0127

The classic ball and socket joint is a femur connects to the pelvic area.0133

You could claim that this is ball and socket joint.0137

It is the same basic type of movement but it is not a hollow bony section that is fitting the head of the humerus or the upper arm bone.0140

It is a rotator cuff and it is not bony but it is a lot of connective tissue, ligaments, tendons, and muscle fiber associated with fitting in that part of your arm.0151

To the upper appendages which is the arms, if we start with the most proximal or closer to the torso that would be the humerus.0168

The way that I remember that this is the humerus is people refer to as hitting your funny bone.0179

Humerus is spelled differently but you can help remember it from this little trick.0186

By the way, the funny bone we are not referring unlike your knee cap which is a separate bone in your leg, there is no free floating elbow bone.0195

The elbow point is a part of the ulna that we will get into in a second.0208

When you hit your funny bone, it is when your arm is in a position and you hit just right, there is nerve that is not too deep under the surface of the skin0211

and if you hit it you are getting the stinging feeling that we all felt before when you hit your funny bone.0222

This will be the head of the humerus which fit into the rotator cuff.0228

Down here are notches that fit in the radius and ulna the 2 forearm bones.0233

The radius and ulna make up the part of the arm.0241

The way that I keep it straight is the ulna is on the pinky side.0246

The radius is on the thumb side.0266

You can see from this image that if this individual rotates the thumb medially or towards the middle of the body,0268

the radius crosses over the ulna and stays with the thumb.0277

On the right hand side of this picture, you can see that when the thumb is facing towards the outside of the body it stays with the thumb and the ulna is on the pinky side.0282

The carpals is the general term for wrist bones.0293

You could see from this diagram they label this one bone in the wrist as a carpus that is a general term you could use to describe each individual bone.0299

In general you can call all of these as carpals.0308

Later on in the joins chapter we will get into carpal tunnel syndrome and why it exists.0312

There are plenty of wrist and finger bones.0318

The amazing thing is if you add up all your wrist bones, bones of the palm and fingers and you add up all your ankle bones, and the bones of the feet,0322

the total number is more than 50% of all the bones in the body.0332

There are about 206 bones in a human body all the wrist, ankle, hand and foot is 106.0337

That is an interesting fact.0346

The metacarpal is the palm bones.0348

If you ever seen a skeleton display and say the fingers are long, the metacarpal bones you do not normally see very well in a person’s hand.0350

The metacarpus labeling is still one of them but the metacarpals are those palm bones.0360

The phalanges that is a general term for finger bones and the same term applies to the bones of the toes.0366

You can see name each of these phalanges something more specific and I will give you a hint there.0377

Thumb is 1, pointer finger 2, middle finger 3, ring finger is 4, and pinky is 5.0383

You can use those relative position terms we went over before distal and proximal to name them.0392

If you look at the thumb there are only 2 phalanges and it is shorter than the other ones.0398

All the other fingers has 3.0406

The one that is closest to the trunk of the body you can call that proximal phalanx 1.0409

The word phalanx means 1.0418

You do not say phalange, phalange is not a real word but phalanx is a singular word.0429

Proximal phalanx 1 and this one is distal phalanx 1.0437

That is the first digit.0443

There is a middle phalanx in all of these.0448

This would be distal phalanx 2, middle phalanx 2, proximal phalanx 2.0454

All the way to number 5, distal phalanx 5, middle phalanx 5, and proximal phalanx 5.0461

Moving on to the pelvic girdle.0468

Pelvic girdle also called as pelvis is made up of a bunch of bones fused together.0474

We can call the pelvis the coxae or coxal bones.0480

There are 3 main segments.0487

The illium is the classic part that we think when we imagine the pelvis.0489

The ischium is right down here.0495

The pubis is in the pubic region.0498

We will get into the pubic arch associated with that in a second.0503

The part that is most easy to feel on the pelvis is the iliac crest.0507

Since this is the illium and there is a corresponding illium on the other side.0515

Right there is known as the iliac crest.0519

There is more on this side of course.0524

When it comes to the pubis, each coxae made of illium and ischium is connected via what is labeled here 8 is a cartilaginous path called the inter-pubic fibro cartilage.0530

Similar to the parts that you would see within the vertebrae of the spine, you have a joint there that is not highly movable0548

and that is meant to connect those 2 coxae at that pubis region.0557

When you look at male and female pelvises, the general differences is that when you look at this angle right here between each pubis,0563

if it is 90 degrees or less it tend to be a male pelvis.0575

If it is 100 degrees or wider, it tends to be a female.0579

There are exceptions, in general female pelvises appear wider.0585

That corresponds to hips that are bit wider on an average female compared to men.0593

When it comes to giving birth, that wideness helps accommodate the baby coming out.0597

Finally, the lower appendage or the legs.0603

The femur is the largest bone in the body.0610

The head of the femur fits in very nicely to what is called the acetabulum of the coxae.0614

On the previous slide if you look back, there is a hollow region that is on the lower side, inferior lateral portion of each side of the pelvis.0625

It is a nice socket to the ball the head of the femur.0637

Down the lower end it connects to the knee section and you can see that the femur has this angle that coming medially as you go from top to bottom.0641

If you look at angles at other primates legs connect to the pelvis not quite the same and it has to do with our locomotion and a little bit of our posture.0654

If you compare the legs of a chimpanzee to a human it is very different in terms of angle, it connect to the pelvis and come down to the leg.0665

The patella is right here, the knee cap and in the joints chapter we will talk about the ligaments associated with connecting the patella to the tibia0674

and connecting the patella to the muscles within the quadriceps.0686

The tibia is the major sheen bone right here.0691

When you feel that sharp point in the middle of your sheen, you are feeling the tibia.0699

On the side if you look laterally that is the fibula.0711

If you press in on the side of your calf you can feel the fibula.0716

The way that I keep this term straight is0722

A nickname for a little lie is a fib.0725

I think fib little lie, fibula smaller or more little of the 2 sheen bones.0731

Tibia the big one, fibula the smaller on that is just lateral to it.0738

You got corresponding to the wrists and hands, instead of carpals we call them tarsals here.0745

The tarsals all of these bones in here, the back one is the heel or calceneous on the back0753

and that will comes up again because of the calceneal tendon also known as the Achilles’ tendon.0764

Achilles’ tendon connects to that heel bone and that is the calceneous, the largest of the tarsals.0774

The metatarsals correspond to the palm of the hand.0781

The metatarsals would be those bones that are inside the foot that you can feel but you cannot see easily.0786

All of these bones here these would be those metatarsals.0793

Finally, the phalanges.0800

Phalanges would be all of these bones in here.0802

We have the same naming system when we look at the fingers.0807

When you look at the middle toe for instance, you would have the distal 3rd phalynx, middle 3rd phalynx, and the proximal 3rd phalynx.0811

That is the legs and that finishes up the appendicular skeleton.0827

Thank you for using www.educator.com.0831