- Lesson Details
Expert animal draftsman and painter, Joe Weatherly, breaks down the complex subject of animal anatomy using clear and easy to understand concepts. In this video lesson, Joe analyzes the hind limb of a horse and a canine. Joe also diagrams the muscles of a dog, and teaches you the terminology and importance of each muscle.
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Joe Weatherly breaks down the complex subject of animal
anatomy using clear and easy to understand concepts. You will
learn how to tackle a wide range of animal types and you
will gain a methodology for quickly drawing any new animal
with confidence and force.
In this video lesson, Joe analyzes the hind limb of a
horse and a canine. Joe also diagrams the muscles of a dog
and teaches you the terminology and importance of each muscle.
and do two views: side view and back view and then on a
different diagram, different film we can look at a
carnivore, but the first
diagram is going to be more or less the key muscle shapes with
a few specifics and then I'll try to break down a few more of
those on a more specific level from behind. Okay. So anyways
you see I'm covering the top of the the iliac crest here, almost
the entire pelvis. This is the gluteus medius. Now, I know on
the human the gluteus medius is small or smaller than the
maximus but on the horse, it's a big muscle. Okay, the origin
of the gluteus medius is the surface of the depression in a
across the longissimus muscle which we don't really see here.
And also the upper surface of the ilium of the pelvis.
So it sort of wraps over the top of the pelvis and goes
forward into the top of the longissimus which
is basically the loins.
Okay. The insertion point is the top and back of the end of
right around the great trochanter area. And the action
is going to be extending the hip joint. So very important
muscle for propulsion, holds a limb away from the body as
So very large muscle becoming thin in the front, which we
don't really see too much but then
because very thick, very massive, gives the buttocks the rounded
form that we see on the top of a horse's hind quarters there.
The rear edge is going to get covered by the gluteus
superficialis and also the biceps femoris, but for now,
this is where the origin and the insertion point is on this
Okay coming along the side of the thigh here,
we're going to deal with that group of muscles called the
quadriceps, otherwise known as the quadriceps femoris. What's
included in this group is the vastus lateralis, the vastus
medialis, intermedius, and the rectus femoris. Okay, so
hopefully you know some of those from the human leg,
they're the same although they look a little different here.
So this is going to be like the
flexor and extensor demonstration that we've done
forearms and things in the arms. Okay, instead of going
into individual quadricep muscles here, I want to see
this area as a mass and to tell you the truth that's what you
see when you're looking at a horse because it's covered with
other things. It's not as obvious as the hamstrings are,
more or less you can consider these deep muscles.
But anyways, most of that is originating on the original originating on the
outside surface of the femur and insertion - all the parts are
the entire front surface and upper edge of the patella. So
those are all - you see I've drawn those to go over the
So you got to look at a diagram in a book. It's a little
complex, but there's -
from them going into the patella like that, that actually
takes them into ligaments that brings them into the upper end of the
tibia, the tibial tuberosity, so
think about the quadriceps on a human, how the rectus
femoris goes into a large tendon, goes over the knee cap
like a strap and attaches to a tuberosity on - a little bump on
the front edge, front upper edge of the tibia. Same thing going
Next up on the list here a very thin triangular shaped muscle.
This is called the tensor fascia latae and it's
originating from the point of the hip so that just below the
iliac crest there and the outer corner of the ilium and then it
inserts into the fascia of the leg that surrounds it. Now it
doesn't do so on a dog, but
on a dog it stops up at the top, but there's going to be - you
notice how I've taken this blue line all the way down past the
patella because it's inserting
via a fascia surrounds the vastus lateralis and the rectus
femoris and cruising on down to the front edge of the tibia. So
just think starts at the top - or excuse me out of the bottom of
the iliac crest,
creates this triangular depression and then goes all the way down
into the very top edge of the tibia passing through the
Okay, there's a lot of - that's a lot of information, but that's
anatomy for you.
Okay, again muscle is very triangular and it actually
forms the edge of the upper end of the thigh. There's going to be a
muscle in front of that but this is mostly what the edge
The belly or the bulk of it begins on the point of the hip
and cruises down past the patella.
You know, here's a muscle that is actually
not that noticeable on a horse, but it's still there. This is
actually more noticeable in the dog and the feline. This is the
sartorius, which the longest muscle in the human body.
Sartorius, fairly minor muscle, not very visible on the surface
of a horse, but it originates deep on the fascia and the
tendon in the region
where the upper end of the thigh meets.
Comes very tendinous near the knee. So again coming from the
top or excuse me the bottom of the iliac crest and working its
Eventually ends up on the
tibia, but we don't see that because it's going behind
the kneecap right now.
Okay, marking the gluteus here.
And the group of the quadriceps, the key muscle shape there for
the quadricep group.
So to fill up some of the sacral area on the top of the
hind quarters here
is a massive set of muscles
called the biceps femoris.
In other words the hamstrings.
So you see how on a horse anyway, it stops it starts very
much at the top and wraps around the back of the ischium
and comes down to the tibia.
So a lot of information in this muscle, but just think about it
the structure of this muscle is very massive muscle that
consists of the long head and that's the head - that's the
main mass that is behind the orange gluteus muscle there.
That's otherwise known as a long vastus, nowadays most books
group that up and call it the long head of the biceps
And the short head, this separates into two portions
for a total of three forms, which I'll darken in.
Okay from the profile, this is the last muscle you're going to
on the horse.
It's called the semi tendinosis and from a straight-on side
view that is the profile of the animal. It's not the biceps
femoris. It's actually the semi tendinosis which originates in
the first and second tail vertebrae, fascia of the tail, and
the lower edge of the rear end of the pelvis. So up there near
where the tailbone's coming out and inserts fascia of the
inside of the leg ultimately into the front of the tibia.
Which we don't see because it's going behind it.
And it also has a little tendon that comes out and goes on to the comes out and goes on to
the heel bone.
Long muscle starts at the -just thing about it this way: it starts
at the top of the base of the tail, passes down back of the
thigh, and ends up on the tibia.
Its main action is extending the hip joint and the ankle
joint, flexing the knee joint, rotating the leg inward.
What I'm coloring in here is
the edge of - or the fascia area
of the biceps femoris, so this is - muscle stops,
hits this sheath, which I'm going to cover up with a
that goes on to the lower leg, but I just wanted to show that.
Okay, think flexors and extensors again here, think
front and back.
This is an extensor muscle. This is the main - well, this is
actually the main large muscle in that area on a horse anyways,
but this muscle is going to represent a few others as well
on the side of it. But this is the extensor digitorum longus,
otherwise known as the extensor pedia. And it originates from a
depression on the outer surface of the very bottom of the
Insertion is upper edge of the front surface of all three
bones of the toes. So it goes all the way down and goes over
three joints in the hoof. Now behind it here is the large
mass of the back of the leg,
Very thick sort of club shaped muscle that forms a bulge or it
forms the bulge of the calf and what it does is terminates into
a very tendon - a very top tendon that locks onto the calcaneus
there, the heel bone. So that is actually called the Achilles
tendon. I'm sure you've heard of that one. So you have this
very large muscle that has a lateral head and it also has
medial head and then it goes down into a big tendon and locks
onto the calcaneus.
The outer head's
starting on the
rear edge of the femur. So it goes way up into the femur
there. We can't see it because the biceps are in the
The action of this muscle is flexing the knee joint.
Ankle joint. Helping to propel the animal forward.
Okay, I'm going to pull one of the other legs out now so we
can get a
view of the inside mass here.
The inner thigh, that's one of the areas that a lot of times
people - beginners - don't like to skip when they're doing the
But it's not that bad. We're just going to take a look at
the top portion here of thigh and what is on the inside. It's
you know, the abductor muscles really is the main theme Here.
Okay, so I've laid in my bones.
Femur to tib-fib to calcaneus.
Tarsus to metatarsal, phalanges.
All right, the thigh group that I'm dealing with here is two
muscles, one is the semimembranosus and the other one is gnosis. And the other one is
the gracilis. Take a second look at those
in the back view so we can see where they come from
But the semimembranosus -
well, actually let's start with the gracilis. That one
there's a calf shape coming in right here with the
The gracilis comes up from the
the bottom of the pelvis and works its way down into the
All right, I guess I'm just refining those two muscles
again. That's the semimembranosus and the
comes up from the
sub scapular ligament, passing from the second tail vertebrae
to the top of the rear end of the pelvis, and inserting into
the inner surface of the lower end of the femur.
All right. We already talked about the calves. That's the main
mass there of the gastrocnemius and it's tendon, which the Achilles
tendon locking onto the heel bone.
Okay adding the suspensory ligament to the back of the
And a little bit of that extensor shape to round off the
front of the lower leg in blue right there.
the hindquarters of the horse. This is - so most of these
muscles we've drawn out right now. We're just taking and
looking at it from the back. So this is the gluteus medius
coming up from the
top of the pelvis there.
Working its way over to the side
and inserting on the upper end of the back of the femur.
So it's like taking that shape that we have from the side here
and visualizing it from the back.
From the top to the bottom.
Okay, I'm letting some of the landmark show through there
just for the sake of the diagram.
And I'll come over here on this side and just sort of draw but
I won't do any muscles on the right.
Just draw the form.
See, I'm finding the center and kind of splitting that. They it kind of splitting that they
have one one hamstring mass on each side.
And I made that little circle there, that's going to be the
tip of the calcaneus. So the heel bone, the shorthand heel
Okay long vastus, otherwise known as the entire group is
known as the biceps femoris.
Just the long vastus is the long head of that muscle.
Okay now next up on the list.
The muscle that's seen from the - in direct profile. This is the
semitendinosis. It's the orange muscle on the side view
remember long - it's a long muscle. Starts at the top of the
base of the tail,
passing down and ending up on the tibia.
Goes right next to the ischium there, too.
Okay continue with the other section, the other two heads of the
biceps femoris. These will be here in pink. This is the
short head which has two sections to it.
It's all tucked away with the short head was originating in
lower part of the end of the pelvis. Okay hamstrings from
the back, look at how the
pink parts here of the biceps femoris against the semi
Sort of grab onto the calf like tongs - like salad tongs or
something like that. So you can - whatever you got to do is
visualize this stuff. They are sort of - I see it as sort of
grabbing onto the gastrocnemius there.
Okay inside muscle here, this is the gracilis.
Inside of the thigh now.
Okay gracilis is coming up from the
very bottom of the pelvis.
Midline of the bottom of the pelvis. It inserts on the
medial patellar ligament and the inner surface of the tibia,
which is not really being seen from the back view, but that's
It's a muscle that pulls a limb towards the center.
Center of the body. And extends the hip joint.
So wide thin rectangular muscle.
And filling in the gap here, we have the semimembranosus.
Easier to see from the back.
Well almost impossible to see from the side, but
it fills in that space right there. That was the missing
Okay, it originates from a
So up there near the sacrum there's a ligament. This muscle
is originating from that and coming down and inserting
on the inner surface of the lower end of the femur.
Muscle extends the hip join,t pulls the limb towards the
center of the body.
Okay, marking some landmarks there. That's the ischium.
That's a landmark. That's why I gave it the white X. I'm sort
of outlining a little bit more of the pelvis.
So you start to see how that is the top of the box that we use
The corners of the form are right there where it starts
with taking turn down.
Gastrocnemius mass right here.
Originates on the back of the femur, comes all the way down,
inserts on the heel bone.
Okay, there's the tendon that I'm talking about that
terminates on the calcaneus.
There's the calcaneus, the round circle that's representing the
tip of that bone.
Peeping through to the side there the peroneus muscle and on the
inside the perforatus muscle. So a couple more leg
muscles there that kind of people out. Soleus was peeping
out a little bit, too.
And that creates the outside back contour of the horse.
What do all these lumps and bumps mean? That's what you got
to ask yourself when you see, you know, the live model in
front of you.
Alright there's the line for the suspensory ligament.
So now I'm just drawing and what I'm doing just drawing and what I'm doing
is showing the contour of how these bones come together right
here in the back of the leg.
What all that bulk means right there.
Get my ellipse in when I'm drawing the back of the hoof
This is a straight on back view so we don't see much of you. So we don't see much of
anything else. Very elliptical.
Draw through like it's made of glass.
Okay we'll wrap things up here with a little bit of skeletal
lay in, I guess you could say. So keeping one side muscular, one
side skeletal. And so we can really see how the skeleton of
the hind limb takes and works its way into that area.
Okay this area here. You got to think about like this: if we
draw a box here and zone in on this area, what's really
happening? It's bone against bone. So we're seeing one, two,
three, four corners there. The corners of tibia hitting the
metatarsal bone and the circle in the middle is the calcaneus.
Same thing with a knee. If you look at a knee from the front,
you put a box around it and say what do you want to know about
you know, you want to know about the corners, you want to
know what's in the middle it. Was there a ligament there? So these are
the things that you can do to make the joints come
alive and look very anatomical and on the living model.
Great trochanter faces outward.
Touches the surface almost.
Slightly foreshortened and what's important here is the
volumetric mass of that bone.
Know it's there, but also know what it's volume is.
Easiest way to do that is to draw ellipses around it.
Okay tibia and calcaneus.
You got to do these bones over and over again so you have them down
carnivore we're dealing with now instead of the herbivore
and this is the canine so the back section of the dog. Okay
starting up on the pelvis
right behind the iliac crest there is the gluteus medius.
It's the most bulky of the two, again just behind the crest of
the insertion point is the
top back of the end of the femur, upper end of the femur.
Okay, thick fleshy belly on this muscle.
And it started ends into, it comes very tendinous as it
comes down and tapers
and its edge hits the inserting part of the femur right there.
Okay muscle behind it is covering the back edge of the
gluteus medius and this is called the gluteus superficialis
And while I'm at it I'm going to lay in the triangular shaped
tensor fascia latae.
Okay, origin of that muscle is the lower edge of the front of
And the surface just under the gluteus medius.
Okay. Now I'm going to put some - take some black here and define
some of these shapes again. So starting with the gluteus
Into the gluteus superficialis list
thin v-shaped muscle converging with the femur.
And the front portion actually kind of comes up against the
Rear portion is going to be covered with the biceps femoris
when we get to that.
Alright, so anyways back down here to the tensor fascia.
Again origin under the edge of the front of the pelvis
and this under the surface of the gluteus medius.
It inserts into a fascia covering the thigh muscles.
So think of it as having two sections, it has the muscular
part, the triangular area I'm drawing right now. And then
the lower edge is directed downward and forward from the
upper end of the femur and that is going to be the fascia latae
part of the tensor fascia.
Further that's the sartorius, very long narrow muscle.
Origin is the front portion of the - front portion may -remember
there's two muscles here. Well one muscle's got two parts, but
from a side view we only see one.
that front portion is on the line of the edge of the front
of the pelvis. Rear portion that's on the inside of the
pelvis, front edge.
Coming all the way down
for continuous insertion
on to the edge of the tibia there. Kind of goes inside the
behind the kneecap as it were.
See so the sartorius beginning on the front end of the pelvis,
ending on the inside of the knee. That's a good way to
think of it. It's kind of holding in all those quadriceps
that are behind it.
All right. I'm cutting in really bold here with the large
mass of the biceps femoris and notice how we have the - stepping
from the gluteus superficialis, tail sticks out above that list tail sticks out above that
and then it kind of steps down. Well, it's really, you know,
it's the sacrum going down and onto the
bottom part of the pelvis, which is the ischium and then we
have the - this is sort of like, you know, wrapped over really
tightly. We have the biceps femoris, otherwise known as the
So this is one of those crazy muscles I talked about in the
horse. It has different insertion points, different
parts of it.
On the horse. We see three distinct sections of this
muscle, but on the dog it'ss really just two.
Anyways, it's fanning out as it gets towards the lower leg.
So the origin point for the superficial head is the outer
corner of the ischiatic tuberosity at the rear end of tuberosity at the rear end of
the pelvis and also the rear third of the sacrotuberal
Deep in which we don't see is the bottom of the outer corner of
the ischial tuberosity deep into the origin of the
So yes, you need anatomy book to break that down what I just
said but then again, you know, the more times you go over it
and see it for yourself, draw diagram for yourself, label it
for yourself, that's when I start to makes a lot of sense
All right. So as you can see it's inserting into the fascia of
the leg. That's the part that I left blank right there in front
of the sartorius. And ultimately into the patella.
The patellar ligament and the front end of the upper part of
Then not to confuse things there's a little part that
kicks out and goes - a little tendon that kicks out and goes
all the way down into the calcaneus.
Okay, so I'll give that fascia a little bit of color.
Underneath that fascia, underneath
all that -
the sheath right there is the quadricep group, quadriceps
femoris, which includes the vastus lateralis, medialis, and
intermedius, and also the rectus femoris. So I'm drawing it now
as a key muscle shape.
Again, think about the quadriceps on the front of your
thigh. The hamstrings behind your thigh. So what I'm
interested in now is the bulge of this muscle underneath
that sheet there from the tensor fascia. Okay. So
there's some directional - directional stroke there to
sort of show the roundness of it.
This is the semitendinosus.
And this muscle is originating
on the outer corner of the rear end of the pelvis.
Insertion point is the front edge of the tibia. So it's
going all the way down into the
tibia about a fourth of the way down and also the heel bone.
All right, calves. Going for the bulk of the - bulk back of
the lower leg
with the very strong,
thick, club-like shaped gastrocnemius.
And this is a really important muscle
for the back shape of the leg and as it goes into the tendon
it's really important too - the Achilles tendon - because
underneath that tendon is always a space
with a thin membrane going over and that's a good place to get
some tone or a good place to get a line if you're
drawing with a pen to show that. You can pinch that area right
there, it's very thin. But the tendon is very taut.
Okay, so working the lateral head now of the gastrocnemius
it is originating on the very bottom of the femur.
Going over the tibia and the fibula.
Okay. So let's go to the smoother shape that's below the
crest of the tibia. This is the tibialis cranialis muscle,
otherwise known as the tibialis anticus and in humans it's
referred to as the tibialis anterior.
Okay the origin on the dog is a vertical line
on the outer side of the tibia.
Just to the outside of the front edge and continuing up
into a concave area on the top outside of the bone itself.
Coming all the way down to an insertion point on the foot and
into the lower tarsal bone.
Like I said, a lot of these flexors and extensors they're very
fleshy and round up at the top and then they terminate in the
tendons that go all the way down into the phalanges.
Same thing with the four legs.
Okay, so wider at the top end
and develops into a flat tendon at the lower end.
Alright then next to the tibialis we have the extensor
digitorum longus muscle, otherwise known as the extensor
Another muscle that's structurally
very fleshy up at the top and then terminates into a tendon.
So the origin is from a depression on the outer surface
of the very bottom of the femur. So this one is actually
touching this the very edge of the femur
and the insertion point is going to be the last toe bone
of all four digits,
which I've done in a very general way down there.
So a lot of these muscles in the legs varied a little bit on
some animals, like sometimes on animals these are covered but
they're still there. We just don't see them as much and on
other animals they are more exposed.
So just depends usually, all the animals have them it's a matter
of what shows through on the superficial level.
Okay, this little green one right here I'm doing, this is
called flexor digitorum profundus. Otherwise known as
When I say otherwise known as that means that some of the
older anatomy books like to call it that and then things
have changed over time and some of the newer books
call it what I say in the first place
usually. Depends on the book you're looking at. Okay, this
one, origin is
right about middle third area surface area of the tibia.
Continuing upward on the outer side of the rear surface
of the upper end of the tibia, the adjacent area on the
A lot of places.
And the ligaments between these bones inserting on the dog,
bottom of the last toe, going all the way down and on the
bottom of the last bone of the fore toe I should say, the fort. Oh, I should say four
That was a mouthful. So this one is - again these muscles get
very intricate as they get down towards the toes for drawing
purposes. If you can just have this line going down there, you
know, it's going towards the direction at the paws you're
Okay, so I want to come in now and show the kneecap right
there. Make sure we know the where the patella is, remember
that sticks out and then the crest of the tibia is below the -
that's the next bump. There's two things to look for there: the
tubercle on the tibia and the crest of the tibia and
then you get this, that's very angular, then you get
the rounded ,elongated, swooping line of the - that the
So that's when it comes - that's when it comes in handy for
drawings. Like what do these muscles do to a profile?
Okay, so I want to draw a little bit of the - little more dog here
just to make it connect, so to speak. There's some loin area
here, some rib cage,
Okay. Remember that loins, always say it, very round right,
All right. So thicken up that tail, give it a little rhythm.
Stepping down right there.
And there you have the muscular hind limb area of the
dog, going over the surface form there with a dark line to show
the contours of the form.
And little adjustment there in the hamstrings. So you can take
a look at this and see how it's very similar but yet a little
bit different than the hind quarters of the
equine form that we compared earlier.
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1. Lesson Overview45sNow playing...
Watch the whole lesson with a subscription
2. Hind Limbs of Horse15m 41s
3. Hind Limbs of Horse Continued12m 34s
4. Hind limb of a Canine16m 21s