-: So we're gonna go into all the muscles
that are the most important that are involved
in dorsiflexion.
And over here, I've taken the liberty of drawing
all the muscles in in different colors.
So starting from medial,
we're gonna cover the anterior tibialis muscle
which sits right here.
It attaches to the tibia right here on the inside,
and another attachment that sits in between the tibia
and the fibula right in here.
And then on the foot side, it's going to run right across.
It's going to attach right into the cuboid bone
and also the medial portion
of the first metatarsal bone here.
Okay, then moving along to the side here.
We've also got the extensor hallucis longus,
which attaches into the anterior fibula.
So that's a little bit more lateral
than the anterior tibialis, okay.
Then moving along to the toe extensors
which also crosses this ankle joint.
It's going to run up to this
kind of tibial tubercle up here.
It's gonna run all the way down that fibula.
And that is called the extensor hallucis longus,
extensor digitorum longus, sorry.
Then we've also got, most lateral,
that's going to attach to the fibular surface,
right here in green.
That's going to be your peroneus tertius,
which comes right down
and attaches to the fifth metatarsal, the proximal tip here.
And that's also known as the fibularis tertius as well.
And that basically rounds out the most important guise
for dorsiflexion of the ankle.
Okay, so as far as this whole complex is concerned,
the whole ankle complex,
we have a variety of bones that provide a different variety
of different motions that can occur at the foot
and the ankle complex.
And it starts off with the talocrural joint
which is essentially the,
if you look at the medial and lateral malleolus
which are at the bottom of the tibia and the fibula,
which is right here, tibia, and this is the fibula.
This forms basically the bones of your ankle.
Right up underneath that is the talus
which sits right here in front,
and that takes care primarily
for the dorsiflexion/plantar flexion components.
This one doesn't quite move as well as, I think.
Some people have better motion than this.
But as we move forward, if you could turn to the left side.
We also have our calcaneus bone,
which is this big bone that makes up the heel.
And that guy makes up pretty much about 3/4
of the entire ankle here.
But that one is primarily responsible for allowing
for this pronation/supination motion that occurs, okay.
Now, just because it does pronation and supination
doesn't mean that it's exclusively that.
It is going to add a little bit
to the amount of dorsiflexion and plantar flexion
that we can get.
And we'll see that these motions occur together, okay.
As we move forward,
more interior into this like foot complex,
we've got this collection of three or four bones here,
and these are the cuneiforms.
And we've got a little bone here called the navicular.
And then this forms what's called the midtarsal joint
which has functions that actually add to dorsiflexion
and also plantar flexion from the forefoot.
And you also have kind of a longitudinal axis
so it allows for this kind of motion as well in the foot.
We might go a little bit further into that
as we kind of look a little bit closer onto Chelsea's foot
and how that actually moves in real life.
And then as we're moving out here, we've got the metatarsals
and then out to the phalanges of the toes.
So that makes up the primary structure of the foot
as a whole.
And we'll start going over more in detail
what the motions are
and how that actually affects us when we're moving.
Okay, so dorsiflexion as a whole.
As the person moves their ankle through dorsiflexion,
it's not just purely this sagittal plane
up and down motion.
All right, so if you notice,
all these muscles are biased
towards the lateral side of the leg.
So as this ankle starts moving up into a dorsiflex position,
it's not just gonna stop right here.
It's actually going to continue to deviate
into pronation in order to pick up more range, okay.
Now, so this might be a reason why, in some cases,
if you start, if you have actually limited dorsiflexion,
you're gonna see a lot of people's feet
kind of overly pronate as they start doing a lot
of their movements, okay.
But this also is important for when we're trying
to train this muscle.
Because these muscles all kind of pull towards pronation.
So if we're actually doing motions
that start training these muscles,
we're also gonna have to have some conscious intent
to wanna pull them slightly laterally
in order to get a maximal contraction
through these guys here and not just straight up.
So one thing I wanna make sure to mention
is that anybody who knows a little bit about anatomy
will know very well what the function
of the anterior tibialis is,
which is this medial muscle right here.
And that is commonly known as like
the primary dorsiflexor of the foot.
But if you actually think about it,
because this has a shorter attachment here
and it moves to right to attaching
at the metatarsal right there,
it actually doesn't have as long of a moment arm as,
say, something like this one does.
Which this one is the extensor digitorum longus
which actually runs all the way up here,
crosses all of these joints here,
and then also crosses all the joints
out into the tips of the phalanges.
And so, because that's the case,
this one has a very important stabilizing role.
Because as it actually shortens,
what it can do is cinch up a lot of the bones here
that you can see here on this skeleton.
And what it does is it adds a tremendous amount of stability
through all of these joints here
which stabilizes the forefoot
which helps to make it kind of more of a rigid plank
that then allows the rest of these muscles
to do their job a lot better.
So we actually have quite a few more intrinsic stabilizers
of the foot, which we won't go too deeply into right now.
But just know that as the primary dorsiflexor of this foot,
this one, because it has such long mechanics
and also has the ability to increase stability
through that forefoot,
it's gonna be able to produce a much cleaner and a much...
It's gonna be much more advantaged
to actually move this foot
into its full range of dorsiflexion.
Because the more stability that we can generate,
the more mobility there's going to be through the joints.
So that's an important distinction here.
Kind of an extension of this explanation,
and we're talking about the dorsiflexion
of the ankle as a whole and this extensor digitorum longus
basically extending all the way out to the phalanges.
When it comes time to train dorsiflexion,
it actually might be more advantageous
to put the loading kind of further out
towards the ball of the foot.
Just because that's going to include a larger percentage
of these tissues that actually train the muscles
to create stability through the entire forefoot
which is gonna be much more beneficial
than what we see typically,
which is an anterior tib raise
which essentially is being loaded right close to the ankle.
Because the thought is, if we're here,
we're gonna train this muscle more directly.
But what I've seen in treatment is that
the more that we can actually stabilize the forefoot,
the better that is going to cinch up, adding stability
which then in turn adds mobility,
which allows the rest of this muscular complex
to function much better.
Okay, so some functional considerations.
A lot of times when we see people do like things
like squats, lunges,
a lot of times we will start to see that the foot
may actually roll out and even flatten out.
And the reason that we see that a lot of times
is because the foot has multiple areas
where it can get this total dorsiflexion motion from.
And one of those areas is going to be this motion here.
But we can see that without this ankle moving,
I can actually get a lot of motion out of that forefoot.
And if the person is missing a good amount of motion here
and even can't get it from all of this pronation
that they have available,
they might even make up for it here.
And what ends up happening is that now,
instead of having this nice platform
where they can set their weight onto,
the foot ends up flattening out
and we end up with something that is in this plane
which then has the impact of driving the knee in
and then driving the hip in
and might even have impacts all the way up
to the rest of the chain.