So we're gonna talk a little bit
about the thoracic spine
There's some general characteristics of
the spine that you could appreciate.
The thoracic spine is primarily a kyphotic curve
which means that it is convex posteriorly.
This convexity is present from birth.
It is relatively immobile.
It's not really mobile because it is
connected to a rib cage
and the rib cage limits the ability for
motion and movement in the region.
It is a transition zone between
the cervical and thoracic regions
and it helps to form the posterior portion
of the thorax.
We could divide the thoracic spine
into functional divisions.
From T1 to T3,
this is the cervical thoracic junction.
It is slightly lordotic.
Whereas from T4 to T9, this is where we consider
the true thoracics and this is more kyphotic.
And then from T10 to T12,
it's a little bit more backward bending
this is where the thoracic spine starts
to transition to the lumbar spine.
You could usually find an apex around T5 to T6.
So the rule of threes helps us
to have a better understanding
of the relationship between the spinous
process and the transverse processes.
This is important because in much of
what we do with osteopathic diagnosis,
we are going to be utilizing the transverse
processes to identify for somatic dysfunction.
Remember, for somatic dysfunction,
we're looking for tissue texture changes
TART changes which stands for Tissue texture changes,
Asymmetry, Restriction of motion and Tenderness.
And so if you find these somatic dysfunctions, you're
gonna be looking for them along the transverse process.
Once we find a somatic dysfunction
along the transverse process,
it's important to understand the relationship between
the transverse process and the spinous process
so we know anatomically where our level is.
And so there are certain key landmarks
to find along the spine
where the spinous process helps us identify
which level of the spine we're located.
So, if you think about the T1 level, it's
right below C7 which is vertebra prominens
which is easier to find if you have
someone flex your head forward.
If you look at the scapula and
at the spine of the scapula
if you come directly at the same level of the
spinous scapula, that would get you to T3.
If you are at the inferior border of
the scapula, that would get you to T7.
And if you find the 12th rib and track yourself
medially to the spinous process, that would be a T12.
So it's easy to identify these
landmarks for the spine midline
but when we diagnose for somatic dysfunction,
we're pushing on the transverse process.
So most of the time we need to
find the transverse process level
by first identifying the dysfunction and then going
backwards and seeing where the spinous process is.
And this takes us to the rules of three.
So the rules of three helps us to
find where we're located in the spine
based on the spinous process and
transverse process relationship.
So the rules of three, you're looking
at 3 thoracic vertebrae at a time.
And so, from T1 to T3, you will find the spinous process
pretty much at the same level as the transverse process.
From T4 to T6, now the spinous process start
to shingle down a little bit more inferiorly
and you'll find the spinous process is halfway between the
transverse process of that level on the one below it.
From T7, 8 and 9, here the spinous processes are
at the level of the transverse process below it.
So it's moving a lot more inferiorly
and so for instance,
if I am looking for the spinous process of T7,
I'm going to find that at the level of the body of T8.
T10 functions like T7 to 9, so the spinous process
is going to be found at the level below at T11.
T11 is more like T4 to T6 so this spinous process
will be found halfway below between 11 and 12.
and T12 now is gonna be at the
same level similar to T1 to T3.
So now let's take a look at how you would
utilize this in clinical practice.
So if you have a patient and you found tenderness
at the right transverse process in the back
and you note that's at the level
of the thoracic spinous process
that's in line with the inferior boarder
of the scapula,
What is the level of the the
transverse process you palpated?
So here we have to work backwards.
First we have to identify
the spinous process level.
So like we said before, the inferior border of the scapula
is gonna be in line with the spinous process of T7.
So if you have the spinous process of T7, what
is the transverse process at that same level?
And so going back to rules of three,
you know that because the spinous process
is going to be 1 full level below,
you know that that's going to be
the transverse process of T8.