Hello, my name is Dr. Deborah setter.
I'm going to demonstrate the sensory exam.
Thank you to Dr. Laughlin for
assisting with today's demonstration.
Alright, so for sensation,
It's important to remember that you have
your dorsal column medial lemniscus
pathway that conveys position and
joint joint position and vibration sensation.
We also have our spinal thalamic track that
conveys pinprick and temperature sensation.
So allow me to demonstrate how
I approach the sensory exam.
First, I like to check temperature sensation.
It's Kotlin for neurologists to use
their cold tuning fork and just touch it
on the distal aspect of the arm and ask,
does this feel cold to you comparing
right to left, and then on the foot?
This is how I do it in
a normal patient just to make
sure that cold sensation
is working appropriately.
If I have a patient who has
abnormal sensory findings on their exam,
then I want to check
it a couple of extra ways.
Here at Mayo.
We actually have these little disks.
One it's kept on a cold metal shelf
and the other that's kept on
a little heated shelf.
So that way they can test and tell you
if they feel something cold or hot.
So I'll have the patient close their eyes.
Tell me is it cold or hot?
Cold.
Hot.
And then I could do a couple
of different trials to
make sure that the sensations consistent.
Another thing that I'll check
if someone's having issues
with feeling temperature is
I'll give them an area where it's normal.
Typically, I'll check on the chest
because it tends to be well-preserved.
And then I say, okay, this is cold, right?
That's cold.
And then there if they can't feel it,
tell me where it feels as
cold as it does on the chest.
And that way I can help figure out where
is that sensation normalized.
So that's checking temperature.
Next I go for testing vibration.
If it's a normal patient,
I'm just doing a quick neurological exam.
I'll tap the tuning fork
just a little bit to get
a little vibration to
hold it against the joint.
It's important I want to make sure
that I'm pressing the fork to
the distal interphalangeal joint
and I'm also holding
my distal interphalangeal joint underneath
her so that way
I can feel the vibration myself.
That vibration information is going
into her finger and my finger.
And then I asked her, Does
this feel buzzy to you?
If it's a little bit buzzy
and she can feel it.
I feel comfortable in testing.
If I really want to know vibration sensation,
I'll do a large strike and
then asked her to tell me when it stops.
Sometimes the tuning fork can
vibrate for quite a long time.
So a little trick is you
move your finger up a little
bit and that'll get
it to stop a little bit quicker.
And then I'll see, is it about
the same time for us or does she have
Shi it extinguishes for
her before it extinguishes for me,
I'm using myself as a normal control.
Another trick, sometimes when patients are a
little bit inconsistent on the exam,
sometimes I won't tap it.
I'll just kinda mind that I'm tapping
it to make sure yes, they're accurate.
They're telling me.
Okay.
It's not vibrating.
And then okay.
Here it is vibrating.
What do you feel as a buzzy are not buzzy.
Again, I'll be sure to test
and the fingers as
well as the distal joint in the toe.
That's vibration sensation.
Next is joint position sense for
this positioning of
the hands is very important.
I want to make sure that I'm stabilizing that
distal interphalangeal joint and then
holding onto both ends of the finger and
make sure that that patient is
nice and loose as I wiggle them,
I'll have the patient close
their eyes and then tell me,
Do they feel their finger move up,
down or they don t know?
Down, down.
It's important to give them
a couple of different trials.
Again, to check for that consistency.
There's another trick you can use
is you have the patient close their eyes
and then you do really teeny movements
and gradually make it bigger and bigger.
And you ask the patient to tell you,
when do you start to feel the movement?
Eyes closed? When do you start to feel it?
Yeah.
Whereas if people have reduced
joint position sense,
they'll need much larger amplitude movements
before they can feel it.
I do the same technique in
the fingers as I do on the toes.
If someone doesn't have
any joint position, sense that the finger,
then I need to move up the arm or move up
the leg to see when do they
recover joint position sense.
I can stabilize at the wrist
and hold the hand,
move the hand up and down.
I can stabilize at the elbow.
Move the arm at the elbow up and down.
Same in the feet.
In the feet here.
I'll grab at the distal
joint and wiggle the toe up or down.
If they have trouble feeling there,
hold onto the ankle,
onto the medial and lateral malleolus,
lifted up and down.
If they can't feel it there and
go up to the knee, move up and down.
Same with vibration sensation.
If someone doesn't feel it
here at this joint, I'll move up.
Do they feel it there?
When do they start to feel the buzz?
Same and the leg?
I can go down here.
Do they feel the buzz?
If they don't feel it there?
Go up to the ankle,
go up to the pellet, the patella.
You can even go up to the iliac crest on
patients to check
for that vibration sensation.
Next I test pinprick sensation.
I always preface for my patients
that I test the pokey sensation
but I don't break skin.
I hold the hand like this and then I'm
tapping on the dorsum of the finger there.
If I have a patient with a sensory complaint,
I'll also make sure to test
the pads of the finger.
But in general, for a normal patient,
I'll go with the dorsum of
the finger and then just ask if they
feel the Polk comparing right,
left, and then the toes.
If there's any sensory issues, again,
I want to trace up
the limb and see
when does it start to feel pokey.
I'll also sometimes do
a little poke on the chest
to convey this is what normal feels like.
There's the normal pokey sensation.
When does it become pokey
like it is on the chest.
Next is light touch sensation.
This covers a couple
of different sensory modalities,
but it's really useful in
our patients with neuropathy.
Neuropathy.
So for this, I have
the patient close their eyes
and I pull out just a little teeny wisp of
cotton and I trace it lightly across
the fingers and ask when
do they feel the cotton.
And then I keep tracing upwards.
If someone has neuropathy,
keep going up to find out where do
they regained sensation of the cotton.
Tracing along the hands up the arms.
Same in the feet, up the legs.
That is a complete sensory exam.
So for joint position sense,
There's a couple of other tricks in
the neurological exam to test for this.
One is when I'm having the patient
have their arms outstretched
and their eyes closed.
Sometimes you can see a feature
called pseudo apitosis,
where the fingertips will start
to float around in space.
That's because they've lost
joint position sense.
You can even see the arms
start to float in the air.
Again, that's that lost joint position sense.
Another trick is when their eyes are closed,
have them touch their nose.
And you can see if they can't quite
figure out how to
touch their nose right on the dime.
That's another sign that
their joint position sense is affected.
You can also see it when testing
Romberg sign you have the patient stand
up nice and straight
and ask if they feel wobbly,
close their eyes, and then
you'll see that sway with Romberg.
So those are a couple of different ways to
look at joint position sensation.
If I'm in the emergency department
are really crunched
for time examining a lot of
stroke patients in the morning.
There's an additional shortcut where you just
focus on light touch, using your fingers.
For this, you just lightly brush.
And again, I want to test that distal part of
the arm if they can feel me just delete,
I can assume that they can feel me
proximately and I'll have
the patient close their eyes.
Tell me which side I'm touching.
Right?
Left.
Both.
It's important to test in
that order because I'm making sure yes.
She can feel me on the right.
Yes, she can feel me on the left.
But if I touch both sides
and she can only feel the right,
That's how I know if there's neglect.
I'll do the same and the arms
and then on the legs.
So let's kinda your shortcut when
you're really crunched for time.
And this wraps up the sensory exam.