- There are a few known things
that can directly cause carpal tunnel syndrome,
such as fractures, injuries to the wrist,
anything that can cause increased pressure
on the median nerve.
Other things that can be associated with it,
diabetes, rheumatoid arthritis, thyroid,
any type of inflammation in the tendons
that also pass through the carpal canal,
along with the median nerve.
This here is a diagram of the hand
with the skin stripped away
so we can see the structures underneath.
The structure in yellow here
is the median nerve
which is the nerve affected
by carpal tunnel syndrome.
The muscle here is the muscle to the thumb.
And that's also innervated by the median nerve.
There's a bridge here of tissue
called the carpal ligament
or transverse carpal ligament
which is the culprit of carpal tunnel syndrome.
And there's also other structures,
such as tendons, that pass through this.
We'll give you a better look of the carpal tunnel
if we take a transverse section of this
and look at it in a transverse cut.
Here's the back of the hand.
Here's the palm of the hand,
so palm is facing down.
Here is the carpal bones
aligned in a row that make or form
a C-shaped column.
And that C-shaped column is then bridged
by the transverse carpal ligament.
That forms a ring or a tunnel or a canal
known as the carpal tunnel or carpal canal.
There's nine tendons that pass through there
along with a nerve, and that's the median nerve.
The relevant surgery here
is cutting this transverse carpal ligament
to allow this opening here
to become greater once the surgery is performed.
In terms of activity that can cause carpal tunnel syndrome,
things that in terms of job,
repetitive type of work,
particularly more manual labor,
heavy working, repetitive,
and particularly vibrational tools,
jackhammers, power instruments, those types of things
can directly cause or exacerbate carpal tunnel syndrome.
There has been some link to other, less active,
but repetitive activities
such as typing and things like that.
Most often the symptoms from carpal tunnel
include numbness, tingling,
vague sense of pain in the fingers of the hand
and sometimes radiating up
into the forearm and arm
and sometimes shoulder even.
Other common symptoms of carpal tunnel syndrome
is loss of sleep or waking up from sleep,
causing irritation, fatigue during the day.
A lot of times patients complain of dropping things.
So anything that causes
the nerve to be compressed,
whether it be a position, wrist position too flexed
or whether it be repetitive type of activity
or even vibrational type of activity,
that can bring on the symptoms
and cause dropping of things,
inability to sense small objects
and inability to feel like
they can button their shirts,
pick up small coins,
pick up small needles,
anything of, you know, small objects.
Bikers, we'll sometimes have problems
with bikers saying that their hands fall asleep
after riding prolonged periods of time on their bike.
Driving a car, people will complain
of their hands falling asleep and having to shake it out.
And those are the types of symptoms
that we most commonly see,
the most common complaints from patients.
So, Donna, the symptoms that you're describing
are consistent with carpal tunnel syndrome.
But what I'm going to do is test
from your neck on down to your hands
just to make sure there's no other things
that could be causing this, okay?
- Okay.
So what I'm going to have you do
is take your chin and touch it to your shoulder like this.
Come over here and touch it, yep.
And now to the opposite side.
Good.
Now bring your chin down to your chest
and all the way back.
And now take your ear and touch it to your shoulder,
and same thing with the other side.
Does any of that cause any pain in your neck
or symptoms that radiate down into your hand?
- No.
- Okay, good.
When we examine a patient for carpal tunnel syndrome
or to rule our carpal tunnel syndrome,
we're also looking for other things
that may be a cause of their complaint.
So we'll do a full exam from the neck on down to the hand.
Primarily, we're looking to rule out
other common causes of similar complaints.
Then we look for arthritis in the neck,
degenerative disc disease, or spondylosis.
We'll look for any problems
such as arthritis down in the wrist,
arthritis up in the elbow,
these types of things,
anything else that we can rule out,
other common causes or other causes
that may confound or contribute
to the symptoms that they're expressing.
Carpal tunnel screening exam,
we typically look for strength in the upper extremity.
We'll test the strength of the muscles in the arm,
the forearm, the hand, particularly the thumb.
The thenar muscles are the muscles to the thumb
that provide opposition of the thumb.
And that muscle is specifically innervated
by the median nerve
which is the culprit
in carpal tunnel syndrome.
Other things that we look in terms of examination
are carpal tunnel compression test.
This is applying pressure directly over
the carpal canal and trying to elicit
or compress the nerve and elicit the symptoms
that the patient complains of.
And typically we'll look for symptoms
that radiate down into the thumb,
the index, or the long finger and half of the ring finger.
We'll also provide a test
which is hyperflexion of the wrist,
which is called the Phalen's test.
And we try to compress or kink the nerve around the carpal,
the transverse carpal ligament at that point
and try to elicit the symptoms there.
Those are primarily fairly diagnostic
of carpal tunnel syndrome.
We'll also test for muscle strength of the thenar muscles.
So we'll ask them to oppose and test the strength of those
to see if there's any weakness in the muscles
that are innervated by that median nerve.
And finally, we'll test the sensation out in the fingertips.
And we do that by a two-point discrimination,
which is basically asking the patient
to discriminate between one and two points
separated by a given distance.
And there's a normal range
that you'd like them to fall within
and be able to distinguish two points from one.
I usually ask them about their past medical history,
what types of medical conditions
that may contribute to carpal tunnel,
such as diabetes, such as thyroidism,
high blood pressure.
Those are the types of things.
We ask them about their vocation,
what type of activities that they perform
outside of work.
Other things we'll ask them
is nighttime symptoms, does it wake you up from night?
How often does it wake you up from sleep?
Does this interfere with your daytime?
Are you fatigued and tired throughout the day?
We'll commonly ask them about their symptoms
of numbness and tingling or others.
Do you have numbness and tingling?
Do you have pain?
Do you have problems buttoning your shirt,
picking up small objects?