00:00
Now, let's talk about a case.
00:02
This is a 45-year-old
right handed man
who works as a software engineer
and presents with new complaints
of numbness in the hands.
00:09
He says that for
the past six months,
he has had numbness in his hands.
00:13
This initially began in his
right hand and he's right handed,
and then more recently,
he developed symptoms
in his left hand.
00:19
He says that the symptoms are
worse at the end of the day
and awaken him at night,
where he will
shake his hands for relief.
00:26
He reports numbness and tingling in
the first three digits of his hands.
00:30
So the first, second,
and third digit in each hand,
the fourth and fifth,
the fifth digits are spared.
00:36
Over the past few weeks,
he has noticed subjective weakness
in the right hand
with opening jars
around his home.
00:42
Examination shows
no muscle atrophy,
he does have mild weakness
in the thumb
and index finger with opposition.
00:49
There's reduced sensation
over the first three digits,
no symptoms in the lower extremities
and normal deep tendon reflexes.
00:56
So what's the diagnosis?
Well, there are a number of things
to think about in this case.
01:01
The first is the distribution.
01:03
This problem involves
the first three fingers
and not the fourth and fifth digit,
and that is very sensitive
and specific for a problem
affecting the median nerve.
01:14
The median nerve innervates,
the thumb, index, and middle finger
and does not provide
nervous innervation
to the fourth and fifth digit.
01:24
In addition, we also see that
this problem is worse at night,
and he wakes up
and shakes his hand,
which is something
we commonly see in patients
with carpal tunnel syndrome.
01:32
And we don't have
other findings to suggest
a more systemic polyneuropathy.
01:36
There's no symptoms
in the lower extremities
and normal deep tendon reflexes.
01:40
So what's the diagnosis?
Is this carpal tunnel syndrome,
AIDP or Guillain-Barre syndrome,
diabetic polyneuropathy,
or a cervical radiculopathy?
This is not the typical presentation
for diabetic polyneuropathy.
01:56
That's a chronic onset.
01:58
Length dependent polyneuropathy
that begins in the legs
and ascends into the hands.
02:02
And we don't have any of those
symptoms present in this patient.
02:06
Cervical radiculopathy could cause
symptoms in the upper extremity,
but it would be quite
uncommon to have onset
of upper extremity symptoms
in both hands at the same time.
02:16
And typically central cord problems
affect a tape length distribution
as opposed to the distal hands.
02:22
And then lastly,
AIDP or Guillain-Barré
presents with a sudden rapid
ascending polyneuropathy
and not focal neuropathic symptoms
only in the hands.
02:33
Well, this is a classic
and typical presentation
of a patient with
carpal tunnel syndrome.