How To: Hand & Wrist - HD

Introduction

Hi, my name is Sandra Allison,
and today I'll be showing you how
to scan the hand and wrist.

Scanning the Flexor Tendon

When scanning, we're gonna start with a finger
and we're gonna start with a flexor tendon.
It's important to do the scan with a patient comfortable.
I prefer to have the patient sitting across from me
with a table in between us and with a rolled towel
or a roll to keep their hand comfortable
and to avoid interference with the table on the transducer.

Okay, so I just place the gel on the finger
and I try to localize the flexor tendons.
You should see two which may not be
easily distinguished from each other.
There's a superficial and a deep tendon.
You can flex the finger, the DIP joint
to isolate the deep flexor tendon.
And you can also use this to evaluate for normal
or abnormal tendon lighting motion within the sheath.
Okay? And you can scan down towards the insertion
of the deep flexor tendon onto
the distal phalanx.
Here's the insertion shown here.
And at this point we only have one flexor tendon,
which is the deep tendon scanning up.
We start to encounter the superficial flexor tendon,
which we should see fully at the level of proximal phx.
And here we are now at the metacarpal phal joint
with both the superficial and the deep flexor tendons.

Evaluating Pulleys and Trigger Finger

Now, when scanning for the pulleys,
you look at the A one pulley at this level,
and you may see it in the long axis
as a focal thickening in the flexor tendon sheath.
This is much easier to see in the transverse plane
as a halo or a focal thickening around the flexor tendon.

Now crossing over the metacarpal phal joint,
we see the absence of a halo
as there is no pulley in this location.
And then distally, we see another thickening,
which represents the A two pulley.
Now, the pulley is only present
or the proximal portion of the phalanx, where you can see
that the tendon to phalanx distance is very little
as opposed to over here where the tendon
to phalanx distance is increased because there is no pulley.

When you're evaluating for trigger finger, again, you can
passively or actively flex the fingers
to observe for normal
or abnormal tendon sliding within the tendon sheath.
Do the other side. Okay.

Scanning the Extensor Tendons

Now we can also evaluate the extensor tendons
with the same method.
I prefer to start at the level of the metacarpal head
as the tendon is more easily identified
As this thin band distally.
It's thinner, but can still be
identified with careful scanning.

Now the sagittal bands just pull your finger
over and bend a little.
There are very superficial structures
and it may help to use a standoff pad or heaped up gel.
And the bands can be seen as hypo coic structures
that are stabilizing the extensor tendon onto the phalanx.

To evaluate for subluxation, you can scan with a patient
with the fingers extended, and then with a fist formed,
you can see that the tendon remains centered
on the metacarpal and is not subluxed.

Scanning the Median Nerve

Now we can also scan the median nerve,
which is the most common nerve
affected by an entrapment.
And I again like to use a rule or a rolled up towel
and have the patient drape their wrist over the roll.

The median nerve can be distinguished from the adjacent
flexor tendons, which are more echogenic.
You can also confirm that these are tendons.
By rocking the transducer
and showing anti isotropy, there is some anti isotropy
with a nerve zone to a lesser degree.
The nerve has a distinctive vesicular pattern,
and you can see the nerve as it sits in the bony
carpal tunnel with the re aum extending across
the nerve can be scanned in the transverse plane as distal
as possible and as proximal.
So you can follow it, The arm,
and then of course you would evaluate the
nerve and the long axis.

Okay, we look at some chairs.
By turning the transducer well, well scanning the nerve
and again, evaluating it
for differences in thickness or appearance.

Scanning the Ulnar Collateral Ligament

One other thing that you can scan
is the ulnar collateral ligament at the metacarpal
phal joint of the thumb.
And you can either have the patient extend their thumb
or you can turn the roll and drape their hand over the roll.
Okay.

And you can place a transducer across
the metacarpophalangeal joint
to show the ulnar collateral ligament.
You can evaluate for laxing in the joint
if you suspect suspected tear by stressing the joint
and observing for abnormal increased joint space.

Conclusion

That concludes basic evaluation of the hand
and wrist with ultrasound.
Thank you.