Sonography of Common Shoulder and Elbow Pathology - HD

Introduction

Hi, my name is Sandra Allison and I'm from Washington DC
and I'll be lecturing here today about sonography
of the shoulder and elbow.
I have no disclosures
and my objectives are to discuss common pathology associated
with shoulder and elbow pain, as well
as review sonographic appearance of normal
and abnormal nerves.

Imaging the Shoulder: The Painful Shoulder

When imaging the shoulder, I'm going
to discuss particularly the painful shoulder
and I'll be focusing on rotator cuff
and rotator cuff tears tendinosis involving the rotator cuff
as well as issues involving the biceps tendon.
And for the purposes of time,
I will not be discussing joint effusions
or other effusions such as bursal effusions in the shoulder.

Normal Appearance of the Rotator Cuff

Now the normal appearance of the rotator cuff we see here
on this short axis and long axis view of the cuff.
A normal tendon is hyperechoic or very echogenic.
You can see the fine parallel white lines,
which are the echogenic fibrils.
The surface of the tendon is convex
and the underlying bony cortex is smooth.
Here in the short axis view, again we see a smooth
humeral head cortex.
We see the rotator cuff in one layer
and then moving on, this is the deltoid muscle here and here
and then the subcutaneous tissues.

Full Thickness Rotator Cuff Tears

Now for full thickness tears, we will be looking
for complete absence of the cuff
or a defect extending throughout the cuff.
The defect is typically hypoechoic
and may be filled with fluid.
Sometimes you don't see the fluid,
but rather there'd be an area of volume loss,
which can be accentuated by compression.
Sometimes you may see fluid in the subdeltoid bursa as well
as within the biceps tendon sheath,
oftentimes in the acute setting.
Now again here we are looking at the rotator cuff.
This is a long axis view and a short axis view.
And if we're looking at the layers of the shoulder,
this is the subcutaneous skin
and tissues here is the deltoid
and here is the rotator cuff with a defect
that is hypoechoic.
You can see that this fluid is extending into the
subacromial subdeltoid bursa
and outlining the free edge of the tendon.
And here there's a little bit of irregularity on the
greater tuberosity of the humerus where the
tendon inserts the short axis view.
We see again, fluid filling a defect.
Here we see rotator cuff and rotator cuff.
This area of the rotator cuff is missing.
One caveat is to not confuse this layer,
which is the cartilage layer with a portion of the cuff
and call this a partial thickness tear.
Again, moving on, this is the irregular
pearling humeral head cortex.
Here we've got the deltoid subcutaneous fat and skin.
Now sometimes the fluid is not anechoic
or may contain echoes,
either
because of blood
or debris.
And in this case here we see this is a short axis view
of the rotator cuff.
Here we see intact cuff,
but in this area we are missing a portion of the cuff.
If we're not sure, you can accentuate this defect
or evaluate if this is a full defect by compression
overlying, this is the deltoid,
the subcutaneous tissues along with the skin.
This is the biceps tendon over here.
This is a comparison normal view
where you see again the full cuff extending across the
humeral head
and covering that head completely.
Now here's a patient who had presented
with longstanding weakness
with abduction of the arm.
And if you're going to count the layers
as we have been doing in the prior slides,
we've got the skin here
and the subcutaneous fat,
we have the deltoid muscle overlying.
Over here we have the humeral head.
And then you can see we are missing the typically seen hyper
echoic rotator cuff.
In this case, this may be a synovial thickening
of the residual subacromial subdeltoid bursa.
Maybe a small amount of fluid,
but in essence we are missing the entire rotator cuff.
This is a full thickness rotator cuff rupture.
Now the same rules apply if you're evaluating a
patient with a replacement.
In this case, we are looking at the skin
and subcutaneous fat.
We've got the deltoid muscle here
and this hyperechoic structure with some
dirty shadowing is the humeral head component
of the shoulder replacement hardware.
And you can see again that we are missing that other layer
that typically covers this hardware,
which is the rotator cuff.
Also full thickness tear involving a patient
with total shoulder shoulder arthroplasty.

Partial Thickness Rotator Cuff Tears

Now with partial thickness tears, again,
it may be hypoechoic or mixed if there's debris
or may even look hyperechoic depending on
how you're imaging a patient.
And the tear may be either on the bursal side,
which is more superficial
or on the articular side of the cuff.
This is often associated with underlying bone irregularity
as with the full thickness tears.
And when describing this in your report,
you should include the location, for example,
which tendon is involved, is it the anterior
or the superior portion of the tendon, the percentage
through the cuff thickness, whether it's 50 percent
through the cuff or less than 50 percent or 25 percent,
and then the width of the tendon that is involved.
Okay, so here we are moving along,
looking at a bursal surface tear.
We're looking at the skin and subcutaneous fat.
We've got the deltoid muscle here.
We've got the rotator cuff with a small hypoechoic defect
along the bursal side of the cuff.
Here we're looking at the underlying humeral head.
If you're not sure whether this is pathology
or if this is debris
or to further evaluate the degree of cuff involvement,
you may compress onto that defect
and see if you can splay apart the free edges of the tendon.
But again, you can see that there is a area
where the cuff is missing here.
This is a bursal surface tear
and there's even a little bit
of fluid here in the overlying subacromial subdeltoid bursa.
And when the tear is on the other side,
it is called an articular surface tear.
So here we see a hypoechoic
or anechoic defect in the tendon does not
extend all the way through.
In this case, the bony irregularity is minimal.
This is an articular surface tear
involving the rotator cuff.
Now sometimes the tear is within the substance of the tendon
and that can be called intrasubstance tear.
And here we see these linear hypoechoic defects within the
tendon extending throughout the substance
of the infraspinatus tendon in this case.
One more example showing abnormal on this side,
the right side and normal on the left side,
this patient presented with acute
shoulder pain, long axis view.
On top here we have the rotator cuff with a defect
overlying deltoid
and then the rotator cuff,
that's normal extending all the way across the humeral head
and inserting onto the greater tuberosity.
Short axis view, the supraspinatus is missing.
The infraspinatus remains.
Here is what it looks like on the normal intact side
where we see a complete cuff covering the humeral head.

Rotator Cuff Tendinosis

Moving along the tendinosis.
Now with tendinosis, the tendon is thickened
and heterogeneous.
You may see some nodular hypoechoic or even anechoic areas.
Over time, calcifications may develop within the tendon,
which then can lead to interstitial tears or splits.
As I showed earlier, the presence
of increased doppler flow is variable depending on the
patient and whether they
the problem is acute or chronic.
Now this patient presents with pain with overhead reaching.
We're looking at the supraspinatus tendon in this case
and you can see that the tendon is heterogeneous,
it is hypoechoic compared to a normal.
We've lost the normal fine parallel echogenic lines which
represent the collagen fibers.
And we have this focal area
of decreased echogenicity right here overlying
the greater tuberosity.
Now if you're not sure whether this is a tear,
you may compress on this area
to see if you can find a convexity
or flattening of the contour of the tendon,
or you may rotate the transducer
or rock the transducer
to bring out any potential anisotropy.
And here we see we have a little bit
of fluid in the overlying subacromial subdeltoid bursa,
but this is a case of tendinosis involving
the supraspinatus tendon.
Now with tendinosis, the tendons are thickened
and there may be compression of the tendons
and the overlying bursa between the greater tuberosity
and the lateral edge of the acromion process
or even the coracoacromial ligament.
And this manifests as pain sometimes while sleeping,
but also with overhead reaching
which extends toward the outer deltoid.
It has the same symptoms as plain tendinopathy
and patients may sometimes present with atrophy
of the muscles of their back top and back of shoulder.
So here's another tendon that is significantly thickened.
It's hypoechoic and heterogeneous.
The underlying bony cortex is irregular.
We see nodular hypoechoic areas within the tendon.
Sometimes over time you may see
focal hyperechoic deposits within the tendon,
which may represent calcifications.
And you can see here is the overlying acromion which
may impinge or compress onto the tendon when the patient
is abducting their arm.
Now one can test for this dynamically.
You can have the patient abduct their arm
and watch it in real time.
I these are stills,
but here is the right arm with the arm in abduction
and you can see that the rotator cuff has slid pretty much
completely underneath the acromion.
Whereas on this side, the patient is unable
to abduct completely
because there is thickening of the overlying bursa.
And sometimes at real time you can watch this bunching up
or ratcheting as it is trying to slide
underneath that acromion.
Here's another patient who presents with symptoms
of pain at night and pain with overhead reaching.
Here is the acromion possibly
with a small spur.
We've got the humeral head
and we've got the supraspinatus tendon
and you can see that there is focal thickening
of the tendon due to the presence
of calcification within the tendon.
And when the patient tries to abduct the arm,
the tendon is unable to slide completely
underneath acromion due to impingement
and blockage from this intratendinous deposit.
Now sometimes the deposits within the tendon may be
paste like and this is also another form
of calcific tendinosis
or calcific tendonitis as it's called.
And these patients may present with acute shoulder pain
and decreased range of motion.
In this case, you can see this deposit
that almost looks like it's on the superficial
or on the surface of the subscapularis tendon.
It may appear very hyperechoic
with not much shadowing and it may be a budding
or tenting the overlying bursa.
This is the long axis view
or the short axis view, I'm sorry,
this is the biceps tendon.
And here it is the long axis view
of the subscapularis tendon sitting right on its surface
abutting the subacromial subdeltoid bursa.
Now over time, that deposit may
evolve in its appearance
and the center may become more hypoechoic to anechoic
with posterior acoustic shadowing.
This is another case of calcific tendinosis involving
the infraspinatus tendon in this case.
And here we have that deposit in long axis view.

Biceps Tendon Pathology

Moving on to the biceps tendon.
Now that we know what tendinosis
and tendon ruptures look like, we can apply that knowledge
to other tendons in the body.
In this case, the biceps tendon here is the
normal biceps tendon.
In short axis sitting in the bicipital groove,
we have the lesser tuberosity
and the greater tuberosity,
the subscapularis tendon is over here
and the overlying deltoid in long axis we have the humeral head
with the biceps tendon as it's going through the groove
and extending distally and then the overlying deltoid.
Now one other pathology to discuss with the biceps tendon is
that at times it may either dislocate
or sublux out of its bicipital groove.
Okay, so now we have another patient
with anterior shoulder pain
and we can see that the biceps tendon has lost its normal
hypoechoic appearance.
In this case it is thickened hypoechoic.
There is increased flow to this tendon on doppler imaging.
In the long axis view, we see that the tendon is hypoechoic
with nodular areas also, again
with increased vascularity this time on power doppler
imaging and more importantly, the patient will report
that their tenderness is right in
the area where you're scanning.
When you're scanning this tendon,
sometimes the tendon sheath may distend with such
as in this case here is the bicep tendon, possibly
with a hypoechoic or nodular area and fluid
and possibly debris within the tendon sheath.
In long view you can see the hypoechoic collagen fibers
and some loss of architecture
with nodularity within the tendon and fluid in the tendon
sheath. This is biceps tenosynovitis.
The tendon sheath may become thickened, may develop webs
or adhesions or synovium, and the fluid may not always be simple
but sometimes complex.
And here you can see this tendon again with some loss
of architecture and thickening of the tendon sheath.
If you use power doppler, you will see increased vascularity
in this patient who has biceps tenosynovitis.
Now when you see fluid in the biceps tendon sheath,
the first thing you should think of
and look for is a rotator cuff tear
or rotator cuff pathology.
Whereas primary biceps tenosynovitis such as the setting
of rheumatoid arthritis is much less common.
Now sometimes when you're looking at the bicipital groove,
you just simply will not see the biceps tendon.
In this case, you may suspect a biceps tendon rupture.
You can confirm this by looking inferiorly
and following the long head of the biceps muscle
to see a free edge of a tendon.
Or in this case when it's chronic it may often be difficult
to find the tendon, but you can see
that the greater tuberosity
and lesser tuberosity have an irregular surface.
Sometimes can be seen with arthritis,
but also with underlying tendon pathology.
Now this patient presents with shoulder pain, especially
with external rotation
and I'm comparing a normal bicep tendon.
Here you see the normal tendon sitting in the bicipital
groove and in this case we're looking at
the tendon which is no longer sitting within the groove,
but rather displaced medially,
which is the most common location
for biceps tendon subluxation or dislocation.
When you see the biceps tendon dislocated medially,
you should take care to look
and see whether there is an associated subscapularis tear
as the tendon may dissect within the fibers of
that subscapularis tendon.

Imaging the Elbow

Moving on to the elbow, it is useful
to divide the elbow into compartments the anterior lateral
medial and posterior compartments.
Unlike the shoulder where pathology may present
over the deltoid or posteriorly
or extending anteriorly in the elbow.
When the patient presents with pain in a specific location,
usually the pathology is in that compartment,
directly correlates with the pain when you're doing the
examination and when you're scanning the patient.
And you can tailor your examination
to specifically address that clinical question
because you know you can localize it to that compartment.

Medial Elbow Pain

Now, in evaluating for medial elbow pain,
the two most common structures we've been looking at is the
ulnar collateral ligament, which is
labeled number four here on this diagram by Dr.
Netter or the common flexor tendon
which inserts on the medial epicondyle
and is represented by this white structure.
Under the arrow Here are what the
those normal structures look like with ultrasound.
Here is the ulnar collateral ligament, this hypoechoic band,
relatively hypoechoic band
that is extending across this joint.
The common flexor tendon is superficial to that
and you can see it extending onto the medial epicondyle.
Here you see the tendon
with the fine parallel echogenic fibers or white lines.
And here we look at the myotendinous junction
as it extends into the muscle.
Here's another view of that tendon,
but you can see that it fans out over a wider area
of insertion, just like you see in this diagram over here.
Now for a partial or a tear involving the ulnar collateral
ligament, we will be looking at the deeper portion of
that complex
and you can see that there is a defect in this
ligament right here with the remaining portion
of the ligament sitting in this location.
Now for this patient we actually, he presented
with medial elbow pain
and you can see that there is a calcification in the
expected location of the ulnar collateral ligament.
And in this case, this patient was a javelin thrower
during his college years.
And this is the chronic appearance of longstanding tear
or injury to that ulnar collateral ligament.
Now medial epicondylitis, which is a misnomer
because it is actually not inflammation as the itis implies,
but rather tendinosis involving the common flexor tendon
which inserts on that medial epicondyle.
It is also known as golfer's elbow.
You may see degeneration within the tendon just like I
showed with a rotator cuff where there is heterogeneity
of the tendon thickening, nodular hypoechoic areas
or loss of normal architecture, you may see some swelling
or redness on inspection
and this will directly correlate with the site of pain.
Again, to remind you, we are looking at this white structure
on the Netter diagram, which is the common flexor tendon
as it's inserting onto the medial epicondyle.
These are the normal structures
and in this comparison,
patient presenting with medial elbow pain.
You see that that common flexor tendon is hypoechoic
and thickened with nodular areas of decreased
echogenicity, possibly
with some punctate echoes within the tendon.
With doppler you can see that there is increased flow within
that tendon and more importantly the patient will say,
this is where they are experiencing their symptoms.
This is the normal comparison medial epicondyle
and common flexor tendon.
Another case patient presented with medial elbow pain.
Again, you can see there's some normal tendon here,
but this portion of the tendon is hypoechoic.
There may be a little bit of adjacent fluid,
but in this case there's increased vascularity in the power
doppler, we don't see a discrete tear
and this is another case of common flexor tendinosis
or golfer's elbow.
One last case in this case.
More to illustrate that the underlying cortical surface at
the medial epicondyle may appear irregular
and you may see calcification in the tendon
in the chronic setting.

Lateral Elbow Pain

Moving on to the lateral elbow structures
that may be involved include the common extensor tendon,
which is the structure right here,
the lateral collateral ligament complex,
which is a deeper structure.
You may have pathology involving the radial nerve
and its motor branch, the posterior interosseous nerve.
And these are other lateral structures
that I won't be covering for this lecture.
So lateral epicondylitis, now
that we've reviewed medial epicondylitis,
it is the same appearance
but now involving the common extensor tendon
as it inserts on the lateral epicondyle.
This is also known as tennis elbow.
There may be tenderness to palpation
and when you're scanning the patient they will confirm
that you are looking at the area of symptoms.
And again, as with any kind of tendinosis,
you will see tendon thickening,
a heterogeneous appearance to the tendon possibly
with hypoechoic areas
and possibly increased vascularity on power doppler.
We are looking at this structure over here,
which is the common extensor tendon.
We see that it is, there is some loss of architecture here,
decreased echogenicity in this area.
There's disorganization or loss of architecture
and increased vascularity on power doppler
and this is a patient with lateral epicondylitis.
Now in this case, if you look closely, you can see hypo
echoic defects within this very heterogeneous tendon.
There's calcifications
or an enthesophyte here on the lateral epicondyle
and some increased vascularity on power doppler.
So this is lateral epicondylitis
or tendinosis with interstitial tearing.
Sometimes the tear may be focal
and you can report a partial tear,
but you can see there's a defect in this tendon,
which also appears irregular hypoechoic
and heterogeneous with increased vascularity in power.
And just to show you the normal tendon,
the normal tendon here is extending over
and inserting onto the lateral epicondyle.
The deeper structure right here
is the radial collateral ligament, which you can sometimes
evaluate for tear or injury.
Here's another view of
that lateral ulnar collateral ligament
or radial collateral ligament.
It is deep to the common extensor tendon
and in the setting of a tear you will see a defect in
that area possibly with fluidness In this image
that is provided by Dr.
Nazarian. Here's another patient who presents
with lateral elbow pain
and you can see that the overlying common extensor tendon is
intact, but there is fluid
and the free edge of a torn radial collateral ligament.
Now sometimes patients with lateral elbow pain have a normal
common extensor tendon
but rather have pathology
of the posterior interosseous nerve.
The posterior interosseous nerve is the deep branch
of the radial nerve.
So here we've got the radial nerve coming down the arm
around the spiral groove of the humerus coming
around and then dividing.
The superficial branch is right here,
which is the sensory branch.
And then we have the deep motor branch which dives
between the deep and superficial heads
of the supinator muscle underneath the arcade of Frohse.
And this is the posterior interosseous nerve which may be
compressed as it dives into that location.
Here is a comparison image of a patient who presents
with lateral elbow pain.
On the right we have the normal posterior interosseous nerve
depicted in long and short axis
and indicated by the orange arrows.
So here we've got the nerve extending down
and then piercing the supinator.
We have a superficial and deep portion of the supinator
and the nerve as it inserts.
Here's what it looks like in short axis in comparison on
this side where the patient is feeling the pain, you can see
that that nerve is thickened
and you can see that it's thickened proximal to
where it pierces that muscle.
That is a classic appearance for nerve entrapment
or nerve impingement,
and in this case a patient with impingement
or entrapment of the posterior interosseous
nerve anteriorly.

Anterior Elbow: Distal Biceps Tendon

We can look at the joint recesses for effusions.
We can look at the biceps tendon, the distal biceps tendon
as shown on this image for rupture, tear or tendinosis.
We can look for fluid in the bursa.
Look for nerve pathology either involving the median nerve
or the lateral antebrachial cutaneous nerve
or look at the muscles in this location.
For the purpose of this lecture,
I'll be discussing the biceps tendon.
So the biceps tendon is a little bit harder to see
in this location mainly
because the tendon does not assume a parallel course
to the transducer,
but rather it dives deep
as it inserts onto the radial tuberosity and
therefore we don't see those
normal collagen fibers that well.
The tendon also normally fans out at its insertion,
which should not be confused with pathology.
Now in this case, patient presents with anterior elbow pain.
Just to show you on this Netter diagram here is
that tendon coming down
and inserting medially along the radial tuberosity
because it inserts medially,
it may assist you in your evaluation to have the patient
supinate their arm
to bring that edge out.
Now here we see the biceps
or the distal biceps tendon coming down.
It looks relatively normal in this appearance up here,
but as it comes down you see
that the tendon appears thickened and hypoechoic
and there's a small amount of fluid
where it is torn off its insertion from the
radial tuberosity.
This patient experienced a sudden pop while
at his karate class.
You can see a comparison normal distal biceps tendon
as it's coming down and inserting onto the tuberosity.
And in this side the affected side,
you see the tendon coming down, becoming thickened
and redundant
as it is partially retracted from its
insertion, which is down over here.
So here is that free edge of this distal biceps tendon,
which has pulled off the bone in this complete distal
biceps tendon rupture.

Posterior Elbow

Posteriorly, we'll be looking at the triceps tendon,
which is this structure right here
can also look at the posterior joint recess
for fluid collections there or within the olecranon bursa.
And we can also look at the ulnar nerve for evidence
of ulnar nerve entrapment in patients who present
with posterior medial elbow pain.
Now that we've reviewed several cases of tendinosis,
you can apply that concept to evaluating the triceps tendon.
In this patient with posterior elbow pain,
we have the triceps tendon coming down inserting onto the olecranon,
but we can see that there is a decreased echogenicity in
a portion of the tendon.
The tendon is heterogeneous with hyperechoic deposits
or calcifications within the tendon
and an osteophyte forming from the olecranon process.
And this is a case of enthesopathy
or insertional tendinosis of the triceps tendon.
Now with nerve entrapments, the ulnar nerve can be entrapped
as it enters or extends through the cubital tunnel.
These patients present with medial elbow pain
and symptoms extending to the ring and small fingers.
The entrapment may occur at the level
of the medial epicondyle as it enters the cubital tunnel
or may occur as it exits the tunnel
and pierces the flexor pronator aponeurosis.
The ulnar nerve is seen here an ultrasound extending
through the cubital tunnel
and piercing between the flexor pronator muscles.
Here is what it looks like in short axis.
Just to give you a reference, here is the netter diagram
of the ulnar nerve as it extends along the posterior medial
elbow behind the medial epicondyle
and extending as it pierces
underneath the flexor pronator muscles on this view.
So the nerve can be enlarged greater than nine point five
is the cutoff that some people use in terms
of cross-sectional area,
but here you can see you can trace the nerve and measure it.
This is a patient who presented with medial elbow pain.
The ulnar nerve was enlarged.
Just for reference, this is the medial epicondyle
and in long axis view you can see a focal waist
or focal narrowing of that ulnar nerve.
Typically, when a nerve is pinched, the nerve proximal
to the site of entrapment will become
thickened and hypoechoic.
This is a case of cubital tunnel syndrome
or ulnar nerve entrapment.
Now patients with medial elbow pain,
one thing you may do is evaluate the ulnar nerve
for subluxation, especially if the patient is presenting
with a snapping elbow.
So just to orient you,
we are looking here in short axis at the ulnar nerve.
This is with the elbow in extension.
This is the medial epicondyle
and the ulnar nerve, which is outlined here in red.
And as they have the patient flex, we will watch
to see if the ulnar nerve subluxes anterior
to the medial epicondyle, such in this case
where you see now that the ulnar nerve
with the elbow flexion is sitting anterior
or along the medial epicondyle.
Now fluid may collect in the olecranon bursitis
and present with posterior elbow pain.
The olecranon bursa is indicated here as number nine.
It's a potential space
or a lined sac, which again can be filled with fluid.
This can sometimes be related to trauma
but can also be seen in the setting of gout.
And here are some examples of fluid distending that bursa.
You can see that it is actually a little bit overlying the triceps tendon
but also extending onto the distal portion
or more distal portions of the olecranon.
Here's a significantly distended bursa
with debris within the bursa.
One must take care when they're imaging this area
to not overly compress with the transducer as
to potentially obliterate that fluid
and miss the fluid distending that bursa.

Conclusion

And that's it for my review of common conditions that
affect the shoulder and the elbow
and their sonographic features.
And I thank you for your attention.