Ultrasonography of the Adult Hip - SD

Musculoskeletal Ultrasound: Adult Hip

Hello and welcome to the musculoskeletal ultrasound section of Sonar World. I am Dr. Tony Var from Henry Ford Hospital in midtown, Detroit, Michigan, of course, that's in the United States.

For the next half hour, I'll be talking about the adult hip and how to begin a routine exploration and try to show representative examples. And from there I hope you can use it to your advantage. And once more, welcome to the world of musculoskeletal ultra sonography.

Technique and Anatomy of the Adult Hip

For the ultra sonography of the adult hip, it would be best to begin by talking a little bit about technique and anatomy of the hip. From there, we're going to talk about the most common indications of ultra sonography of the hip.

We begin by taking a look at the most common indication, which is going to be the effusive joint, followed by some bursal lesions. And then because of the center that we're involved with and much more of orthopedic radiology, we're going to look at some traumatic cases.

Today's world definitely shows that there's a lot of joint replacement and therefore it is inevitable that we talk about ultra sonography of the prosthetic hip.

For the ultra ultrasonography of the adult hip, one has to develop the technique and have a knowledge of the anatomy of this joint. So here we see a frontal view of the normal hip. Note again that this one has the capsule over it. And once you have the collared image, try to remember that you look at images both on and on our face, face on, if you wish. We'd like to say sometimes on Foss and then a profile, as you could see on the right hand side.

So on profile, albeit that the hip is covered by the fibrous tissue of the capsule, you begin to imagine again that you have to look at images on orthogonal planes, both in gross anatomy and of course in gray scale imaging.

So let's begin by looking at the adult hip, on gray scale imaging of ultrasound in the long axis view from the femoral head to the femoral neck, let us look, from the coddle or inferior portion wherein you have the diaphysis of the femur and the tubercle of the, in this case, of course, course the lesser tuberosity as you look at the inter toteric ridge and then into the femoral neck proper.

Then at the transition between the femoral neck proper and the convexity of the femoral head, you have the subcapital line As you go cranial. Now you approach a signal void or a echo void here representing the joint space. And finally you get to see the bone acoustic landmark of the acetabulum over the acetabulum with a little bit of hypo coic highline cartilage Under cutting, you see the hyper coic triangle of the acetabular labrum continuing inferiorly.

Now you note that there is the relatively thick capsule, okay, and here you could appreciate the volume of this capsule over that you've began to begin to appreciate the multipennate structure of the idio muscle.

So while everybody is familiar with collar images of gross anatomy, we're now going to proceed in talking about the gray scale imaging Note too, that when we look at the adult hip, more often than not, we're using the curvy linear array transducer for the depth that's involved in looking at this hip joint.

And if you look at the normal hip in the long axis view, you're now familiar with the skyline pattern or the silhouette, in this profile, but it is not until you look at it also on short axis view. So you're now familiar with the hip in long axis view, and now we turn the probe in 90 degrees to look at it in its orthogonal plane.

Once you do that, you note the convexity of the femoral head and of the left hip in this case. And of course, over that you see the hyper coic triangle one more time of the acetabular labrum. On top of that, you'll see the mixed pattern and echo signature of the styre night pattern of the ilio sous muscle and idio sous tendon.

And so here, therefore one begins to appreciate the fact that all imaging must be done in orthogonal planes. It is not uncommon for us to turn slightly oblique in order to elongate the runway or the perspective of the femoral neck. As a matter of fact, when we do interventional approaches to the hip, we like this type of approach because it lengthens the runway and so our target's a bit longer.

So aside from a strict short axis view, as you can see on the right hand side, try to remember that you can also slightly oblique the transducer in order to accentuate any or all parts of the subcap portion of the hip, the normal hip, as you could see here, and a representation of the pelvis, in AP view, you could now appreciate the fact that you have to go from a level of the acetabulum into the iliac fossa.

This is important because of the proximity and continuity of the hip into the iliac fossa case in point, for example, everybody knows that the ilio sous bursa can itself ascend into the ipsilateral iliac fossa.

So here in gray scale imaging, you can appreciate the bone acoustic landmark of the inner portion of the iliac or innominate bone. And as you could now notice that at the level of the higher portion of the iliac bowl, you now see the hypo coic sous muscle or iliac is in this case. And of course, the musculo tendonous junction of the ilio sous proper of the left hip and pelvis us.

So if you have familiarize yourself with the anatomy of the hip, it's now time to look at some of the uses of hip ultrasound in the in your patient.

Indications for Hip Ultrasonography

Hip Effusion

Let's begin again by looking at something in, long axis view, and that means it's gonna be in profile for the hip, of course, most commonly. And all of us have rehearsed, how to look at the effusive hip joint in the anterior approach only.

So the collection of fluid, will definitely be shown as it distain the capsule. As you can see here, a schematic drawing superimposed, on a black and white image of the colored images I showed you earlier. But please do not forget, that fluid loves to gravitate and therefore it could pull into the posterior inferior portion as shown here by the number two.

So you must position the patient in such a way that after you've addressed the anterior portion or the anterior capsule that you'd like to check the posterior region in doing so, when you look for hip effusion, a left, left right comparison is important.

Case in point, for example, we already have seen in the normal left hip in the normal anatomy we just addressed, and everybody remembers the silhouette of the acetabulum acetabular labrum, convexity of the femoral head, the subcapital neck part, in the proper neck portion of the front femur, and finally into the interrater region. And of course, the non distended capsule adjacent to the ilio sous muscle in the affected hip.

Immediately over the acetabulum, femur and femoral neck, you'll notice a distended capsule and within its, mixed echogenic pattern representing an effusion. So left right comparison is essential, especially when you address it to the non imagers like you're referring physicians or emergency room physicians.

So once, you are familiar with distension of the capsule, we can now begin to show some cases. This, elderly, gentleman comes in with pain and fever and you do not even have to address, or even hint at which hip is going to be affected. Point is you're gonna do a left right comparison, but first let's look at the radiographs.

As you could see, of course, there already is joint space narrowing of the right hip. Let's go back to the initial examination or radiograph and recall that there is a great difference between the degree of the joint space on the asymptomatic left and the affected, right? So here you see a dedicated view of the right hip confirming indeed that there is joint space narrowing.

And you could even get a hint that there is a little bit of distension of the gluteal outline and the ilio sous outline on this cone down view of the radiograph. It's not uncommon to immediately ask for an MRI if it's an emergent type of in of reason.

And here you could see on a proton density coronal image that there is some signal void in the subc chondral region representing fluid or contusion. Again, you could appreciate probably less than the radiograph, but still to some degree the joint space narrowing on mr. And of course, once you use these fluid sensitive, T two sequence, obviously now you begin to appreciate not only the subc chondral edema we talked about of the femoral head, but also that affecting the acetabular region, plus the distension of the capsule by fluid.

Probably very little, much less appreciated on the proton density, coronal images of course, immediately if you were to plant a probe in this individual right off the bat, you could see in the long axis view here the silhouette of the acid tablum and the femur. The, the standard capsule and focal to it would be some neovascular and a Doppler positive hip, meaning that there is some indeed inflammation occurring in this individuals, this is the right hip.

So now we're going to rotate the probe counterclockwise and we're going to look at a plane at the level of the femoral neck. And when you do that, that you appreciate it on the long axis view, note that on the short axis view the markedly dete capsule in the sub femoral region, confirmation of the effusive hip in this at this point, very simply, therefore still in the short axis view at the right hip, you can introduce a needle as shown here by this high level linear echo.

And to accentuate that, it is not uncommon for us to apply power doppler in order to see not only the extent, but also the the direction of the needle. So with power doppler, therefore it helps us, to immediately visualize the needle and not only the shaft of the needle, but the very tip of the bevel in order to be clearly positive that we're within sampling area of the hip.

This is a video clip available on the Eular website, and this is, Dr. Johan Koski from Finland. And this is the approach that most of us will take. Note that he will park the probe more or less in a compromised long axi short axis view to get a longer runway of the femoral neck, and that he likes to visualize the shaft of the needle in the long axis view, which is the same way we practice in our institution here on the gray scale imaging in real time.

Notice that the needle is introduced and as it approaches the capsule, you jab it in and then you get to see the very tip and bevel of the needle in this distended, hip joint. Okay? So this is a very easy approach and to date, therefore, we never try to stick a joint blindly. We always almost use ultrasound guided approaches, in this individual's in HIPA fusion.

Like we told you earlier, that a left right comparison is necessary. And here, case in point, for example, on the abnormal side, you'll see a distended capsule while on the unaffected opposite side you notice that it's still down sloping and uninvolved. But as you look at the distended capture a little bit more closely as you make a left right sweep or as you pan or zigzag through the hip joint, you'll notice that inside the capsule there are some punctate high level echos.

These high level echos, eventually on radiographs are confirmed to be radio densities, on this frog leg radiograph. And on a coronal image, proton density, you will see that there is indeed a distention of the capsule by uncomplicated fluid on the actual images at the level of the femoral neck. You'll notice not only that the standard capsule, but also some synovitis involved.

But yet as you look a little bit closer on the T two image here, on a actual, you'll notice this signal voids representing synovial chondro mitosis. So it is important after you have looked at the fluid in any effusion, especially in the hip, to further characterize it, if there is going to be some high-level punctate echoes in this case representing the innumerable loose bodies of synovial chondro mitosis versus synovitis,

let's now look at another case where the individual comes in with hip pain and effusion. One more time until we identify an ultrasound or sometimes on radiographs, we probably wouldn't guess right away which hip is involved, but once we ask the patient, to continue with another frontal view, cone down view, accompanied by a frog leg lateral view, we appreciate that.

In the translation from the AP view to the frog leg lateral view, there's a persistent, radiopaque density at the lateral aspect of the subcap joint. And this loose body now is readily confirmed in the long axis view and ultrasound. When you see that between the bone acoustic landmark of the acetabulum and the convexity of the femoral head, you see the scurvy linear high level echo in between the two structures plus dis descending the capsule confirming indeed that this is a loose body on a, on a more superficial scan, again, confirmation indeed that it is between the acetate in femoral head dis stand in the capsule of this loose body within the hip joint.

So not only can we see synovial condom mitosis with innumerable high level loose bodies, high level echo loose bodies, but also a single loose body in people with a loose body in the hip joint. Of course, if you do a left right comparison, you begin to appreciate this immediately. Case in point, for example, we already saw that in long axis U, we saw this high level covering your echo in the extended capsule of the right hip, and immediately when you show it on the left hand side, you begin to see the great difference between the two readily convincing a novice or non imager that indeed it's a unilateral loose body in this hip in another patient.

As we look at sequential planes of a T two choal image of the hip, you'll notice that at the plane of the sacrum or sacro iliac joint, as we proceed from posterior cutting into the anterior portion, we now get to see that there's asymmetry between the two hip joints. And probably best appreciated to us probably the last two sections here wherein you could see that there is a collection of abnormal intensity and signal aberration on the right hip.

If you look at that, therefore you are approaching your visually the right posterior hip. In this individual, we could readily detect the bone acoustic landmark of the posterior acetabulum and an abnormal collection of mixed tissue, right posterior or immediately posterior to it.

So on ultrasound, therefore this is what you're going to see. But first, since we already oriented you on MRI, let's again start with that already, we were pointing out that there is increased signal aberration, asymmetrically affecting the right hip here, for example, the same fluid collection that you can appreciate and see on MRI is readily seen on the same choal view on ultrasound.

And this is the posterior approach. This is why, although anterior approach is probably easier, do not forget to look at the posterior hip. And here you begin to note that there is a hypoechoic collection of fluids surrounded by a rind of soft tissue representing this abnormality on a, if you wish, a long axis view, and then on a short axis view, again, giving you that orthogonal orientation and triangulation that you'll need as an imager.

Once you've identified that, we'll stay on the axial view, and again, you have your target, listed here and visualize as hypo coic lesion. All you need to do now is introduce a needle, and very clearly you could see the entire shaft of the needle, but not only that, but also there's a bevel in the tip of the needle to the point that you can even see that it is a bevel up, that the bevel is directed superiorly, or at least in this case anteriorly, in order to sample correctly this posterior hip effusion in this individual.

Of course, the most common bug that we've been cultivating in our center is going to be staphylococcus orus. So ultrasound not only confirmed that there is abnormal effusion, but also helped us direct the needle exactly to the sampling that we needed.

Bursal Lesions

Let's move on to the multiple bur se of the hip. And this is going to be important. The definition of a bursa is a small purse or bag in Latin and wine skin or hide, but animal hide In Greek, there are more than the three burs, that we're going to talk about the hip. But let's concentrate on the ilio. So IC bursa and the gluteal bursa In schematic drawing, we're going to show first, the more common greater trocanter bursa on the lateral aspect, usually draped over the greater trocanter.

And then the least common is going to be the iscu gluteal bursa located, just over the posterior cubicle of the isum. And, the drastically more common I just oas bursa sometimes confused, as an abscess. But also remember that this one likes to ascend into the iliac fossa is going to be the ilio sous bursa in a sagal view of this, or sorry, excuse me, on the axi view, or you could appreciate the ilia. So bursa jotting out of the femoral head in between the Ilia sous and the continuous, but, but remember that it's clearly adjacent to the great vessels.

So this same bursa would like to ascend into the iliac fossa on the corona coronal view the ia. So bursa again, it starts at the Ilia, so junction and insertion on the lesser trocanter, and it likes to occur in between them. But notice that it's going to go over the i canal ligament and deposit itself over the iliac fossa.

Suffice to say therefore that it is, on the medial aspect of the hip and within the proximity of the great vessels here on the left hip of a patient, on a T two actual view of the hip, you'll notice the femoral head and then the acetabular fossa here on the anterior pillar of the acetabulum against the femoral head is a distended collection of signal aberration that represents the bursa.

Note that it is in the proximity, not only of the great vessels, but also of the ilio tendon. This pulse style mass that was, present for a whole month is seen an ultrasound as a hypo coic lesion. However, notice that you can't tell what's going to be the bursitis or cyst if you wish, against what is going to be great vessels with ultrasound.

One of the great advantages that you have doppler in this case, of course, color doppler angiography confirms that the upper portion of the hypo hypoechoic abnormality were the great vessels and the lower portion was the bursa.

This is a case that presented to us by Dr. Keho Cho from Daegu, South Korea. Now, if we take a look, at, this bursitis, notice how it likes to elevate itself out of the joint into the iliac fossa. Likewise, the size of these, bursitis can be pretty monumental.

So one more time in the long axis view, you can identify immediately, the femoral head against the acetabulum. And initially when you put your probe down, you'll notice that it's very difficult to delineate what's going to be the sac or bursitis, the cystic, appearance against what's gonna be great vessels.

Many of us, of course, are very familiar with the pulsitile nature of the great vessels and probably can appreciate it in great scale, but it's not until you put a doppler angiography that definitely now you could see that it is the great vessel that is draped over this large and monumental SOAs bursitis.

Sometimes they will be quite small and yet approachable by needle guidance. Case in point, in this example, on the right, on the right, hip of the patient who's lying down and you're looking at the patient from from his feet, you'll notice that there's a heart shape collection of increased abnormal signal collection should be representing fluid.

Note that it's push the tendon to the lateral aspect on short axis view and on actual view, these are the great vessels. Also, before you leave the Mr image and look at the ultrasound image, note that if you jump from the right hip to the left hip, there's a smaller ilio sous bursa. Again, one more time immediately adjacent to the tendon idio sous tendon and in proximity of the great vessels, looking at, the right hip on ultrasound and short axis view,

you can readily identify the bone acoustic landmark of the acetabulum in femoral head, but also the bristle pattern of the tendon. And then once you have identified that there is a collection of hypo echogenicity in between the tendon and a second area of hypoechoic structures, clearly if you've done that, then remember that it was going to be tendon versa and vessels.

So an ultrasound on non short axis view. Now, one more time, Bon Christie, landmark of the femoral head. On top of that is the tendon of the ilio sous and put doppler in because immediately you confirm that what was signal void on Mr and initially echo loosened. Now clearly were the great vessels, but what's important about this case now is you could appreciate the fact that we have clearly demarcated all the structures, therefore we can now thread a needle exactly to the area that we need to sample.

So once you have that, you can direct under ultrasound guidance not only the direction of the shaft of the needle, but also the very tip or bevel of the needle. And in this case, it only turned out to be hydroxy appetite induced synovitis in a patient who had prostate carcinoma. But again, one more time, sampling it under ultrasound guide and clearly gives us that after aspiration we have a clear diagnosis in this case, hydroxy appetite synovitis let's, switch, from the more common idio bursitis to the greater trocanter bursa.

And if you take a look at this schematic drawing, you'll notice, that all segments of the gluteus muscle from the minimus, to the maxima have interdigitating bursa. And what is interesting about this is that each one has its own insertion, or at least each muscle group has its own insertion into the facet of the greater trocanter.

But even more interesting than that is that between every muscle group of the gluteus, you'll notice some bursa. Of course, while we call it bursitis, it's very difficult to separate what is bursitis from tendonitis. That's a schematic drawing here. One more time, one line drawing showing clearly that the minimus medias in the fascia ladder or g gluteus maximus, which inserts on the fascia lata have each individual bursa.

And again, for confirmation, you can go ahead and inject some barium contrast. Here you see on a, c arm image or radiography that we can inject each bursa individually and confirming the location here. Of course, as you can see from Dunn's clinical anatomy in 2003, that we can feel this potential spaces with contrast.

On c-arm imaging, it is easy to confirm the silhouette on long axis view of the greater trocanter. And so here, for example, on the right hip, you can identify the greater trocanter and then the subtrochanteric region going into the method thees of the femur over that you have not only the the iliotibial band, but also insertion of the al muscles.

This is on the long axis view. So a patient in the cubitus position very simply line up the transducer, identify the silhouette of not only the greater tro canor, but also a part of the lateral acetabulum or if you wish the ileum. Once you've done that, with a little bit of heel toe maneuver, you can confirm the fibrillary pattern inserting into the enthesis of the greater ter canor when affected.

Immediately of course you know that over the greater trocanter you're going to see a distended, fluid field sac, most likely, usually uncomplicated, but in chronic cases, of course you'll see some intraluminal echoes within this distended sac.

Let's begin by taking a, short axis view of, coronal, sorry, of actual uh, MRI image in T two. And the fluid sensitive sequence tells you that around the greater trocanter, here's the fal head, fal neck, greater trocanter. On the medial aspect, you see the acetabular fossa that around the greater trocanter you have a collection of, of abnormal fluid, distending not only from the anterior portion all the way down, all the way posteriorly to the back of the patient's hip, very easily park your transducer.

Then you see the bone acoustic landmark of the de greater tr canor and of course surrounding it you see this dete bursa around the individual note, that you have to again look entirely all the way down, all the way back of the hip in order to confirm the extent of this disease.

Now we're going to turn the probe around, from the short axis view, rotate your probe counter-clockwise to look at it on long axis view. And in doing so immediately you have already rehearsed on how to look at the long axis view of the greater tro canner, and you see the tubercle and at the meta theis of the femur and what was supposed to be an imperceptible bursa and uninterrupted ular insertion into the greater trocanter.

Now you see this markedly distended sac confirmation of a trochanteric bursitis in a 50-year-old female on short axis view ultrasound long axis view ultrasound for confirmation. Of course, you may employ Mr, but it really was unnecessary.

The least most common, bursa in the hip is the going to be the one over the isum of, the iki tuberosity or the tubercle of the ischial tuberosity. It is said that it's usually secondary to sitting on higher surfaces while crossing their legs. So quite common in some, Asian cultures wherein people like to squat more often than not here from, movers anatomy, you could see that the pressure that's going to be demanded on the isal tuberosity as people have prolonged sitting, for example, in a chair or if they were to squat for lengthy periods of time.

And so these could be seen in vibration related jobs such as cloth weavers, tractor drivers, or those semi drivers and of course road equipment, machines that really have sustained vibration of their equipment. Once in a while, of course, you'll notice, that what is ever in industrial medicine is translated into the athletes, and we see this in canoeing and horseback riding.

What we see in these individuals is a referred pain around the ischial tuberosity from the iki bursitis. And why not here while netter's drawing shows a left hip examination? And if we do a gross anatomy, look at it, you'll appreciate the fact that if you take a peak at the ischial tuberosity, that the proximity of, the sciatic nerve to this area and the posterior cutaneous nerves to this tubercle and a potential and a very potential bursa is, really most likely to affect all these structures.

So on MR Imaging, if you look at the left hip of an individual, let's begin by taking a peek on the fluid sensitive T two image. You'll notice that the unaffected isq tuberosity on the right side as we go over the patient's perineum onto the left side, that clearly there is a signal aberration unilateral to the left side.

And as we jump to the actual imaging, patient is lying down and you're looking at the patient from his or her feet, you'll notice, the left right comparison. There's a collection of fluid. But again, if you take a sagittal view of the same individual, here's the ischial tuberosity and this is the anterior portion of the patient, you'll notice that there's a fluid blood or fluid fluid level.

And of course, isn't it much more simple to look at it on ultrasound? Because if you do this in the long axis view, that means the top of your transducer is directed to patient's head and the bottom of your transducer patient's feet. Not only do you confirm a distension of the bursa, but also a fluid, fluid level, but clearly the higher level echoes that you could see is the particulate, portions of blood that is gravitating to that area.

Traumatic Cases

So we've seen technique, anatomy, effusion and bursitis. And now let's jump into what trauma would appear like in chronic disease, or AULs injuries. So this is what could appear. Let's first look at the asymptomatic side. On the right hand side, you see the anterior inferior iliac spine where the origin of the rectus fem is.

And if you jump to the affected side, you'll clearly note that there is asymmetry or a lot more traffic on the affected side. So what was supposed to be a sustained fibrile pattern of the tendon is now interrupted by this hypo coic collection of fluid.

Let's go to the short axis view first the unaffected side. And you can see the bristle pattern of the hyper coic tendon clearly inserting into the anterior inferior iliac spine. The affected side has not only this hypo echogenicity, but a rind of high level echoes surrounding it without too much of a posterior acoustic shadowing.

So when you do a doppler positivity on this individual, you could see that not only does it confirm the extent of the disease, but also the acuity or recurrence of this disease.

So in this same individual, therefore, if you were to take a radiograph, a frontal radiograph in this case cone down or cropped, you'll appreciate now a high level opacity adjacent to the anterior inferior iliac spine, indeed confirming that there is an abnormality in that region for academic sake.

Although it's so clearly unnecessary, let's look at the corresponding coronal view. And you'll notice that on the fluid sensitive T two sequence that there is increased fluid collection trickling down, but also a signal void surrounding the same rain that represented the calcification.

If you look at this on actual MR images, very difficult to immediately detect the abnormality on the anatomic sequence. Here you see the femoral head, the acetabulum, the anterior field IAC spine. It is not until you employ the actual image on T two sequence for the fluid sensitivity that you begin to appreciate the edema, the abnormal fluid collection, and of course the signal void representing the calcifications in front of the hip at the origin of the anterior inferior iliac spine.

Once in a while you'll be directed into some symptomology of the ad doctors or some people might think about bulia. So, so pain in the pubic synthesis area is also addressed as part of the hip exploration. Here you could see, the gross anatomy of the different facets and tubercle of the lateral portion of the synthesis pubis, where you're going to see the origin of the ad doctor longus, brevis and Magnus.

As you go from the cranial portion, as you go from the inferior portion to the cranial portion, you'll notice each individual facets and insertions of the aduc. What is going to be important here initially, for the imagers who want to begin an exploration of hip studies is to do a left right comparison.

So for adductor tears, for example, when you begin initially, you'll notice that the aduc longus, brevis and Magnus, and if you look at the bone acoustic landmark, you could see that there may be some interruption and edema or contusion of the longus at this point, but it's not until you do a long axis short axis view that you'll see that there's indeed an interruption of the penate structure of the muscles in this case.

Here you see the hypo coic defect, a measurable gap in this individual now consisting indeed of an a de duct tear and from a short axis view. Now you take a look at a long axis view. Now you can clearly see not only the retraction of the medial and lateral stumps, but also a large collection of hematoma inter interposed within this area.

I know that, it's easy for us to judge people who like work in emergency rooms or at least for walk-in patients. And it may be quite difficult to, but once in a while, be it as it may, we on radiographs may miss some, some fractures. Case in point, a 65-year-old female comes in with dull pain in the left hip for the past, two weeks.

While initially the radiographs were dictated as unremarkable, but it is the radiographically occult fractures that may occur. And sure enough, because it is hip pain, you know, they might ask for an ultrasound to look for an effusive hip.

Let's begin with the unaffected right side. And you already are familiar with bone acoustic gland, mark of femoral head, the subcapital region and the femoral neck. You note here that the capsule is not distended and that the iose muscle is not splayed.

If you look at the affected side, immediately you'll see a step off deformity on ultrasound representing what should be a capsule or a spur. And if you ask for new radiographs, you'll see the sclerotic band in the subcapital region representing an undisplaced insufficiency fracture.

For a confirmation in invi an individual who already had an initial occult radiograph, you might need an Mr. So fight to say though that we already appreciated it and saw it on ultrasound. So here on a coronal uh, proton density or T one image, you see a signal void, linear signal abnormality across the subcapital region on the left hip, very different from the contralateral right hip.

Jumping from there now and asking for a fluid sensitive sequence, not only do you see the bone marrow edema in contusion in this individual, but also the same signal void that you appreciated on T one cutting across the subcapital region. But all corresponding to already the sono graphically evident undisplaced subcapital fracture of the left hip.

And as you can tell, this individual with this subcapital fracture needed three cannulated screws in order to have internal fixation or percutaneous fixation of this hip. So confirmation indeed that not only visually but also clinically, this was a hip fracture.

It's interesting, that you know, we've seen the bone acoustic landmarks in this individual, the joint space or the joint line, and not only do we see them, but also the acid tabular labrum. So if you look at on long axis and chart axis view, you can identify the fal heads and the acetabulum in between them. You see this hyper coic triangle both on long axis and chart axis off the acetabular labrum.

This is going to be important nowadays because of the femoral ace tabular impingement. So if you put your probe in, let's say the long axis view, you may see first on the unaffected side, the bone acoustic landmarks of the ace tablum and femur and a preserved triangle of the labrum. But as you jump towards the affected side, you see the bone acoustic landmark of the acetabulum and femoral head, but instead of the expected hyper coic triangle of a labrum, now you see a disruption and a perla cyst occurring to this clearly.

Now showing acetabular labral tears.

Prosthetic Hip

Let us end the discussion of the ultra sonography adult hip by looking at the prosthetic joint. Here you have a patient coming in with a painful unilateral left prosthesis on radiographs, very difficult to appreciate going on probably except maybe an elevated cal car. But again, an ultrasound. We're going to look first for abnormal fluid, not only in the proximal portion of it, but also on the distal portions.

So we're going to look at the fluid and the integrity of the pseudo capsular in in this individuals. What we'd like to do is to look at it on long axis and we are going to look at the prosthesis versus the native bone because if there's any abnormality it's going to be between the prosthesis and the native bone.

So clearly, while this is very tempting to sample between the prosthetic femoral head, femoral neck, you'll notice that maybe this is the region that we do have to address. We do like to address that because here the probe is on long axis view. Note that you'll see the metallic prosthesis.

So any abnormal collection of fluid dis extending the pseudo capsule at the inter toteric ridge at the interrater ridge at the inter toteric ridge is the area that we're going to take a p at. So case in point, therefore, when an individual or 50-year-old young-ish male comes in with painful prosthesis, only five years after a ceramic total hip replacement, we're going to address not only the metallic portions but also the inter toteric ridge.

We're going to look for not only septic loosening, but also mechanical and mechanical loosening and where debris synovitis. We do this one more time by looking at it in the long axis view and you see the reverberation artifact, of the acid tab, but much more so with the fal neck.

And like I said, while you say that this capsule may be distended, it is over the native bone that we need to look at it clearly. Here you see that there is a greater than four millimeter or five millimeter distension of that capsule, probably better appreciated in a profile and a cross table lateral view in this individual.

So here's the ace tablum and then the metallic head and metallic neck. So you could see there were variation artifacts of the femoral head, femoral neck. So it is this region that is of concern to us and that's the site where most of us would sample and then that individual of course would be abnormal. And of course we need some sampling.

Usually it might be infected in the inflammatory and infections of, the prosthesis and hardware. We try to look for abnormal fluids surrounding the hardware. As you could see here, very difficult to appreciate of course on the radiographs, but on ultrasound clearly you get to see the high level echoes with reverberation artifact of the prosthesis and abnormal fluid co collecting over it.

So here you see dynamic imaging we're in. Now you started on long axis and on short axis you begin to see the prosthesis and the abnormal fluid collecting over it. But maybe some of you have already appreciated some punctate high level echoes on the left hand side of the prosthesis.

We don't know if this is gas and trapped in the synovitis or maybe some debris floating. Notice later on that while they're percolating on the dependent side, you can aspirate this same bubbles and confirmation what's going on. Here you see a tip of a needle. That was a high level echo. Employing one more time Doppler, we accentuate the tip of the needle.

Sometimes it may be in color, but definitely it's high echo at this point. Notice that the bubbles that I mentioned are percolating on the inside part and you could suck the samples from the dependent portion to the bevel of the needle itself. Confirmation indeed that this was positive. And usually for staphylococcus ous infection, the sample that we get, would be again, purulent.

And the different, parameters that we need are definitely a gram stain cell count and culture, especially if the patient has not started his antibiotics. In addition though, however, we'd like to, centrifuge much of this and to look at it on polarized microscopy for any, crystalline arthropathy in this individual's for bacterial infections.

As you could see in this prosthesis with chronic osteomyelitis and already a failed portion of it, notice that if you were to introduce contrast in the intracapsular portion of the acetabular femoral joint, some of it would trickle inferiorly into the distal portion. Therefore, it'll behoove you to make sure that not only do you check the hip portion, but also the distal parts case in point in this individual once, you could see that indeed you see the prosthesis and abnormal collection of fluid.

So anytime we see extracapsular, extra articular, but peri focal fluid collection along the prosthesis, that for us represents bacterial infection. Here you can note that a more difficult sampling of the hip is readily sampled in the distal portion on short axis and on long axis already you could see that while the callous formation might be buttressing enough, there may be an elevated portion, but at this abnormal fluid collection that we would target for extra articular collections.

So another one here with a dynamic hip screw modified to take in another compression screw and multiple failed screws around it, isn't it much simpler Instead of sampling the hip, as you could see with a pseudo capsule to go down to the distal portion, again, the high level echoes of the prosthesis, but the abnormal collection of fluid clearly states that this is what you need to sample.

So once you go from the hip all the way down to the plate, as you could see here without any reation artifact, but as you proceed further coddly inferiorly, that abnormal collection of fluid tells you that indeed this is the area that you wanna sample for confirmation.

Once in a while though, you could have changes like this. Note the incongruity of the art artificial femoral head against the acetabular cup. We don't know if this was a traumatic dislocation or simply wear and tear an ultrasound in the long axis view. You can identify the intra anterior cre, the pseudo capsule, the reverberation of the femoral neck and femoral head.

But lo and behold, while you may think that this is part of the acetabular component, when we do a dynamic imaging notice that it releases and you know that this is an artifact and intraluminal collection. So when you do a neutral and compression neutral and compression, you notice that this artificial intraluminal debris is too much to bear.

And therefore we confirmed indeed that this is a loose plastic. Here you could see that laminal structure already appreciated and seen on the ultrasound. So this was not really like a dislocation, but simply wear in tear of the polyethylene lining, polyethylene lining of the failed prosthesis in this case.

And again, in vitro confirming one more time what we were seeing in vivo in this individual's the painful postoperative hip and somebody with core decompression or screws removed or fibular if you wish. Graphs in this individuals are very helpful here on mr. You could see the retained tracks in this individual surrounding fluid around the area, but it's readily more probably seen that we could look at this, changes in this individual with a kidney transplant around the region.

So kidney transplant, fibular grafting, avascular necrosis, what is going on with the right hip. Now the artifacts laden MRI images is very difficult to see, but once it developed fever and pain, we could again, again have a baseline radiograph go into the more complicated or very complex interpretation of mr. But very simply for us, because we don't have an open magnet yet again, immediate confirmation of the fluid collection between the acetabulum and femur and a distension note that it is a failed graft because of the fluid accumulating outside it and therefore very simply for us to sample the region.

And if it's sterile, we know that maybe it is disengaging in some of the graph material outside of the femoral neck versus culture if there's going to be positive changes. In this case, it turned out to be gram-positive cocci. So very nice perspective and orientation on MR confirmation and ultrasound and definitely sampling by ultrasound.

Again, the patient needed a post-operative as you could see changes here in this individual. And of course he went on to have a hip replacement later on. Once in a while we encounter cases like this wherein we're sure that the pain is secondary to this prosthesis. We'll warn you while it's very easy to approach the hip portion, the intraarticular portion, that it's not uncommon that something else is gonna occur extra articular or distally.

So what are we looking here? We're looking at a failed prosthesis. Are we're looking at a secondary tumor effect changes in this individual like a sarcoma or is it simply loosening? So we begin to look first at the baseline. Radiographs cone down views, shows you that the very end of the tip of the prosthesis, you have this cauliflower frightening appearance speculated lesion, and that's what we're going to address.

Therefore, it's unnecessary to go to the acetabular portion on ultrasound. Again, the horn leg cauliflower type of appearance is persists. But even more interesting is the fluid collection in this individual. And again, perforating the cortex alte femur.

First on ct, the low attenuation corresponds to the echo lucent abnormality. Here you see the horns of the cortical remodeling that we already appreciated on the radiographs. And one more time on ultrasound, but again, re demonstrated on ct. But also on ct you could see inside more high level attenuation that could represent some debris.

Not to forget that we'd like to use Mr and Mr. You'll see there's a fluid collection, but again, you have extraneous material occurring well within this inter luminal portion. What was important about all the additive, modalities we had to the baseline radiograph is that we're showing that there's no soft tissue extension, that indeed the source was coming from the intermediary portion of, the femur, presumably from the indwelling prosthesis.

So here we already saw it on ultrasound on short axis view, and now let's look at it on real time imaging. On real time imaging. You can now see that there is the continued cortical shield of the femur, but as we go proceed further down, now we're going to see the abnormal collection of fluid in this individual's.

So we're still looking at infection versus inflammation and as you could tell now as we switch there, is this needle coming in? Notice that the bevel is down and that we are approaching just the fluid, but then we could sample whatever areas we need here, a little bit of possibly air introduced by us or maybe part of debris that we were sampling.

Case in point though, we're telling you that, you know, we're going to sample it easily with ultrasound and going around, we scoot and sample not only the fluid, but also some of the soft tissues. When we do that, what we collect are this, flake like, I guess whiteish substances that look like a pseudo abscess to us.

But yet when you do histologies in these individuals, you'll notice that this collection against, the backdrop of some leukocytes definitely tells you that this is particle disease. So what happens? The failed prosthesis was trickling down and exuding towards the distal portion and, the prosthesis itself completely failed.

And here, if you wish, you see this tumor effect changes representing an implant where that was seen on ultrasound as a collection of fluid clearly sampled immediately on ultrasound, under needle guidance and on Mr. Telling us the different intensities present. But it's not until we see it and sample with ultrasound that we confirm that this is particle disease mimicking a tumor.

Conclusion

So in conclusion, therefore get to know the technique and the anatomy of the hip in order to have an easy time and facilitating the exploration of the hip and the different indications of effusion, bursitis, trauma and prosthesis you're now familiar with. And so with that, therefore I think, one should be able to do a good ultrasound examination of the adult hip.

Thank you so much for your attention and I had a great time being with you today.