All right, good morning, everybody, happy Friday. Thanks for joining us this week for our every other week AMSSM Sports Ultrasound Case Series. So today, we're fortunate to have Pierre Demacor here to present a case to us. Just a quick bit of background on Pierre. He's originally emergency medicine trained. He did his sports medicine fellowship out at Boston Children's, which is where he currently is. He serves the role as the sports ultrasound director out there. And he is, I guess, a sports medicine physician out in Boston. So Pierre is actually going to be talking about a particular case of a hip labrum tear in a patient with some borderline hip dysplasia as well, which I think is going to be quite interesting. So with that, I will give it over to Pierre. Great, thank you very much. Thanks for the opportunity to talk. It's really a favorite topic of mine. Let me get to my slides here. So I already hit share screen. I don't see my slides. Yeah, I'm not seeing them yet. OK, great. There they are. Can you see everything in there? We cannot. Do you want me to go back on? I'll try again if I stop and then re-share. Do you see that? Yep, there we go. Got it. OK. OK, great. So I have no disclosures. And I wanted to say a special thanks to the hip team that's been working on this for a long time. And I want to say a special thank you to all of the staff that's been working on this. I have no disclosures. And I wanted to say a special thanks to the hip team at Boston Children's. There's sort of a multidisciplinary group that's been meeting for almost 10 years now on Thursday mornings and discussing and collaborating on cases. And even with some outside the hospital surgeons as well come in to participate. Mike Millis, who started the hip preservation program at Children's, really got this whole idea going. And so there's the open hip surgeons, the ones that do the PAOs. There's the arthroscopic surgeons. There's all my ultrasound partners who are working with it and physical therapists. And then we have a lot of the athletic trainers that help work with us. So it's a pretty neat group. And so these are some of the things that we have been doing. And I'll go through it. My objectives are basically to review some of that pertinent anatomy and to discuss some of the other imaging and the complementary imaging to ultrasound and review a case, of course, of someone with anterior hip pain and use this case to basically go through the protocol for the anterior hip examination by AIUM. And then we'll discuss the utility in different circumstances for using the dynamic exam. And we'll have sort of newer dynamic exams that may or may not be helpful. And then review the report. So just going through some of the anatomy, what you want to do with some of the bony things, because the bony things are the things that you can recognize right away and they jump right out at you at your home base. And so knowing the anterior superior iliac spine where the sartorius attaches and very particularly where the rectus attaches, which is, as you can see, is right above the femoral head right here and can actually cause a subspine impingement itself and is where the rectus can get into trouble from time to time. And then you've got the iliopectomial line where the psoas has to go over and can be an issue. But it's a good home base to sort of look at the psoas when you're there. And then the lesser trochanter is important because, of course, the psoas goes down there and you have to recognize that the psoas really has to make this really arduous course. It comes all the way down from the T12 and joins the iliacus and then inserts posteriorly so it actually flexes and externally rotates the hip. Then the acetabulum, of course, has the gasket, which is the labrum, and that helps seal and keep the tight seal there. Then there's the capsule. And then I think for people that are interested in any of the micro instability, which I am, there's the iliofemoral ligament, which is a large Y-shaped ligament where the anterior fibers are very vertical. The posterior fibers are more horizontal, but it really gives you a lot of interolateral stability to the hip. And perhaps some of the people with Ehlers-Danlos and people that are subluxing a lot need work with that. And there are certain regenerative techniques that sometimes can be used for that. Then you have the rectus femoris, which comes up. This isn't the greatest anatomic specimen, but basically what happens is you have the direct head here and then you have the reflected head. And that's the important one to remember because we see that get into trouble a lot, particularly when you start moving bones around with the PAO. I've seen a bunch of reflected head problems with people that have had total hip arthroplasty getting a lot of pain and calcification right in that area there. And looking at it, it's not the easiest thing in the world, as we'll try to demonstrate in a few minutes. So that's the reflected head that you want to keep an eye on. And then the other thing is, of course, the iliopsoas. And so you've got this large, triangular iliacus muscle that comes down and joins with the psoas to, again, insert right where the lesser trochanter is. And the pectineus is just outside of it. Predominantly, when you're doing the anterior exam, you're sort of examining it in a fairly small window right here between the rectus and the psoas muscle right in that area there. So when you have hip pain, I think one of the first things that I try to categorize the patient into is, is this a hip pain patient or is this a hip preservation patient? And I think that you can get an MRI and it really won't tell you what the story is. I think what I want to always see very first is a good standing AP pelvis. And it has to be standing, in my mind, because if it's a supine film, you may not have that same weight bearing that may pull a little bit more out on the ephemeral head so that you get a little bit more dysplastic types of changes. So when I'm thinking dysplasia, I always want to make sure that I get a standing AP. And then I'll usually get a false profile view. And then we get the done view. And I'm not sure you always have to get all of those. But if I'm going to get an x-ray, I always get a standing AP. And then it sort of depends on how the patient's doing. I may add the other ones in. But those are the three x-rays that will tell me a lot about whether it's a hip preservation patient or not and fairly easy to get. So in that light, I wanted to just bring out the point that the lateral center edge angle, it's important that that's above 25. So there's some controversy in the literature. But if you have a lateral center edge angle greater than 25, that's normal. 20 to 25 is in that sort of borderline zone. Some people say down to 18. And then below 20, it starts to get more serious. And Murphy did a study that showed that if you have it less than 16, you have a more less than 16, you have basically 100% chance of having osteoarthritis by the age of 60. And then the anterior center edge angle from the false profile view should be about 20. So this is a young man, 18-year-old college freshman with a two-year history of anterior hip pain. And mostly came out of running. He's not a huge runner, but he runs recreational. He's not specifically an athlete. No trouble sleeping. Otherwise, his past medical history was negative. But his mother, who's a pediatrician in our community, I had diagnosed with dysplasia. It was a borderline dysplasia, but it was pretty significant. And she ended up getting a PAO four months ago. And then about two months ago, she brought her daughter to me who also has dysplasia and more significant dysplasia. So the differential diagnosis was narrowing very quickly. And so on physical findings, he had a positive fader, but he also had a positive apprehension test, which is when you extend, adduct, and externally rotate. And if that causes anterior pain, that's more consistent with instability. It causes posterior pain, and it's posterior impingement many times. The only other thing I bring up is that he had a big crossover in his gait. So he brought me a little video of his running. From a rear view, he had a crossover, which was probably additive to that as well. He, at school, he had had an MRI that showed a labral tear, but there was no x-rays done at all. So when I saw him, I got some x-rays. And as you can see here, not bad. He's got a lateral center range angle of 21 and an anterior center range angle of 15. So fairly unstable. And he was getting some delamination on the MRI right at the chondrolabral juncture, sort of indicating that maybe he was pushing a little hard on that anterior portion because of the uncoverage. So now we decided to do an ultrasound, of course. And so I'm going to go through the basic protocol. And most of the people that I see doing this really start with the femoral head, neck, acetabulum, long axis, and then short axis, and then move to tendons around that area. I typically start at the rectus. And it's just my own thing. I think Marnix taught me that many years ago. And then I move more medially into the femoral head, neck, and then to the psoas, et cetera. But anyway, so you want to kind of get a good idea of the femoral head, neck, and then look at the rectus, psoas, sartorius, all with two orthogonal views. And that's the major part of the exam. But then you can add different things. Number one, if you have some abnormalities and you want to check it out, don't forget that you have bilateral asides. And so when I work with Dr. Millis, it takes me forever to get through the exam because he always makes me start, do a complete exam on the opposite side, and then come back and do one on the affected side. So it can take some time. Don't forget the dynamic exam. And we'll go through some of those dynamic things that you can actually do. And if I get concerned about there being something more medial, don't forget that you can go on over into a medial exam if you're thinking sports hernia or if there's the lateral hip if you're thinking that that's part of it. And lots of times you have that sort of C-shaped pain. So you're going to probably end up doing that. I probably end up doing a lot of lateral hip exam at the same time. So then the rectus, basically, you know, I started in a pretty sagittal plane and I put my probe right over the AIS. And then to me, what I have to do is kind of take the distal end of my probe and sort of swing it till I get right over a good picture of the rectus tendon insertion there. And then when I want to get to the reflected head, you kind of have to curve it and tuck it down. And many times you're kind of tilting it to get a good view of the reflected head. And so here you go. This is the young man. This was his direct head. And then as I come lateral, you can start to see the reflected head come down a bit. And then bringing my probe way down, you could actually see parts of that coming straight down to the acetabulum. And where that is, is right as it comes under glute men and glute med over that. And then the TFL over the top of that. And don't forget that when the scope goes in, when they do an arthroscope, they're bringing that medial portal right through here. So one of the areas after an arthroscopic surgery where you can have a lot of scar tissue and sometimes adhere it to the capsule is right below the rectus, which can cause pain and stiffness with motion of the joint. This is the short axis view. If I turn 90 degrees and I get to the AIS, and to recognize this, I just come down over the round femoral head. I see the nice round femoral head. I'm in an axial plane. And then just translate more approximately till you get to that bony bump that comes right up. And you know you're right at the rectus and the insertion with the reflected head coming down in this area here. And you can follow it all the way down into the full rectus. Lots of times when I have somebody that's had a lot of postoperative scar tissue and I can't even figure out what the rectus is, or many times a total hip replacement, I go right down to the middle of the rectus, find the central slip, and then just work my way up. And then I can figure out where I need to go from there. So then I turn my probe to a sagittal oblique plane, and I'm looking at the femoral head neck juncture here. And so you'll get a view of this. And you're going to see the femoral head neck juncture. The capsule is really two layers. The capsule starts, of course, at the acetabulum, comes down to the inner trochanteric line, and that's the thickest part of it. And then it comes back along the inner lining of the hip and stops about here. And one thing to know about that is if you stick a needle, if you have to put a needle in the joint for any reason, if you come in here, sometimes you get caught between the two layers. And that's why it's always best to go right about this area here that you're more accurate in getting through and you don't have to worry about pulling the needle back and forth. But you want to look for an effusion. And so an effusion can be up to 7 millimeters, but in most cases, it's about 4 millimeters. Sometimes you can't tell the difference between an effusion and synovitis. And if that's the case, if you compress it, synovium is usually not too compressible, whereas fluid is a good bit more compressible. The synovium, of course, is the inner lining on the capsule there. And if you think that that's what's inflamed, you can always use your Doppler flow as well. And of course, you can look at the labrum here. You have a labral tear. You can look at the capsule all the way up and down. And just as a note about postoperative arthroscopic pain, when you put the scope in, you're coming in under the rectus with that medial portal. And then you're going to cut through the capsule. So when you're cutting through the capsule here, in the old days, like 10 years ago, they didn't even close it. But that was found to be more related to some instability and more postoperative pain. Some people actually went on to PAOs because of it, a periastabular osteotomy. So it's good in that size. You'll be playing from one side to the other and look at that whole capsule, particularly in a postoperative patient. Then you can really get a good view of that. And you can look for loose bodies in here. I had a lady the other day. I should have brought those images. But she had some chondro bodies in the hip that may have been causing some discomfort. And I just brought this up here. I have a very sensitive computer. I just touch it, and it just goes to the next one. This is a kid I saw like two days ago. And I thought it was nice just to show you where you can see the physis right here. So you've got nice, thick cartilage. Because the cartilage you want to sort of assess in particularly older folks, because they're the ones that are getting into trouble. But this is a good view of the cartilage. There's the physis. And I just make a point. One of the reasons why kids that are active and happy may be getting CAMs is because they're constantly banging this physis here against the rim. And that might cause that hypertrophy of the CAM. At least that's one theory. So that's one thing. And so again, post-operative hip pain, you want to look for capsular integrity, both the intra and extra articular scar tissue. And then instability, which I'm going to show you some interesting instability stuff that we're doing. And then look for recurrent labral tear as well as a CAM. So coming out more posterolaterally and tilting your probe, you can sometimes see a recurrent CAM after surgery. And then go to the short axis view. And this is not that patient. I just put this in here because this is another patient of mine that I've been having a hard time with. But she's been getting better. But basically, here's a short axis view where she's got both intraarticular scar tissue and subrectal scar tissue. And after this, we actually hydrodissected right through this area here to try to help her, because she was really stiff and getting any kind of motion there. Then, of course, you want to look at the labrum. And again, here's his labrum, a little suggestion of a tear right there. This was not him. I just put this in here to show a paralabral cyst that can many times be associated with a labral tear. Then you go to the long axis, short axis views of the psoas and sometimes I can get it in one view, but here's with that young man, I started up in the pelvis, I like to get up high and start, look to make sure there's nothing cysts or ganglions or anything up in that area and then work my way down. So here you're up in the pelvis, there's the S-tab in the femoral head. And as I came down, this is over the femoral head and then this is all the way down at the insertion of the lesser trochanter. And it's important to look all the way down there. It doesn't happen a lot, but you can get a tear, tendinopathy, and tendinopathy probably occurs right in this location, far more common than we think. And I've been doing radial and focal shockwave therapy on some of that right there and had some really good success with that as a different orthobiologic intervention. So then I go short axis on the psoas. What you're gonna do is you're gonna find again in an axial plane, just like this probe is right here, you're gonna find the round head and then a femoral head and then translate more approximately to get right in here. And you've got the AIS and there's the tendon there, but then what you've got is the psoas and iliacus. This is the psoas tendon here. And what you have, you have, these are the more menial fibers of the iliacus muscle. And then you have the more lateral fibers of the iliacus muscle, which is out over here, coming up along the inner border of the ilium here. And this is the area they say is much more prone to tearing. And I think, you know, in a couple of cases, I've seen some bad tears of the myotendinous area. It's been in this area right here. So here's an example, this is a different patient, just looking at the, this is actually somebody I just saw about a month ago and she had a tear, but it looked pretty good. But where her tear was right at the distal end of the psoas where it inserts on the lesser trope. And I don't know if you can appreciate it, but there was a little tear right here, which corresponded with an MRI finding that was at another facility. And I ended up just putting a little PRP into that area there and she's doing better. She has some motor dysfunction due to some nerve issues, but doing well from the tendon standpoint. I just pulled this out because I suddenly realized I forgot to put the sartorius in, but the sartorius isn't a common area, in my opinion, of problems. Even with kids, kids have the apophysis there. So they do occasionally get an apophysitis there, but the adults don't see it very often, but you can see it and you'll see some thickening and some hypochloric changes that'll occur right in that area there. So that's an important part of the exam too. Now, snapping. So this is a girl I saw from the Midwest Tuesday and 12 years old, had this really bad pain, it's been going on for a long time. And of course she had a labral tear, but had a lot of snapping. And this is not the greatest snap that you will see, but I could see the snap happen and it was sonopalpably tender and that's right where her pain was. And by the way, I meant to mention that, whenever I examine any of these tendons, I make a note whether it's sonopalpably tender or not, because it makes a big difference because it may just be an incidental finding. So here you go, let me see if I can demonstrate this. So when she flexed up, she just simply flexed it up and drop it down and it would go up and it would pop down right on the iliopectineal line. And do that one more time. So as she flexed up, it goes up into the muscle belly and then it comes down, boom. And that's when she gets her pain. So I was going to inject it, but she was 12 years old, had a lot of anxiety. I believe that yesterday, she had to get something else with IR, so they required sedation. So I think interventional radiology did that yesterday. So then we get to dynamic instability, which is really kind of an interesting topic. And I remember about 10 years ago, working with Mike Millis, we were doing some rounds on some patients and he said to me, he said, what can we do to try to figure out this micro instability thing? And so we're just sitting there and it was a bunch of us around. And so finally I sat down and I said, well, let's just see what happens. And because he kept talking about the apprehension, let me just see what happens when you do that. So we're in the neutral position. This is what you see. So this is the apprehension position, but before you get there, if he's laying down supine, this is actually from the kid that I'm talking about. So this is the actual case. We're in the neutral position. There's the tip of the acetabulum, okay? And so the femoral head just rise a little above it, no big deal, you can have that easily. But then when we put him into extension and external rotation, he popped up about 10 millimeters, which no one knows exactly what the numbers are yet, but that seems more than we typically see. Now I've seen more than that with no symptoms. And I go out and do the physicals at the Walnut Hill Dance School and high school. And then some of those kids move easily one, not a ton of them, but a few of them do. So it's all just another piece of information in your whole thought process. And then recently we started doing the doing this in a standing position. So this is that same girl with the psoas. No, I'm sorry. This is a different, this is a girl with Ehlers-Danlos syndrome, who she's like 21 and she's got this painful hip, but really doesn't want surgery. She got a little label tear, but this is in the standing position. She's got instability popping out. So that's the most supportive that she actually is sublux. She feels it's sublux and you can look and see it's sublux, which I think is interesting. And then this is her in supine position. And I'll see if I can demonstrate that. Just actually this just shows the dynamic of it. So, I'm just going, doing the apprehension position and relaxing it and just doing it again. This was yesterday. So, you know, and most people don't do that. And if you take a look at a lot of people, most people would stay fairly solidly in there, but a lot of these EDS kids have more problem with that. And then the other finding that I found, Marnich told me this a number of years ago was to do the anterior hip impingement where you have your probe basically in an axial position like this, keeping your eye on the femoral head. So this is actually the left hip because there's the acetabulum. And then what you're doing is you're going to internally rotate it. Let me slow that down. And you're gonna look for any kind of soft tissue, i.e. labrum getting pushed up there. But what I find is that I, this, I always get thrown up. Plus, as you can see here, I'm not at 90 degrees. I can get to about 80. Sometimes I can get up to 90. So what I looked at doing was doing it from the anterolateral position. So if you take your probe to the top of the trochanter and put it in the coronal plane and then tilt the top of it about 30 degrees forward, what happens is that you can actually see. So this is the acetabulum right here. This is the soft tissue labrum. This is the trochanter. This is the neck, and this is the head. It takes a little bit to learn this, but when you see it, it's just so much better than the other way of actually looking for any kind of impingement problems. So the ultrasound report, now, it doesn't necessarily have to include all some of those other dynamic maneuvers because some of those are not standard yet, of course. But so you should make a comment on the basic findings that you have. So I put that we did a diagnostic ultrasound of the right hip, and the indications were it was an 18-year-old male with hip pain running and signs of borderline dysplasia, what kind of probe I used, and then my findings, and put in that I correlated it with the x-rays and the MRIs that I had seen before. And then I put down that the femoral head joint looked intact. There was no effusion. There was a labeled tear, and there was some subrectal space. Hold on one second. I gotta move everything around. I can't see. The capsule was normal. On dynamic exam, though, there did appear to be excessive motion, possibly indicating some micro instability. And then I made a comment about the rectus, and even though it wasn't tender sonopalpably, there was a few changes there. And then the psoas looked normal. Long and short axis in the sartorius was normal. In the conclusion, just make the statement about the labeled tear and the instability, and that there was some mild tendinosis. So that's kind of what we do. All right. Thanks, Pierre. That was great. I know for me, I don't see, that's not true. I see a decent amount of postoperative hip patients after PAO and whatnot, and not an infrequent number. At least the ones that I see will have some subjective complaints of instability and for all the world, surgically everything looked fine, and maybe some post-op MR scans look okay. But using ultrasound, I've caught a couple of patients that have maybe some subtle capsular insufficiency, or even some subtle peripheral labral pathology resulting in some complaints and findings of instability. And that's where I think, you mentioned the dynamic nature of ultrasound can be really helpful to identify these patients that are having some of the micro instability. With macro instability, for the most part, your physical exam is gonna be able to capture that. But these cases of subtle micro instability, I think ultrasound can be really helpful. And then the other thing that you mentioned, and I've said this before, and Doug has said this a thousand times, I always comment on spinal palpatory pain. I think it's incredibly helpful because like you mentioned, we see some of these abnormal findings all the time, and it doesn't necessarily mean that they're symptomatic for the patient. So I always comment on a subtle palpation pain provocation. Doug, do you have anything you wanna add? Yeah, Pierre, really nicely done. Just a couple of anatomic points, and then I have a question for you about instability. But for me, there is a fair amount of literature on hip effusions with ultrasound, and there's as much literature refuting numbers as there is supporting numbers. And so probably like you, Pierre, for me, they have a hip effusion if I see fluid. And if I do the same thing, if it's compressible, it's fluid, if it's not, it's probably thickened tissue, i.e. synovitis. And so I don't really use a number of the anterior recess to determine whether there's an effusion or not. If I see fluid, there is, and if I don't, there isn't. You also pointed out correctly that the rectus is a little more complex than it seems. So for those just getting started, the central tendon, which is the most vulnerable tendon for rectus tears, actually becomes the reflected head, and it's the superficial aponeurosis that becomes the direct head. So it's not quite intuitive. And then, again, you nicely point out that the iliopsoas is a complex. And so we should think of it as a complex, and it has a fair amount of heterogeneity. And so if you're someone who's doing a lot of anterior hip exams and looking for a snapping tendon, I mean, sometimes you don't see a predominant psoas major tendon. Sometimes it can be bifed. And there's oftentimes direct attachment of muscle onto the femur. And so it's just important to be aware that there's a fair amount of heterogeneity of the iliopsoas tendon complex, as we say. So Pierre actually showed me his dynamic exam a few years ago, and I've been playing around with it. Pierre, have you done any sort of study or even just informal study looking at normals compared to people that you feel have micro instability? Not yet. What happened just before the pandemic, we got all the reliability done, and then everything shut down. But now, actually, we just had a meeting like two weeks ago. And so we're looking at that in a very short order, within the next few weeks, we're gonna start looking at that. Because, I mean, again, since you showed me that, I do that on some patients and just play around with it a little bit. And I've done it on some people that are asymptomatic. Let's say they come in a younger patient, usually older patients are with lateral hip pain, I see. But occasionally we have a younger patient with lateral hip pain or even a snapping, let's say iliopsoas or IT band. So we're not really worried about the hip joint, but I've played around with it a few times. And I have to say that there are, I think, a number of people who have a fair amount of change, that it's hard for me to know then what is clearly abnormal or not. And so I think that that approach would be really useful. I think it's another, so this young guy that we presented, so he's got borderline dysplasia, he's got a labral tear and he moved a fair amount. So if you're gonna do an arthroscope on him versus a PAO, because that'll accomplish a discussion, would you just reef the capsule real well or use cadaver graft to reef it? And so the meaning of it is sort of like, I think maybe more like you just said about exactly what's normal and not normal, but as just a piece of information to go with all the other radiographic findings, I think it either right now would have some meaning for the intervention if he has intervention. Right, right. You know, the one patient that absolutely is maddening for me is that one that has this sort of deep anterior click and you sit there with the probe and you try to find it, you can try to find it, you move the probe different ways and you just can't see it and they can demonstrate it. I don't know if you have any insights to that, but I find those maddening sometimes. And everyone thinks it's the labrum. Occasionally it is, but it's not very common, I don't think. Yeah, yeah. But anyway, it's certainly, you've created a niche. You see a lot of patients with this. You're very good at it. And we look forward to learning more information on micro instability. I'll make sure we get that study going. Thank you. Hey, Pierre, can I just ask one quick question before we end this? So when I'm doing dynamic scans for anterior hip instability, I'm almost always doing them supine and trying to provoke symptoms with that hip extended abducted, actually rotated position. And you had shown on your case, trying to provoke instability symptoms, both, I'm sorry, supine, but supine, as well as standing. What have you seen comparing the two approaches in terms of sensitivity to capture micro instability or provoke symptoms? Is one better than the other that you've seen or are they comparable? Well, in my mind, the standing one makes more sense because then you're actually replicating what they're going through on a daily basis. So it's one of the, that exam we just started recently. So we haven't got a ton of data yet on that. So we'll get back to you as we get more and more information. We're also looking at posterior instability too. If you, I didn't want to go there because it's not, this talks about, but if you put them in the lateral decubitus position, flex adduct and internally rotate, and before that you get them sort of in a neutral position and watch it pop out back. I think some of these EDS kids will come back out. And so of course, if you've got, you know, retroversion with poor coverage posteriorly of the acetabulum bony wise, and then you're popping out because of some ligamentous laxity, that wasn't part of your question. I would say intuitively, I think the standing one is better, but, you know, we have the most data on the apprehension test at this point in time. Great, thank you, I appreciate that. All right, well, thanks again, Pierre. That was fantastic, incredibly informative and educational. So thanks so much for hopping on and doing that with us today. Oh, thank you, thanks for inviting me, I appreciate it. All right, so that is it, we're off next week. Back on the 15th of October, Dr. Adam Smarsky is going to be giving a talk on ulnar nerve instability at the elbow. Otherwise, everybody have a great Friday, great weekend. We'll see you in a couple of weeks.

3rd Edition, CASE 25

3rd Edition

Hip

hip labrum tears

borderline hip dysplasia

sports ultrasound

dynamic exams

anterior hip pain

micro-instability

ultrasound imaging