The Bone Whisperers

Operation of the Century: Hip Replacements

Episode Summary

It's called the Operation of the Century for a reason - hear the latest advances in hip replacement surgery.

Episode Notes

Dr. Laith Jazrawi and Dr. Vinay Aggarwal of NYU Langone Orthopedics explore the latest advances in hip replacement surgery advances, from robotic surgery to rehabilitation & recovery. 

Episode Transcription

Narrator: SiriusXM presents an NYU Langone Orthopedics podcast. Orthopedics is just very important to the population in this country. Its ability to restore patient function. Problems related to cartilage, to someone who has more advanced forms of arthritis.  Getting people back to their activities and the things that they like to do. Featuring NYU's experts in the field of orthopedics trying to figure out that problem before it even is a problem. Problems with solutions. Well beyond physical therapy, to conservative pain management, to surgery. The best medical minds now come together. Applying all of our minds to solve these problems. We're here to get people feeling better so they can get back to their lives. And that's really what we try and accomplish. These are the Bone Whisperers.

Dr. Laith Jazrawi: This is Laith Jazrawi, Chief of Sports Medicine here at NYU Langone, and today we're continuing our Bone Whisperers podcast series, and today we're going to talk about surgical approaches to hip replacement. Front, back, and everywhere - which way are you most comfortable with, or which way is your surgeon most comfortable with and what leads to better outcomes? And today we have, as our guest speaker, Doctor Vinay Aggarwal. He's assistant professor here at NYU Langone Medical Center. He's Chief of the adult reconstructive service at Bellevue Hospital, and he's also the associate fellowship director for the joint replacement fellowship here at NYU.

Dr. Vinay Aggarwal: Thanks for having me here, Laith, uh, this is a privilege to speak to you about this topic, something that I am very passionate about and something that I think a lot of our listeners would benefit from understanding. Uh, what's out there on the Internet, what's out there when they visit their doctor's office when it comes to getting a hip replacement.

Dr. Laith Jazrawi: You know, I think the one thing that's very interesting, you see these patients who've had hip replacement, and I'm a sports surgeon - I don't necessarily take care of these patients - but it's incredible. Some of them, on day one, are walking with only a slight limp and look great. When I trained, Vinay, we used to do this posterior hip replacement, and I, you know, and cutting through the muscle in the buttock area from a posterior approach, and you'll get into that - but I never saw them walking that easily right away. So can you tell me a little about, is that true, that one approach is that much better than another approach in terms of getting these patients walking right away?

Dr. Vinay Aggarwal: Yeah. I'm glad you bring in the historical perspective on this, because yes, you're absolutely right. We've come such a long way from even the last 20 years of hip replacement. But you have to understand, hip replacement actually goes back 50, 60, almost 70 years at this point. Hard to believe, but in the 1960s, uh, Sir John Charnley, who's credited with today's modern day hip replacement, did a lot of work in England, and all that work came over to the United States. And back then, people were on bed rest after hip replacement. So people were in the hospital for extended periods of time, not allowed to walk, etcetera. And a lot of that had to do with how the soft tissue was handled, how they got into the hip joint. So, giving you a little bit of background on what happened, it was a very, very successful hip replacement, don't get me wrong, but they would cut through a lot of muscle, something called the direct lateral approach. And then if you feel on the side of your hip where your pant pocket is, that's the hip bone that people most feel comfortable speaking about. That's actually called the trochanter in orthopedics. And that hip bone was actually dissected and what we call cut off or osteotomized. And that's how they got into the hip joint. They cut the bone, they cut the muscle, and they got into the hip joint, and they did the hip replacement, which was extremely successful. But as you can understand and as you can hear, somewhat violating.  And so that's a lot of the reason why patients had a limp afterwards. It's called a Trendelenburg gait. That's what we talk about in orthopedics, when a patient is wobbling when they walk after any kind of surgery, when that muscle and that trochanter bone is violated, they got that big lurch. And so, since then, the sixties evolved, the seventies evolved - people have gotten more and more what we love to use in surgery as the term minimally invasive with their approaches. And we'll get into a little bit about what the different approaches that are used today are. I'm not going to kind of go and spill the beans right away. We'll talk about that today. But suffice it to say that we have come a long way. People are absolutely walking better, and surgical approach and soft tissue is absolutely a piece of the puzzle. But as we'll talk about, it's one piece.

Dr. Laith Jazrawi: So, Vinay, you were getting into it, but do some people still do the posterior approach today in terms of approach and hip replacement? And is that wrong? Because I've heard a couple of patients go, no, no, no, he doesn't do the anterior approach, I want that, and my answer to them is always, you should go to your surgeon with the approach he's most comfortable with. Can you highlight on that and expand on that?

Dr. Vinay Aggarwal: Yeah. So, just to give, you know, a little bit of background for listeners on the different types of approaches. Yes. There are three main approaches still in use today, and that's the direct anterior laterally-based approaches, which includes kind of the direct lateral from the sixties and seventies in Europe. It's still very popular in Canada, or anterolaterally based, which is a little variation of that lateral approach, and then the posterior approach, which is a traditional approach - very, very popular in America. To give you a sense of the breakdown of who's using what. In about 2017, a survey of the United States surgeons - about 75% were using a posterior approach. And only about 20% or less were using a direct anterior, but it was rapidly on the rise. So since 2010, the direct anterior has just been skyrocketing. And really, in the last five years, it skyrocketed significantly to the last survey, I believe the numbers at the American Association of Hip and Knee Surgeons was something around a 50 50 split. So that's a massive change, a massive change in what people are doing, what people are being trained on in hip replacement. And so what I mean by 50 50 is 50% posterior, 50% anterior. There's a sliver of surgeons, probably less than, you know, 1 to 2% in the United States at least, that are still doing laterally based approaches. It's a very successful approach still. It's tried and true, time tested, but there are some advantages and some disadvantages which we can get into of each approach.

Dr. Laith Jazrawi: So it's interesting just to parallel it in sports. Initially, when ACL reconstructions were developed, we had these big incisions, and they went down, as the arthroscope was developed to smaller incisions. But we use these, what we call outside-in drilling techniques to drill the reconstruction in a more anatomic position. We went away from that and started doing even more minimally invasive, but we did a different approach. So the initial approach was outside-in when it first started ACL, when we first started ACL reconstructions. And you know what? We're back to that now, you know, so it's almost a back to the future type thing. It's not exactly like this, because it sounds like the first hip replacement sort of done through a direct lateral approach, but it is interesting. And just getting back to the point you made up this trend towards surgeons shifting to the anterior approach - why is that? What is it based on, other than you talking about going through all this muscle in the back? Tell me a little bit about the issues, why one approach may be preferred over the other, and what's the pros and cons of each of those approaches?

Dr. Vinay Aggarwal: The direct anterior approach has actually, believe it or not, been around for about 30 to 40 years - it's actually been around for hundreds of years when we're talking about trauma surgery and wartime orthopedics. Getting to the hip joint from somebody's anterior side or the front while they're laying down on their back, and the surgeon goes in directly from the front - that's been around for hundreds of years at this point. It's called the Smith Peterson. And one of the advantages that it's been developed for hip replacement is you can really go between muscle intervals without really having to do a lot of dissection, of peeling muscles and cutting muscles. So you really just spread muscles, go in between them, and it takes advantage of that interval between the superficial muscles and the deep muscles to get down to the hip joint pretty quickly. Now, the disadvantage of this approach, there's two:  One is that there's no question people will say that getting the femur or the thigh bone exposed to put the implant into the thigh bone is a little bit more challenging than with a direct lateral or a posterior approach. And so early on, once this approach was getting popularized, there was a lot of complications people had related to the femoral side, in other words, putting in that implant into the femur. A lot of people got broken bones, fractures in the surgery, fractures after the surgery because the implant wasn't put in correctly on the femoral side. Sometimes the implant would sink down because it was too small, the surgeon couldn't get appropriate access. But the other thing I want to mention is, as people have become trained more on anterior approaches, some of these early learning curve complications have certainly gone away. And it's interesting, when you look at our graduating fellow classes, we've had four years in a row where 100% of the fellows raised their hand when I asked the question, what approach are you going to use for hip replacement - 100% have said direct anterior. And it's actually become interesting that some of the fellows, the trainees that come into our institution now, have never even seen a posterior approach in residency. It's becoming rampant. And we can talk about whether that's good or bad, but there are certain, absolute, certain advantages with the muscle sparingness the early recovery. But there's still some disadvantages out there, and we'll get into a little bit about why you may have a surgeon pick one over the other.

Dr. Laith Jazrawi: So what is the problem? We've been hinting at it with this posterior approach, and you're going to elaborate on it, but there's two bad things that I think can happen after a hip replacement. It's an infection - a deep infection, which is a pain in the neck, sometimes requires the implant to be removed, long term antibiotics, really a mess. And then the other one, which I remember as a resident having to put these back in, was a hip dislocation. And I remember when you did a posterior approach, that that was one of the problems. You can dislocate your hip, and they did all these things to try to prevent that, but it still happened. So you can highlight on that.

Dr. Vinay Aggarwal: So infection goes without saying across the board, no matter which approach you have, infections are risk. And we actually looked at this, and early on, actually, it was interesting. The anterior approaches actually got infected more often, and I think that the reason it, uh, was probably a longer operating time, people weren't used to how to do the surgery properly from the front, that's kind of gone down over the years. The skin in the front is a little bit more fragile, and so it doesn't heal as well. So you may get some superficial infections. But from the back, you're right, dislocation is certainly a huge risk. There's been a lot of research about dislocation after hip replacement, and thankfully, with today's modern day implants, we've gotten this down to a less than 1% risk, regardless of what kind of approach you go. So the problem is, people do state that the anterior approach has lower dislocation rates. The good news for the patients out there is that we're talking across the board, it's less than 1% regardless of the approach. And so when you're comparing two times higher rates of dislocation with posterior versus anterior, we're talking about a 0.9% versus a 0.4%, which is actually significant when you think about thousands of patients. But at the individual patient level, it's not such a big deal. And that's a lot of it, thanks to our implant design. And a lot of it is technology: Navigation technology, computer technology, robotic technology. It's really made our lives easier as surgeons, putting these implants in the right spot so those complications don't happen.

Dr. Laith Jazrawi: So it sounds like if you, and I'm sure a lot of the listeners to this podcast really want to get down to it, if your surgeon in your area where you live does the posterior approach, does a good job, he's got - there are patients out there, friends of yours, that have seen those patients and are happy, and you're reading all about this anterior and posterior approach, what's your sort of advice to that patient? How would you counsel them if they were a friend and called you up and said, hey, I got this guy. He's a really good surgeon, but he does the posterior approach?

Dr. Vinay Aggarwal: I think that it's very interesting how there's been a lot of direct to consumer advertising on the approach. Right. It's not that often, like, I don't know, in sports surgery, for example, if you guys have direct to consumer advertising on certain technical aspects of a sports surgery. It probably is out there. You know, there are probably patients that get sold on implants, et cetera. But this is one where the direct to consumer marketing on a certain approach to hip replacement - I can't remember anything so vastly available, whether it's the New York Times articles or Internet marketing. So this is definitely something that I see in my office, as you mentioned, all the time. It's actually gotten a little bit better over the years in terms of patients not asking for so much. My advice is exactly what you said. This is wise words from one of a couple of my mentors, Kevin Bozik and Stuart Goodman, out in the east coast and down in Texas: Patients should go first and foremost to a surgeon with a good track record and a good rapport with you. If you don't trust the hospital system you're entering into or you don't trust the surgeon and their team, it doesn't matter what approach they use, it doesn't matter which implant they use. You have to trust that they're going to do a good job and they're going to be there for you personally. And the bottom line is, because we've done a lot of research on the outcomes after each of these approaches, I can give you the good news that at six weeks, I don't really care how you get into the hip joint, anterior, posterior, lateral, whatever - if you put the implants in the right spot, patients do phenomenally. It's called the operation of the century for a reason. Hip replacement is just so successful. And like you said, people are really getting up and at it right away, no matter the approach, they're getting right out of bed, we're getting them out of the hospital the same day. You know, I did five hip replacements last week. Four of them went home the same day. It's just a testament to not, um, just the approach, but the whole process of surgery. And if you trust the hospital system does a good job of doing these surgeries, then, uh, really, the other stuff becomes moot.

Dr. Laith Jazrawi: I'm sure the listeners, they want to know - you talked about these five hip replacements. What is your preferred choice or approach? And then also tell me, why would you select, are there specific patients? Depending on what your answer is, either the anterior or posterior approach - is there specific patients that you would choose one approach over the other?

Dr. Vinay Aggarwal: Yeah, great question. So I personally started my practice doing extremely complex hip replacements, and that means people who have a lot of deformities, they've had their arthritis for a long time, they have congenital issues. Those are very challenging cases to do through minimally invasive exposures. And so I got very good at doing the posterior approach, and I got better at it with time, making it smaller and more and more minimally invasive, as a lot of people have over the years. So now we do a mini posterior approach, and I did all four of those patients through the back, and I think that a lot of my posterior approach colleagues would agree - if you do a good job and you really don't violate a lot of the muscles, you still get these patients out the door very quickly. Their recovery may be a little bit less robust in the first two weeks we're talking. But what I tell patients is, look, this is an operation that I'm doing to make it last for the rest of your life, 20, 30, 40 years. Understanding that the first two weeks may be just m a smidgen more painful or a little bit slower, they get that trust in me that I'm going to do a good job. And when they hear that, yeah, they're like, yeah, doc, I get it. You want to do a good job. And I've had no issues looking back on that. I did early on, want to do direct anteriors for the very straightforward, good bone quality patients, and I think those are the best patients to do it on. Not a lot of deformity, active patients, good bone quality. You get into trouble a little bit when they have osteoporosis that's severe. Those bones can fracture a little bit more easily when you're trying to expose and get the femur exposed, for example. But, you know, there are certain patient population, morbidly obese patients, not, um, the best to do direct anterior, very difficult to get into the femur. Very, very muscular males, very challenging to get through the muscle tissue and get that femur. So if you're a very, very muscular male with a lot of leg muscle, butt muscle, it can be challenging to get into those patients. Patients with what we call kind of the Mickey Mouse pelvis. So, on an x ray, big pelvic wings called the iliac wings, if you have really big, wide pelvic brims, can be also very challenging to do direct interiors. And then posterior approach - obviously, the risks are, if you have somebody who's really demented, very high risk of dislocating, somebody who's got neurologic issues, Parkinson's, et cetera, falls a lot - those may not be the patients you want to do through the back. Direct lateral, certainly, in addition, has really helped mitigate dislocation risk factors. But again, I'm going to go back to what I said originally. If you're a patient looking for a hip replacement surgeon, and you're looking to see what approach you need to feel comfortable with the doctor. Certainly do your research and find out from your friends, your loved ones, what they've had, what's been successful for them. But I can guarantee you'll find patients out there that have had a very successful hip replacements through the front, through the back, through the side. And they all just probably love their doctors, love the hospital systems that they work with. That's the key.

Dr. Laith Jazrawi: That's great. What about, I guess, the next question. If a patient comes in with a failed hip replacement? I know they're rare here, but is it common to just go through the prior approach that they had, or would there be a reason to change the approach? And is it easier to go through an approach which hasn't been sort of tampered, or is what we call a virgin approach? What's the thought behind that?

Dr. Vinay Aggarwal: Yeah, I mean, look, we are lucky that we have a very low revision rate at NYU, but that does not mean we don't take care of revisions from outside. We get tons of referrals, a lot of places around the New York City area, myself, my colleagues, we do a lot of complex surgery. And, um, yeah, a lot of the patients are getting approaches all over the place. Direct lateral. Direct anterior. Posterior. For the most part, I can tell you that if it's anything other than a very simple revision, a very simple revision being, you know, doc told me I just have to get the ball and the liner changed out kind, um, of like a tire change, if you will. Those, uh, are the simple ones that people can do from the front. But when we're talking about, oh, you know, I broke my femur, fractured by my hip replacement, or, you know, my socket is completely loose, or my stem is completely loose, uh, in the wrong position, or I got an infection. Those are the ones that a lot of us revision, high volume revision surgeons do from the back. Because of the exposure issues that I mentioned earlier, it's very easy to see everything you're doing when you go through the back. And not only that, but you can extend your incisions in either direction, meaning you can make the incision bigger, both at the bottom of the thigh and then up at the top of the butt, if you need to, to get more visual access to the hip to do the complex work that may be required. Now, that being said, just as direct anterior hip replacement for primary hip replacements or first time hip replacements got popular 10-15 years ago, I can tell you what - direct anterior revision hip replacements is the hottest thing in the joint replacement world right now. It is the hottest thing. A lot of people are learning about it. A lot of people are trying it out. Uh, and time will tell. I, um, think it's going to be interesting to see the next five years of that.

Dr. Laith Jazrawi: Is it one of these things where it's just a technically more challenging thing, and once you learn sort of the basics, you then push yourself in the O.R. and take those techniques you learn with a primary and try to apply it to the revision case?

Dr. Vinay Aggarwal: Absolutely. I think it's a pushing yourself to the limit. Patients probably will do overall just as well when we get this thing solidified in terms of the learning curve, as we talked about earlier. But, yeah, it's something that you have to get more and more comfortable with. You have to get more teachers out there. But for the patients, again, you want to go to someone, like we talked about, you got to go to someone you're comfortable with and someone that knows what they're doing and does a lot of these. That's the bottom line. So we do a lot of them here at NYU. I think if you're going to have a revision hip replacement, you should really go to someone, again, not for their approach, but for their expertise in knowledge in the subject matter.

Dr. Laith Jazrawi: If you're just tuning in deep into this podcast, you're listening to the Bone Whisperers podcast here at NYU Langone Hospital. And we're talking today to doctor Vinay Aggarwal, assistant professor here at NYU Langone Health center. He's chief of the adult recon service at Bellevue Hospital, which is one of our affiliates here at NYU Langone. And he's also associate fellowship director of the adult Joint Replacement center here at NYU. And I'm Laith Jazrawi, chief of sports medicine here and professor of orthopedics, asking him questions and really probing, you know, the approaches to hip replacement. And what we've come up with so far, it seems like there's a 50 50 split with anterior hip replacements and posterior hip replacements, and it's not so easy that one is certainly better than the other. I guess my next question and what we're going to lead into is what you had spoken about and alluded to was about the use of robotics, navigated surgery. This is a hot topic, too. Patients are, I'm certain, are asking about this when they come into the office. And tell me a little about that in orthopedics and particularly hip replacement.

Dr. Vinay Aggarwal: Yeah, I think this is just as hot. If you said approaches about five years ago, robotics and technology is today. So that's where it comes in - it's absolutely everywhere, whether it's the implant companies, whether it's the hospital systems, whether it's the surgeons, whether it's the patients. Everyone is talking about robotic hip replacement, robotic knee replacement, and computer assisted surgery. So there's all kinds of technologies out there, I can boil it down to this: They have made them approach specific. So whether you're an anterior surgeon, a direct lateral surgeon, or a posterior surgeon, there is robotic technology out there for you. It's mostly based on putting the implants in the right position. That's why they're out there, this technology. It's not necessarily to take over the labor or the job of the surgery. That's probably what patients think first and foremost, when they think of a robot doing the surgery. Oh, you know, the surgeon's standing there and the robot's doing the surgery. Well, that's not necessarily what it is. In hip replacement, what it is is getting landmarks, exact measurements of your bone, rather than kind of, you know, just the old eyeball method. But getting exact landmarks of the bone so that to your personalized anatomy, we can put your hip replacement implants, your socket and your stem, and we're talking to degrees and millimeters, stuff that we've never, ever thought about before, stuff that was never available in the sixties, seventies, eighties, nineties, and the early two thousands, and really get those implants to be long lasting, last 30, 40 50 years for the rest of your life, and not have to worry about it with dislocations. Not have to worry about it with limb length discrepancies. So these are available whether you're an anterior approach surgeon, whether you're a posterior approach surgeon. Now, the key is that technology, when we talk about research, it has shown that it's definitely helpful. Okay, so our outliers, in other words, the implants that are put in, are less and less put in the wrong spot compared to nowadays. They're all tightly bundled in a much more appropriate position than they were 15-20 years ago without the technology. So I think most approach surgeons are using some form of technology, whether it's navigation, computer assistance, robotics, some form of technology is the way to go.

Dr. Laith Jazrawi: So just to explain further to the audience, when you talk about the use of a robot, is it really that the robots sort of a navigation system to help you make the cuts or guide you where the cuts should be made?

Dr. Vinay Aggarwal: Yeah, there's several types out there. I'm not going to speak for every single company because there are different types and different nuances we won't get into. But suffice it to say that the robot itself is coming in to help guide the implant positioning and help to prepare the bone. Like you said, cutting, reaming, milling, whatever you want to call it, prepare the bone in a very, very specific fashion. So the implant goes into that prepared bone very precisely and therefore very accurately.

Dr. Laith Jazrawi: So, similarly with in my field, in sports medicine, we do a lot of cutting of the bones to realign them and put them in at different angles. And what's popular now for us is the use of this technology for navigation and navigating our cuts and telling us with these 3d printed cutting guides, and you're absolutely right, it makes the surgery more accurate. I think the outcomes are better. It is the way of the future.

Dr. Vinay Aggarwal: It's nice for patients because obviously, when you're a patient and your doctor says, like, we're going to be more precise with this, that's something good, right? That's something where I'm going to leave the doctor's office feeling more comfortable. But I can tell you, for the patients out there, as a surgeon, it makes me sleep so much better. Also, I go home with the confidence. I leave the OR knowing, look, I put that thing in the right spot, I know it's going to be successful. Obviously, complications happen, but this is something that has lowered my personal stress about surgery in general to a tremendous degree, whether it's a primary hip replacement or revision.

Dr. Laith Jazrawi: Absolutely. So as we wrap up, hip replacement, and I agree, coming from the sports perspective, hip replacements, they're the happiest patients that walk into the office. They love their doctors 100%. They love that procedure. So what's the future hold? It seems like, at least in your world, you've gotten this down pretty well. You've got the robotic thing, navigation thing. You've got the approaches down. You've got the implant designs where they're not dislocated anymore. What's the future? Is there an implant that will last forever type of thing? And I guess from my standpoint, that's the only thing I can think of. Am I right on that? Is there anything else that you can improve?

Dr. Vinay Aggarwal: Look, there's always room for improvement. This is extremely challenging when we're talking about hip replacement, because you're right, it is the happiest patient population. It's a reason why I went into the field. It's a reason why a lot of our medical students see our patients afterwards, so thrilled, getting back on their feet. But you're right, you know, we've made a lot of advancements, approaches, implant technology, implants themselves. I think, you know, there's two things. One is surgical approach is one piece of the puzzle. We didn't talk a lot about it, but I'm just briefly touch on all the other aspects of surgery that you don't think about as a patient. The preoperative education from nursing, the anesthesia, the pain management afterwards, the physical therapy and rehab. All of this has been exponential in terms of why we at NYU and why as a field, we've been able to get patients out the door day one. A little bit is approaches, a little bit is implant, but all of that stuff can't be understated that I just mentioned. It's a team, right? We have a great team. It starts from preoperative nursing, phone calls. It starts with doctor's visit. It ends with physical therapists on the back end. All that has advanced tremendously, and I think we're going to continue to do that. But then when you think about really how to make this surgery foolproof, we're still figuring out as our population ages, as our population may become more obese, how do we get these things to not become infected, and how do we get these things to not loosen or dislocate? Those have been getting lower and lower numbers, but if you look at them, there's been a little bit of a plateau in our ability to fight infections. And I think that maybe antibiotic-coated implants are the way of the future - those that are going to last forever without getting infected no matter what. It's a lot to ask for, but it is something on the horizon. And then secondarily, we're thinking about implants that may be extremely personalized to the point where really minimally removing bone so very, very small implants that don't remove much bone so that patients can retain part of them as much as possible while still being extremely happy and functional.

Dr. Laith Jazrawi: Well, that's just wonderful. Again, thank you for listening to the Bone Whisperers podcast here at NYU Langone Health. We had Doctor Vinay Aggarwal, today chief of the adult reconstruction service at Bellevue Hospital, also the associate fellowship director for training our residents, or in this case, training our fellows who come from outside institutions to train with us to learn advanced techniques in joint replacement. Thank you again, and thank you for listening to this series.

Dr. Vinay Aggarwal: Thank you for having me, Laith.

Narrator: The Bone Whisperers is a co production of NYU Langone Health and SiriusXM. The podcast is produced by Scott Uhing. Sound design by Sam Doyle. SiriusXM's executive producer is Beth Ameen, and senior operations manager is Emily Anton. Narration and additional sound design by Michael Luce. Don't miss a single episode of the Bone Whisperers and subscribe for free wherever you listen to podcasts. To hear more from the world-renowned doctors at NYU Langone Health, tune in to Doctor Radio on SiriusXM on channel 110 or listen anytime on the SiriusXM app. For the Bone Whisperers podcast, I'm Michael Luce. Join us next time for the latest advances in orthopedics on the Bone Whisperers.