kayalortho Podcast
I would like to take this opportunity to welcome you to another episode of the kayalortho Podcast. My name is Dr. Robert A. Kayal, and I am a board-certified Orthopaedic Surgeon and Founder, President & CEO of the Kayal Orthopaedic Center. We are a large multi-specialty and multi-disciplinary musculoskeletal medical center in Northern NJ and NY, specializing in orthopaedic surgery, interventional pain management, rheumatology, podiatry, chiropractics, physical therapy, massage therapy, acupuncture and high-resolution, cross-sectional medical imaging. For additional information or to schedule an appointment with one of our health care providers, you can contact us at 844-777-0910 or at kayalortho.com.
kayalortho Podcast
Unveiling the Intricacies of Revision Hip Replacement Surgery with Dr. Gerald Andah
Ever wondered how advances in orthopaedic surgery, particularly hip replacement, have revolutionized patient care in the last few decades? Join us for an enlightening conversation with Dr. Gerald Andah, a fellowship-trained orthopaedic joint replacement surgeon at the Kayal Orthopaedic Center, as we dissect the intricacies of revision hip replacement surgery. Immerse yourself in the realities of the surgical world as we talk about the durability of hip replacement implants and the remarkable strides made in this field.
Warning signs post-surgery are not to be taken lightly. A major aspect of our discussion involves the significance of post-operative follow-up care, and how to interpret symptoms that might indicate complications such as implant failure or infection. Take note as we discuss practical ways to reduce pre-surgical bacterial levels and the importance of maintaining optimal health and nutritional status. We'll also delve into the potential consequences of ignoring persistent pain after a total hip replacement – a situation that demands immediate medical intervention.
We round off our conversation by discussing possible complications that could arise from hip replacement surgery, such as implant failure due to wear and tear, osteolysis, instability, and leg length inequality. Hear Dr. Andah explain the techniques adopted in revision hip replacement surgeries, including the use of modular implants that provide a customized approach for each patient. Don't miss out on the valuable advice on maintaining open and regular communication with your orthopaedic surgeon and why follow-up visits are crucial in ensuring the success of the surgery.
Hello and welcome to another edition of the K Lortho podcast. Today is August 23, 2023, and today's special guest is our very own Dr Gerald Anda. Dr Anda is a fellowship trained orthopedic surgeon with an expertise in hip and knee primary and revision joint replacement surgery. Welcome to the podcast, dr Anda. Thank you so happy to have you with us today. Thank you for having me here. So today's topic is revision total hip arthroplasty. Why don't we take this opportunity, dr Anda, to introduce yourself to our listening and viewing audience before we start this podcast?
Gerald Andah, MD:Yeah, absolutely so. My name is Dr Anda. I'm from Ghana originally. I went to school at Penn in Philly for about 13 years, did the first half of my training there and finished up with a fellowship in adult reconstruction, which is basically hip and knee replacements, at Montefiore in New York City.
Robert A. Kayal, MD, FAAOS:Okay. So it's so good to have you with us, dr Anda. Why don't we just take this opportunity first of all to just inform our viewing and listening audience about hip replacement surgery and revision hip replacement surgery in particular?
Gerald Andah, MD:Right, absolutely so. Most people know about primary hip replacements, which is having your hip done the first time around, but sometimes there are situations in which you're going to need to have it redone, which is what we call revision total hip arthroplasty.
Robert A. Kayal, MD, FAAOS:Okay, great. So what are some of the reasons that people would sometimes have to encounter the need for revision? Hip replacement.
Gerald Andah, MD:Right. So actually, if you could believe it, the most common reason for needing to have a revision total hip arthroplasty is not having it done by myself or any of the other surgeons that care orthopedics.
Gerald Andah, MD:Okay, no, but on a more serious note, the most common reason is loosening, and that can be for two different reasons. It could either be aseptic or septic. All that means is that one could be without an infection and one could be with an infection. Some of the other reasons for needing a revision hip replacement are instability, and so, as you know you know, hip replacement has a ball in the socket, and so sometimes that ball can pop out of the socket, and so that's another reason, and that can happen for multiple reasons, but that's another reason why you might need a revision hip replacement.
Robert A. Kayal, MD, FAAOS:Yeah, so how long are these primary hip replacements supposed to last in?
Gerald Andah, MD:general. So, while the longevity of these implants the literature tells us is about 80 to 90%, of them are still good at about 20 to 30 years.
Robert A. Kayal, MD, FAAOS:It's incredible. They've made some significant strides over the years, absolutely, and in hip replacement and knee replacement surgery in particular. And what are some of those things that affect the longevity of implants?
Gerald Andah, MD:So some of the things that affect the longevity of the implants is the durability of the materials that are used for the total hip replacements. There have been so many advancements in the last you know, 10, 20 years that make these implants so much more durable that you know the literature itself hasn't even caught up to how long they last. To be honest, the liners that we use, which is the sort of cushion in between the two parts of the implant, is so durable now that we're not seeing the same problems that we were seeing, you know, 10, 20 years ago as frequently. And then the materials that the actual hip implants are made of are titanium, and so they're very durable and they you know they last a very long time.
Robert A. Kayal, MD, FAAOS:Yeah, and I don't think we want to talk about today the basic fundamentals of hip replacement surgery because, as you know, we already discussed primary hip replacement surgery with Dr Victor Ortiz when we focused on the direct anterior hip replacement. But I think it's important for our listening audience and our viewing audience to at least get a nice visual of some of the implants that we're talking about when we're talking about hip replacement surgery. So can we first demonstrate to our patients the components involved in hip replacement surgery, so that they can get a better understanding when we talk about why and when some of these implants fail, what needs to be done to fix it Absolutely.
Gerald Andah, MD:So we're going to start out with the acetabulum, which you can think of as the socket component for your hip replacement. So, as you can see here, it's a hemispherical shape, okay, and it has these holes in case you need to put screws in it to increase the stability or fixation. The other part of this component is this liner in the center of it, and this is what I was talking about as the cushion that you know. It provides a buffer between this and the other aspects of the total hip replacement. So this liner is what has had, you know, so many changes happen over the last few years to make it so durable that these are lasting even longer than the 20, 30 years that we're accustomed to having it last.
Robert A. Kayal, MD, FAAOS:Right. So, just so the patients are clear, the first thing we do when we do a hip replacement is we dislocate the hip right. The hip replacements are traditionally done for hip arthritis, when there's a bone on bone, arthritic, painful condition, right. So we have to provide the patients with a new what we call a bearing surface right and in the hip it's a ball and socket joint, just like in the shoulder it's a ball and socket joint. So what you're holding up in your hand is the socket of the ball and socket joint, right.
Robert A. Kayal, MD, FAAOS:So the first thing we do, as Dr Ortiz and I have discussed in the past, is we first prepare the acetabulum. So we ream the acetabulum with instruments to prepare a hemispherical socket to allow us to install that shell right, what we call the shell. Once that shell is seated into the bone, it's a nice press fit fixation. Typically, sometimes we'll have to augment that with screws to supplement that fixation. But then the new ball you put in has to articulate with something, and that's something is that plastic liner that you described. So so far we've talked about the shell and we've talked about the polyethylene liner or the plastic liner. Now that liner could be made up of different materials, but most commonly we're using, in 2023, a plastic or polyethylene liner, right. So let's talk about the stem now.
Gerald Andah, MD:So for the stem, this is an example of a primary hip replacement stem where you can see that it has the bulk of its shape in the in the proximal or top part of the implant. This fits in the proximal part of your bone, that's called the metaphysis and this fits in the actual canal of your femur. So this is the stem portion of your hip replacement. You can see that it has some quoting around the implant here and that helps bone to grow and attach to the implant to increase the stability.
Robert A. Kayal, MD, FAAOS:Right, and some of the innovations in orthopedics, especially joint replacement surgery, have largely been made in the implants themselves. It's not just the way that surgeons are performing the hip replacement, but the vendors have contributed significantly in the technological advancements of total hip replacement surgery too, by providing us with better products, better implants, absolutely, and we'll talk about that more in detail in the future.
Gerald Andah, MD:Yeah absolutely so. One of the things that has changed over the years is the shapes of these implants. Right, they have all sorts of tapers and they have different shapes and sizes that allow it to fit into the bone more specifically, yeah, and the materials as well.
Robert A. Kayal, MD, FAAOS:Some of them used to be very stiff and rigid, and now the stiffness associated with these implants, especially these titanium implants, is much more bone-friendly, where these implants will now become more load sharing devices as opposed to load bearing devices, which has significant impact on the longevity of the total hip construct correct, yeah, and so the materials that they're using for these implants now match a lot more closely the stiffness of our bone, and that allows it to distribute force more evenly throughout the bone.
Robert A. Kayal, MD, FAAOS:Right. So, dr Andow, why don't you describe what I'm holding in my hand right now and you can show our viewing audience how a total hip replacement construct is put back together during?
Gerald Andah, MD:surgery, absolutely.
Gerald Andah, MD:So what we're looking at here is half of your pelvis right here, and then this is the top part of your femur right, and so when we're doing a hip replacement, you can see that this socket is prepared for this implant to fit in in a press fit way, which sort of means that we're using the friction of the implant to hold it in place and the bone grows into it over time.
Gerald Andah, MD:This is that liner that we've spoken about that provides a cushion between the other part of the implant that I'm about to show you and this socket implant. So this is the proximal or top part of your femur right, your thigh bone, your thigh bone, where the stem of the implant is going to sit, and it literally fits in there like that. It's just like that, especially when we're in surgery too, and then we relocate the hip, so you have the ball fit into the socket, just like that, okay, and then eventually, I'm just gonna take this apart, actually, and show you guys, this is how you move your hip after hip replacement. See how it looks perfect and beautiful.
Robert A. Kayal, MD, FAAOS:So that's what we call the bearing surface. Now, in this model in particular, we're seeing this purplish color, lavender color ball, and that is an example of what we call a ceramic head. Ceramic heads are very commonly used in primary and revision total hip arthroplasty these days and in this particular model, this ceramic ball is articulating with a plastic polyethylene liner that's inserted into a titanium shell that is also inserted into the native acetabulum and in the femur or the thigh bone. You saw Dr Anda place a titanium stem, and this is what we call a total hip replacement. So, as we've discussed, total hip replacement surgery is an operation that is incredibly successful. It's really changed the lives of millions and millions of people across the world over the years. It is considered to be one of the most successful orthopedic operations performed.
Robert A. Kayal, MD, FAAOS:But, that being said, ultimately some patients require a revision. Dr Anda already discussed some of the common reasons for revision total hip replacement, including, but not limited to, loosening, instability and infection. Those are probably the three most common reasons for failure of total hip arthroplasty and need for revision surgery. So let's try to focus on this very complicated topic but communicated to you in layman's terms so it's fairly simple to understand when something might be wrong with your hip replacement and when you need to consult an orthopedic specialist like Dr Anda to get your total hip replacement evaluated. So, dr Anda, let's first talk about when we perform primary total hip arthroplasty what is typical for routine follow up for a hip replacement?
Gerald Andah, MD:So for follow up after a total hip replacement, first time we see the patients at two weeks, next time is six weeks, three months, six months one year and then each year we see them at least once after that, and the reason that we do that is to make sure that we're not missing anything that could be happening down the line that could be potentially causing the patient an issue or pain.
Robert A. Kayal, MD, FAAOS:Yeah, I agree with that fully, because certainly when implants fail for whatever reason and they can, we wanna pick up on that early right.
Robert A. Kayal, MD, FAAOS:Earlier diagnosis is better. We have a tendency to nip things in the bud and address small problems with small solutions as opposed to big problems with big solutions, right. So that's very important to emphasize and I agree with that. Once a year after the first year, at least follow up and see your doctor again for a follow up visit. Let the doctor take some x-rays, check the wound, make sure there are no concerning issues.
Robert A. Kayal, MD, FAAOS:So many times after this very successful operation, patients think that they're done after the first year and we won't see them again for five years or 10 years, for whatever reason, for a different problem, because they think everything's great and I'm glad things are great. But the thing is they forget when I tell them you need to come back once a year for an x-ray because they're feeling so good. But it is important to emphasize once a year routine follow up with your orthopedic surgeon so that he or she can assess you and make sure the x-rays look good and there are no concerning findings. Yeah, absolutely so. That being said, dr Andrew, what are some of the concerning complaints that patients may report and maybe some of the concerning findings on physical exam and x-ray that makes us suspicious that maybe something might be beginning to fail?
Gerald Andah, MD:Yeah, so your discussion with the patient is probably the most important thing, because the patient knows their body really well and they're gonna tell you when something isn't necessarily right. So pain is probably the number one factor that leads us to think that there might be something going on persistent pain. And then sometimes patients can complain of instability in the sense of feeling like something is shifting or moving. That might be one reason to sort of pause and assess and see if something's going on. And then there's one thing called startup pain. Sometimes patients get what's called startup pain and to sort of explain that, that means that when you first get up from a seated position and you start walking, you might have some pain. As the implant starts to settle into a better region or a better location, that pain eases up. So that indicates that the implant might be loose.
Robert A. Kayal, MD, FAAOS:Yeah, when they start to weight bear, when they get up out of bed or get up out of a chair and start to weight bear, they immediately get that stiffness. Very often they complain of stiffness more than anything and that's that microscopic subsidence of the implant into a stable configuration. And if that is something that you're experiencing, you definitely need to see your orthopedic surgeon or one of us to get that assessed, because it's very, very important not to miss loosening of an implant. Absolutely so. That startup pain is a classic complaint and it's often associated, even more than pain, with stiffness.
Robert A. Kayal, MD, FAAOS:Patients say I'm stiff, I can't really walk immediately. I have to sort of stand up and hold on to something for a few seconds until I can get my bearings, and then they start walking and they're better. And, surprisingly, the more they walk on a loose implant, the better they feel, because, as they're continuing to walk through it and put their body weight through that construct, it is stabilizing the implant in the bone and, although that implant is loose, they feel better when they're walking on it. But that is something that you have to see your doctor about quickly. Yep, absolutely so. You mentioned startup pain, stiffness we talked about. What other signs and symptoms might they be concerned about if they have, for instance, an infection?
Gerald Andah, MD:Right, so things that you want to look for if you have an infection is redness around the incision area. If you have drainage after your total hip replacements, two weeks after surgery, that is something that's concerning and should be evaluated by your doctor, and so any sort of drainage after the two week mark is something that you should bring to the attention of your physician.
Robert A. Kayal, MD, FAAOS:Yeah, at the most two weeks. Some people even are getting concerned at five to seven days after surgery. So we don't like drainage from a wound after surgery. If a wound is draining you need to see your doctor to get that assessed to make sure there's no evidence of infection. But let's assume that this hip replacement was done six months ago. What are some of the concerning findings regarding infection at that?
Gerald Andah, MD:time. So redness pain is one of the big things, and so persistent pain at six months after a total hip replacement is something that should be worked up by your physician to make sure that you don't have an infection, and we can talk about how that's done a little bit later.
Robert A. Kayal, MD, FAAOS:So look, it's one of the most rewarding operations. I've already alluded to that. Patients should only continue to get better after this operation, right? If patients start experiencing pain that's out of proportion to the surgery that was performed and if it does not seem to be dissipating or if it's heading in the wrong direction? Our training is that we always think of infection in our differential diagnosis. Right? Infection is called the great mimicar. It can present like anything. You don't have to have the classic signs of infection where the wound is opening up and draining pus or you're suffering with a fever and chills and persistent drainage from the wound. That always happened. When somebody is not progressing well after hip replacement surgery and the pain persists and they're just continuing to complain, it is incumbent upon us as physicians to work that patient up for infection and assume that it's infected until proven otherwise. So the work up for infection is critical in a joint that's not performing well. What else we talked about infection? We talked about startup pain and loosening. What about instability? How will patients present if they feel unstable?
Gerald Andah, MD:So patients that feel unstable usually present by saying that when they're either getting up from a seated position or doing anything that involves bending their hip, they feel like their hip is shifting. They feel a sensation of either the ball actually shifting or just coming out of the socket a little bit. That's what presents the most as instability.
Robert A. Kayal, MD, FAAOS:Yeah, and instability can be catastrophic for the patient. Instability can cause literally the joint to dislocate. When patients dislocate, they're miserable. The hip, the construct just completely dislocates. The ball falls out of the socket. The patients endure a significant deformity. Sometimes their sciatic nerves can be irritated or stretched during that traumatic event. Only the patients cannot weight bear on a hip construct that is unstable and dislocated. So instability can happen for a myriad of different reasons. What are some of those reasons that a hip can be?
Gerald Andah, MD:unstable. Probably one of the primary reasons that a hip can be unstable is if the tension in the muscles around the hip has not been adequately restored. There are different ways that you can restore the tension, but we have muscles around our hip, several different kinds of muscles. If the tendons that are attached to those muscles are not stretched out appropriately, that might allow the ball to pop out of the socket at some point after your hip replacement, exactly.
Robert A. Kayal, MD, FAAOS:That's critical to restore what we call the offset right. When we do total hip replacement surgery, our goal is to restore the proper offset or tension of the muscles and tendons that keep the hip stable. And again, the onus is on us to make sure that we restore that offset properly. And nowadays, especially at the Kale Orthopedic Center, when we employ the latest and greatest technologies with respect to designing patient-specific customized total hip replacement surgery using proprietary software and CAT scan technology where we do a virtual hip replacement on a computer, and then robotic technology to make sure we put it in accurately and precisely we're able to properly restore the patient's offset exactly how we want to restore that, so that the patients are stable and comfortable and their leg lengths are proper, and all that is very, very important to ensure a successful outcome for the patients after this procedure.
Robert A. Kayal, MD, FAAOS:So those are some of the most common reasons for need for hip replacement revision surgery, so let's talk about them a little bit in more detail. First and foremost, let's talk about infection. Okay, so we talked a little bit about the fact that patients can get infections early on and even later, right? What are some of the reasons for acute infections, infections that are occurring right after?
Gerald Andah, MD:surgery, for instance. So right after surgery, sometimes what we talked about drainage, because if there is fluid coming out of the wound, that means that there's a potential for bacteria to get into the wound. So that's probably one of the more common reasons for getting an infection in the acute period which is soon after your surgery.
Robert A. Kayal, MD, FAAOS:So that drainage can come from the surgery itself. It can come from blood thinners too, right it's? You know patients can get blood clots after joint replacement surgery or any orthopedic surgery or any surgery in general. But certainly joint replacement surgery does put patients at risk and some patients are at a higher risk than other patients Absolutely, and we have to put those patients on blood thinners. So it's sort of a catch-22, but we have to do it because we don't want our patients to get blood clots and pulmonary emboli. But if they do get placed on an aggressive blood thinner and they end up bleeding a little bit, that some of that blood can continue to drain out of the wound and that is something that can potentially predispose our patients and other patients for infection correct. So what other risk factors can increase the patient's risk?
Gerald Andah, MD:of infection. So sometimes some comorbidities that patients have, including diabetes, rheumatoid arthritis, things like that might put you at increased risk for getting an infection, and the reason that that happens is that when you have those conditions, it really decreases your body's ability to fight off bacteria and puts you at higher risk for getting an infection, and some of the risks that have a higher body mass index are also at risk for getting an infection for the same reasons, certainly, and smokers too.
Robert A. Kayal, MD, FAAOS:Right, and smokers, yeah, People that smoke. It definitely deleteriously affects your circulation and increases the risk of infection. Smokers commonly occur from primarily a few different sources. Right, One of those sources can be our own body. Right, Because our skin is a barrier to infection and there are a lot of organisms that live on our skin. Right, so some of those most common infections are staff right and our bodies have staff epidermis, for instance, all over it. Staff aureus is a very common infection. People can get infections from other infections in other areas of their body. If they have an upper respiratory tract infection or a urinary tract infection, a dental infection, these bacteria can get into the bloodstream and then ultimately circulate to the joint and infect your implant as well.
Gerald Andah, MD:Yeah, and you know, one of the other things I'm glad you brought that up is because we have a lot of bacteria, like you said, on our skin, in our gut and also in our mouth, right and so it is important that you let your physician know after you have a total hip or a total near placement when you're getting dental work done, because you're going to need to have antibiotics before you get the dental work, so that whatever bacteria is in your mouth does not spread through your blood to your implant.
Robert A. Kayal, MD, FAAOS:Right. So infection is a devastating complication and you know the onus is on us, but also the patient, to take measures to minimize the risk of infection. First of all, with respect to us, what can we do besides sending our patients to the dentist, if necessary, addressing their dental carries before surgery, making sure that they don't have any other active infections in their body when we do the joint replacement, like dental infections or urinary tract infections or others? We can also do things to the skin right to decolonize our patients, right? Yeah, speak about that for us if you can.
Gerald Andah, MD:So some of our pre-surgery routine involves reducing the amount of bacteria that you have on your skin and in other parts of your body. So we routinely have patients get a what's called a hibiclens wipe, which is a special kind of solution that kills bacteria, and we have patients wipe the surgical site for five days prior to surgery, whether you're getting a hip or knee replacement. We also have patients use an ointment that kills bacteria that can live inside your nose. It's actually pretty harmful bacteria for the same amount of time prior to surgery to help reduce that risk of that bacteria getting to the implant that we put in.
Robert A. Kayal, MD, FAAOS:That's the back to the band or the mute person ointment correct? Yeah, so we take some measures to optimize our patients for surgery, but I think it's important for the patients also to take some responsibility, because we're doing this operation together. Absolutely, we strongly believe that we're going to live up to our expectations and take responsibility. But it's important for patients to participate in their care as well, which means to optimize their medical health and nutrition status and weight prior to their joint replacement surgery. Absolutely, some patients suffer from diabetes mellitus and their hemoglobin A1C is high. It's poorly controlled. We recognize that through blood work et cetera. But then we want the patients to participate to minimize the risk of infection by getting their diabetes under control. Yeah, or we ask them to stop smoking. Or if they're an autoimmune patient that happens to be on some medications that can increase the risk of infection, we ask them to consult with the rheumatologist or their primary care doctor to minimize the usage of certain medications like steroids, before the surgery which can compromise wound healing after surgery. So I think it's important to mention all those things because we can work as a team with our patients to really decrease that risk of periproesthetic infection.
Robert A. Kayal, MD, FAAOS:As far as the other common source of revision hip replacement loosening. We discussed loosening and then we talked about two different types of loosening. For the most part there is aseptic loosening and septic loosening. Well, septic loosening would be secondary to that infection where the bacteria invade and start to eat away the bone and loosen the construct, and that's a devastating complication, clearly. But let's talk a little bit about aseptic loosening, or loosening that can occur without infection Right.
Gerald Andah, MD:So loosening that can occur without infection can happen for a couple reasons. Probably one of the more simple reasons is if the implant that's put in at the time of surgery is too small. Sometimes that has the ability to loosen because it doesn't grab the bone as well. One of the other reasons that you can get loosening in your implant is sometimes there are small particles that are released from the materials itself in the hip over time that the body starts to try to fight and in your body's attempt to fight these particles it can eat away at some of the healthy bone. Sometimes, when that happens, that allows the implants to loosen over time. So those are probably the two, I would say, most common reasons why you get aseptic or loosening from no infection.
Robert A. Kayal, MD, FAAOS:Yeah, and just to further elaborate on what Dr Ando was mentioning, there's the concept of particulate debris that we're talking about here, where there's debris that's formed due to repetitive microscopic motion between parts of the implant. You can see, based on the visual that we presented to you earlier, that these total hip constructs are modular constructs. They're not what we call monoblocks, they're modular. The pieces are interchangeable. You have different stem sizes, you have different ball sizes, you have different cup sizes, you have different polyethylene liner sizes, and when you snap on one piece to another, there tends to be some type of lock or tape or fit that secures that implant in place for life, hopefully. But over the years, after loading this implant, millions and millions and millions of cycles, there can be some microscopic wear between the bearing surfaces and between the articulations between these modular components, and some of that wear can be plastic wear and some of the wear can be metal articulating with metal wear. But what Dr Ando was mentioning was that this wear, this part what we call particulate debris incites some type of autoimmune inflammatory response where our body's immune system attacks that debris and, unfortunately, in its efforts to rid ourselves of that debris, it often can cause what we call osteolysis and loosening of the implant.
Robert A. Kayal, MD, FAAOS:It can erode and eat up some of the bone and cause implants to fail. It causes some types of reactions sometimes, especially the metal on metal types of articulations can cause some adverse soft tissue reactions which can cause very, very devastating effects to the soft tissues, which can cause loosening and instability and failure of the construct. So that is another potential source of failure of total hip replacement. If these things are not picked up. And this really reinforces my recommendation to make sure that you see a doctor at least once a year after your hip replacement to make sure that there are no signs on physical exam or on radiographs that would suggest potentially that any of these things is occurring Absolutely. Also, we talked about another source of failure which, besides loosening, besides infection, we talked about instability as well. But how about leg length inequality? Is that potentially a problem after hip replacement?
Gerald Andah, MD:surgery as well 100%, and so one of the other reasons that patients get instability is when they don't have their leg lengths restored to its natural anatomy, and what that does is that goes back to the point that we made earlier, where it doesn't restore the correct amount of tension to the muscles that are attached to your hip, and so it makes your hip loose in a sense. So if your leg is short by a few millimeters, that reduces the amount of tension that the muscles or tendons around your hip have and it reduces their ability to hold the ball in the socket, and then that's when you can dislocate, which is a very traumatic event that we sort of spoke about.
Robert A. Kayal, MD, FAAOS:Yeah, and we're talking about all these complications only because we're talking about the topic of revision hip replacement surgery. But I think it's important to emphasize that, like I said earlier in the podcast, total hip replacement surgery is probably the most successful operation performed in our field, absolutely. There are incredible, incredible outcomes and long-term outcomes. That is as well, and these complications that we're discussing are incredibly uncommon. They can occur, but they're exceedingly uncommon. But I think it's important to talk about it, just so the patients know that these things exist and, if they're suffering from any of these complications, that we do have solutions for these problems. And that's what we're here for today To bring this information to you so that you can find hope, if you're suffering from some of these complications, that we have solutions at the Kale Orthopedic Center.
Robert A. Kayal, MD, FAAOS:So let's talk about some of these solutions, because I know you gave us a beautiful demonstration of how a primary total hip replacement gets performed. But when these things happen, there has to be a solution to restore that patient's quality of life and function. So let's talk about them specifically. If there is an infection and that implant is now infected, let's make believe that that surgery was done recently. The patient's still draining two weeks after total hip replacement surgery, maybe three weeks at the most. Hopefully he didn't wait that long. Just had the operation. The wound is still draining.
Gerald Andah, MD:What are you going to do so? First thing we do is work up an infection. We do some of the ways that we do that, obviously with imaging and lab work. So blood tests there are specific blood tests that assess your body's level of inflammation, which is a sign of infection. If those markers are high, then we depending on how recent your surgery was, we either automatically take you back to the operating room or we take some fluid out of the joint If we're talking about hips right now so out of the hip joint and send that to the lab to see if it grows bacteria or has certain markers that indicate an infection.
Gerald Andah, MD:Once that's done, if you've had your surgery in the acute period, which is within a few weeks, then you can go back to the operating room and take out the replaceable parts of the hip. So there are some parts of your hip the socket part and the stem that take a lot more work to replace. There are parts like the ball and the liner that can be replaced pretty easily. So in those situations where you have an acute spread of an infection that came from dental work or a UTI or an upper respiratory tract infection or something of that sort, the key is to be really aggressive and attack it really quickly. So we want to take those patients back to the operating room as soon as possible to try to save the implant, and so the real key in a situation like that is getting them to the operating room as soon as possible to get that treated.
Robert A. Kayal, MD, FAAOS:Yeah. So I think it's so important for patients to understand. If you have a total hip replacement that was just done and is still draining to seven to 10 days after surgery two weeks after surgery more than likely you're going to have to get that hip washed out, cleaned up and that hip will more than likely be able to be salvaged with that simple little washout. If you have a hip replacement that was functioning well for many, many, many years and then all of a sudden you get an infection in your body somewhere or have a dental procedure or have an abscess in your mouth or have a urinary tract infection, an ear infection, upper respiratory tract infection, and then suddenly, a couple weeks later, your previously well functioning hip all of a sudden starts bothering you tremendously, there is a concern that maybe some of the infection got into the blood and then subsequently infected your well functioning total hip. In that particular case, again, you're going to have to get that hip washed out quickly. Time is of the essence. See your doctor, let them assess you and you may need to get that hip washed out.
Robert A. Kayal, MD, FAAOS:If it is determined that you suffered from what's called an acute hematogenous spread to a well functioning hip replacement, then there's the patient that had a hip replacement that was never, ever, ever satisfied after their hip replacement continuing to deteriorate, never satisfied, persistent pain, maybe startup pain, maybe evidence of loosening osteolysis. On x-ray More than likely that patient was suffering from a chronic infection all the way dating back to the beginning and that's a chronic infection. That implant cannot be saved. If it is determined that that patient is suffering from a chronic infection of that implant, that patient is going to have to have that implant taken out, an antibiotic impregnated spacer put in. That patient will need to be treated with antibiotics for a minimum of six weeks IV and then only after that chronic infection is cleaned up fully can your surgeon go back and reinstall a new total hip replacement.
Robert A. Kayal, MD, FAAOS:Is there anything else you want to add to that?
Gerald Andah, MD:Yeah, you know, the reason that we distinguish between having an acute infection and having a chronic infection is because of how bacteria behave. So I'm not going to get into too much detail. But the bacteria create a little cover around the implant if you give them enough time. So the reason we try to get to these acute infections quickly is so that we don't allow the bacteria to do that. But if you have a chronic infection, like you were just saying, if this has been going on for months and months or it never felt right, then most likely the bacteria has already created that cover, that film, that antibiotics cannot penetrate.
Robert A. Kayal, MD, FAAOS:I think that's a great point and I'm so glad you brought that up because it's so important to emphasize that. What he's talking about is this cover or lining that we call a glycocalyx. It's an impenetrable sheath around the infection that is often impenetrable to IV antibiotics and it definitely requires a very, very aggressive debris month to get rid of those bacterial infections and sometimes removal of the implant itself. So time is always of the essence with infection, because some literature says that, you know, these bacteria can form these impenetrable glycocalyxies within a day or so hours after infections. So it's so important when you're experiencing symptoms of infection pain, persistent pain heading in the wrong direction, loosening, instability see your doctor and let us make sure that you're not suffering from a complication. So now that we've talked about loosening an infection and instability, leg length, inequality and certainly other things can go wrong too.
Robert A. Kayal, MD, FAAOS:Right, if somebody has a hip replacement, someone can fall and suffer a serious fracture around a hip replacement. You could break your thigh bone, your femur, even without a hip replacement. But if you break it around a hip replacement, that would require sometimes a revision, total hip replacement. So in all of these scenarios that we've outlined, where there's loosening, infection, instability, leg length, inequality and certainly fracture and infection. Sometimes these patients have to undergo a revision total hip replacement. So we've demonstrated earlier in this podcast how a primary total hip replacement gets performed. But now you're dealing with a revision and in a revision scenario you're already missing bone In a primary total joint. All the bone is there, so it's certainly much more easy to perform a primary total hip replacement. What do you do with a revision when there's bone loss? How do you do a hip replacement if you're missing bone?
Gerald Andah, MD:It's actually really interesting. This right here is a primary total hip replacement stem. So you can see how it's wide at the top and gets really skinny down here, because it gets most of its fixation in the top part of the bone. This because there's good bone there. Exactly, this is a revision stem and you can see how it's much longer in the primary stem because this gets its fixation lower down in the bone. And that happens because when you're in the situation where you have to do a revision total hip replacement, the top part of the bone is compromised and the quality of the bone is usually not that good, and so now you have to go a level lower to get good fixation. So that's why these revision implants look so long, because they get their fixation in the bottom half of the bone.
Robert A. Kayal, MD, FAAOS:Yeah, the bottom half of the bone we call the diaphysis, or the shaft of the bone right. The top part of the bone we call the metaphysis, and in the primary hip replacement we typically get what's called metaphysial fixation because there's good bone there. But in the revision scenario it's very much compromised for the reasons we talked about. It can be infected, it could be horrible bone, it can be an area of what we call osteolysis for many different reasons where the bone gets eaten up and destroyed and you can't rely on fixing a revision hip replacement most of the time in the metaphysis Right so we have to obtain what's called diaphysial fixation and if you can just show us those stems again, with diaphysial fixation we're dealing typically with those tapered, fluted stems right so, and they're coated circumferentially.
Robert A. Kayal, MD, FAAOS:So let's show all that compared to the primary hip replacement that is coated approximately in the metaphysis, as you can see here in Dr Ando's left hand you see that primary total hip coated strictly in the metaphysis. That's where the bone in growth and fixation takes place. It's what's called a tapered stem and you get great fixation in that metaphysial region in the virgin native femur. But in the revised femur in his right hand there's no good bone approximately. So he's demonstrating this long tapered fluted stem that's coated circumferentially.
Gerald Andah, MD:That will allow bone to grow into all of that circumferentially, and the fluted stem will also provide a lot of rotational stability as well, yeah, and so you can see how the primary stem is thick at the top right and thin at the bottom Because, again, we're focusing most of our fixation at the top. But you can see in the revision stem it's pretty cylindrical all the way down and it's much thicker at the bottom half than you have in a primary stem.
Robert A. Kayal, MD, FAAOS:So the way these implants get installed. We have to prepare the canals right With the primary total hip. We tend to use broaches and then get a nice tight fit and in the revision scenario we'll often ream right. We'll ream the canal to a certain diameter a tapered reamer and really get a really nice purchase in that diaphysis and we get a well fixed diaphysial engagement stem. Now let's focus our attention in the revision scenario now on the cup. What can happen in the cup and how do we address these issues with bone loss in the acetabulum?
Gerald Andah, MD:So this is your acetabulum. Normally, in a revision situation, there is some amount of bone loss around the acetabulum. What we rely on for fixation in a primary hip replacement is these columns. So if there is a revision situation in which either the infection has eaten up the bone or there is osteolysis from where particles for some other reason, sometimes there's no longer this support and so you need there are different. There are a few different kinds of implants that you can use. Most of them are geared towards getting some sort of alternate stability in instead of getting that press fit fixation between these two columns. So that can involve using screws. That can involve using constructs called a cup cage. That can involve using custom implants that are actually made specific per patient based on the amount of bone that's lost, called custom triflinges, and they're all geared towards getting screws and fixation in different parts of the bone other than the bone that's lost Right.
Robert A. Kayal, MD, FAAOS:Fortunately though, however, most of the time patients can just get away with the doctor performing a revision of the cup right by just putting in a bigger cup, you know, just reaming the acetabulum a little bit more and putting a bigger cup, and it's probably the most common technique employed in the failure of the acetabulum a revision, total hip arthroplasty that affects the acetabulum. But you know what about with instability? When there's instability, what types of things can be done to address that, whether it's, you know, changing the ball or changing offset stems, what can be done if a patient is just feeling unstable?
Gerald Andah, MD:Yeah, so there are two things that really affect your stability. That's one we've talked about offset a couple of times already, and your leg lengths, and so usually if your hip is unstable, one of those two things needs to be addressed. So at the time of the revision surgery, you can go in and increase the ball size, which is going to increase your leg length, or increase the amount of offset that you have, which is increasing the tension on that, on those muscles and structures around the hip, so that you're putting in the hip tighter so it doesn't pop out Right.
Robert A. Kayal, MD, FAAOS:Well, fortunately, because these are modular hip replacements, as long as your surgeon can identify what the problem is and very often we can based on x-rays alone, but sometimes we'll employ MRI imaging technology or CAT scan imaging technology. Fortunately, because there are modular implants, we have so many different options to address each patient's concern on a case-by-case basis. Sometimes that will entail us revising all components in the total hip replacement and very often we can get away with just changing one component or two components, like the size of the head or the plastic liner. Sometimes we have to change the stem, sometimes we have to change the cup, but it really depends on what the patient's problem is, and that's often very easily identified and we treat each patient as an individual and on a case-by-case basis, we address them that way. Correct, absolutely.
Robert A. Kayal, MD, FAAOS:So sometimes even revisions can be performed in a very minimally invasive manner, 100%, yeah, so this is probably, I think we nailed, the most common important issues to talk about with patients when it comes to implants that have failed and require revisions. And, by the way, when we say a failed total hip, it doesn't necessarily mean that your surgeon did anything wrong. These are just mechanical constructs that can fail over time or certain things are out of surgeon's control, like infection and patient comorbidities, but in general we call it a failed total hip, when a total hip replacement has failed over time for whatever reason. And what would you say is the important take-home message to our viewing audience and our listeners that they should just remember after this podcast if they're suffering from some issues pertaining to their total hip replacement.
Gerald Andah, MD:I would say the most important message is to communicate with your physician, right? I would say the most important message is to let them know how you're feeling, so that if something is actually wrong, it can be worked up.
Robert A. Kayal, MD, FAAOS:Yeah, I mean because common things are common and uncommon things are uncommon, and certainly when you say those buzzwords to us, we immediately start thinking of things in a differential diagnosis, because we know what complaints are concerning and which ones are normal. So I think it's very important to communicate exactly how you're feeling to your doctor, and the only other thing I'd like to add to that is that regular follow-up is so important, regardless of how you feel, because an orthopedic surgeon can look at an x-ray and a million things can go through our minds. Based on the results of an x-ray, we know if something looks perfect or if something's beginning to suggest that there's early wear, early loosening or a problem that's developing. And certainly just by talking to us, just by talking to us we can start tabulating a differential diagnosis in our mind based on some of the buzzwords that you may or may not be saying to us. We want to know that you're doing well, we want to know that there are no problems, but if there are problems, we want to know about it.
Robert A. Kayal, MD, FAAOS:The sooner the better. Right, absolutely All right. So thank you so much for spending some time with me, dr Andan, to help us communicate to our patients about hip replacements and problems that can occur with hip replacements and the need to see a specialist like Dr Anda, who's always readily available and happy to see you at any time. So feel free to reach out. Thanks so much, dr Andan.
Gerald Andah, MD:It was a pleasure. Thank you for having me. Thanks for your time.
Robert A. Kayal, MD, FAAOS:All right.
