Dr Savyasachi Thakkar, discusses the relationship between the spine and pelvis.
Good evening everybody and welcome all of you to the 66th live webinar on our three principles and good morning to all those who are watching it from the United States. Today we have guests of honor. Dr Sylvia sake are simply called salvia Docker. From john Hopkins Baltimore, United States. Dr tucker is a hip and knee reconstructive surgeon serving patients in Baltimore Maryland and Washington D. C. Metro areas. This expedites is mainly on minimally invasive hip and knee surgery including partial and total hip and knee replacements, outpatient joint replacement and complex televisions. After previous joint replacement surgery, the attacker uses computer and robotic assisted techniques for these procedures to provide cutting edge care to patients with hip and knee arthritis. Currently, he serves as assistant professor of orthopedic surgery at johns Hopkins Dr Karev completed his medical degree at johns Hopkins University School of Medicine and stayed for his residency again at john Hopkins, it was the first recipient of the Donald Young leadership award as chief resident. He continued his training as a knee arthritis and rheumatology fellow in Switzerland, followed by an adult reconstruction fellowship in new york. He then pursued the procedures, european New society traveling fellowship focusing on nuance surgical techniques and management of arthritis. The doctor's research interests include technological advances in the treatment of arthritis. Posttraumatic arthritis. The economic impact of arthritis and the optimization of hospital protocols for arthritis management. He's also interested in exploring same day john recent search. Yes, mice time in the hospital maximize return to function. So today it's my great honor to introduce you to dr Samuels sochi tucker over to you dr tucker. Thank you very much. Doctor Gopalan for including me in this dynamic lecture series which and we're going to talk this morning uh in morning in Washington D. C. But evening in India. So good evening to everyone who's joining us in India on the spine pelvis relationship, especially from the perspective of a hip surgeon. Um and this is a this is a fairly complex topic that's gaining a lot of traction and I was hoping that we could cover some basic principles. Mhm. I have no relevant disclosures for this talk but this is our beautiful hospital in Baltimore the johns Hopkins hospital. And I'm very privileged to be a part of the orthopedics department there and I welcome whoever would like to come and visit us. So you know when we think about the spine and pelvis relationship we have to kind of go to the proverbial chicken and the egg. What came first? Was it the chicken or the egg or vice versa. And I invite you to think about a paradigm shift. We really have to think about the egg as a boneless chicken. So we have to combine these principles to really understand how the spine affects the pelvis and vice versa and we have to work together with our spine surgery, colleagues sometimes too appropriately placed implants in these patients to prevent complications and I'll go over some of these complications in some of my later slides. the sacrum pelvis junction is a very complex junction because it's the link between the actual skeleton which is the spine and then the appendix killer skeleton which is the pelvis and the lower extremities. So changes in one frequently affect the other. And it's a very dynamic relationship as highlighted by this video which was developed in leon France. So in this uh you know, you can see that the sacrament will be attached to the spinal column. As you can see here in the spinal column is a very mobile unit with multiple joints. Across the spectrum. There is a sacred slope which then defines where the spine and pelvis lie. Uh and as the sacrum moves in the saddle playing video, you can see how the spinal curvature are changing. Now switching to the corona view as the sacred moves side to side. Once again, the spinal curves have to compensate for the sacred, the sacrum, fortunately or unfortunately is attached to the pelvis. So now as the pelvis moves side to side again, the spinal columns have to adjust in a compensatory fashion. And this relationship also exists in the sagittal plane. So this is a complex three dimensional relationship in terms of spinal sagittal and spinal pelvic balance. So today, what we're going to do is we're going to look at some spinal pelvic measurements. I will start by defining these measurements with regards to a spine surgeon. And then I'll take it with regards to a total hip surgeon because we have similar nomenclature. But we look at this from two different perspectives. So it's like two sides of a coin. Then we will define what exactly is the meaning of assad tabular anti version as it means to the spine surgeon and as it means to the total hip surgeon, then we will look at some examples of sagittal spinal balance and imbalance. And finally we will discuss the implications for total hip and I will demonstrate three cases to go over some of these principles. So these are the three critical spinal pelvic measurements that we all need to understand and most of the times these are used by spine surgeons to define balance or imbalance. But even as hip surgeons, we should at least understand the basic principles. The first one is a sacred slope, then we have the pelvic tilt and the pelvic incidents. The pelvic incidents from amongst these is constant and any changes that happen. Keep the pelvic incidents constant, but changes will be in the sacred slope and the pelvic tilt. So let's define these. The sacral slope is defined as a line drawn from the top of the sacrum along and an a line drawn horizontal and the angle that is formed by these two lions is defined as the sacral slope and this is where the sacrum meets the lumbar spine and defines that junction pelvic tilt is defined by a line drawn vertically north or vertically towards the head from the center of the femoral head in the sagittal plane, and another line drawn from the center of the femoral head to the center of the top of the sacrum, the sacrum, the approximate aspect of the sacrum, and that angle is known as the pelvic tilt. Finally, pelvic incidents is a line drawn from the center of the femoral head in the sagittal plane to the center of the proximal aspect of the sacrum, and another line drawn along the sacral body. So this value is what remains constant. Now, if you look at this, the pelvic incidents. Once again, I'm going to draw it out for you. It's the line down the body of the sacrum and connecting it to the femoral head from the center of the circle the pelvic tilt, as you can see here is the line connected by the center of the sacrum to the center of the femoral head, and then one drawn vertically north towards the head, and finally the sacral slope is a horizontal line to the slope of the proximal aspect of the sacrum. As you can see the relationship of this is that the pelvic incidence equals to the pelvic tilt plus the sacral slope. So it's the sum of the pelvic tilt plus the sacral slope Pelvic incidents averages about 50°. So the ranges from about 48 to 53°, and it's fixed in adults and Children, it's still moving, but in adults it's fixed. So any kind of compensatory movements have to happen by alterations in sacral slope and pelvic tilt. But we don't really understand these when we're doing a total hip. So let's define this further. Now, what is the relationship between the spine and pelvis and what's considered balanced and unbalanced? So Schwab looked at this and published this in 2013. For this we have to measure the cobb angle for Lombard or large doses. So you take L. One and you take L. Five and you draw lines along the superior aspect of L. One and the inferior aspect of L. Five. And then you draw perpendicular lines. And the angle that is connected by these are made by these perpendicular lines is called lumbar lower doses. So ideally the lumbar fluorosis should be within 10 degrees of the pelvic incident. So the ideal sacral ideal sagittal balance is when you have a pelvic tilt that's lower than 22 degrees and the mismatch between the pelvic incidents and lumbar fluorosis Is less than 10 or 11°. So that's when you know that the spine is well balanced. And this is an example of spinal pelvic mismatch, where the lumbar low doses in this case is approximately 22 degrees by the cobb angle technique And the Pelvic incidence is shown to be 65°. So there is a greater than 10° mismatch. And this is typical of a flat back syndrome where adequate lumbar low doses has not been restored in the fusion construct for this patient. Now those were the spine terms, but we have to really look at terms for the asset pabulum and terms for the pelvis. So now let's switch our roles from spine surgeons to hip surgeons. And we have to look at ASU tabular anti version. Asi tabular anti version can be defined in several different planes. And I have, you know, a pelvis model with an acid pabulum fixed into it. So if you're doing a poster or lateral approach which I tend to use for a lot of my cases, you look at ASU tabular anti version in the sagittal plane, especially when you position a patient and when you see what is the opening angle of the cup. If you look at a radiograph to assess how much anti version you have, you will look at it in a Corolla in plain by holding the purpose like this. If you are going to assess failure of acid tabular components and see whether or not there was enough anti version, you will get a cross table lateral x ray for these patients to see whether as a tabular anti version was restored or you will get a transport plane ct scan or or a cross sectional ct scan and you'll see where does the cup point does it point towards the head or towards the ceiling, which is anti averted or does it point towards the floor, which means retro version. So for the purposes of this talk, we are really going to focus on sagittal spinal issues and satchel spinal balance. And that will be defined as our operative as a tabular anti version. So how do we measure that? We will draw a line from the posterior inferior aspect of the asset pabulum parallel to the floor, so that's your horizontal reference. And then we draw another lion connecting the post superior inferior aspect of the ashtabula um to the anterior superior aspect of the established and that's defined as a set tabular anti version. And you can see that is pointed towards the front. Now these are examples of what happens when you go from a standing position shown on the left to a sitting position, shown on the right. So notice in both these figures, what's key to notice is that the pelvic incidents remains absolutely the same. Look at the sacral slope from the standing position to the sitting position, the sacral slope decreases. So if the pelvic incidents has to remain constant, What has to happen is that the pelvic tilt has to increase from the standing position to the sitting position along with an increase in the pelvic tilt. There is also an increase in the acid tabular anti version. Now this is a case of a normal person who doesn't have any spinal pathology or a prior spinal fusion. So this is a flexible spinal pelvic unit and to illustrate this with this model. If you're in a standing position, that's how the pelvis appears and in a sitting position. That's what happens if you want to look at it in terms of the acid pabulum that I have fixed in a standing position. Your acid tabular component is somewhat like this in a sitting position. The acid tabular component appears to be more anti vertical and more vertical. So let's look at that was pelvic um changes from the standing to the sitting. What about pelvic version? Pelvic anti version And retro version is a little bit different than acid tabular anti version. And retro version. And I have a wonderful video again shortly on showing this. So tilting the pelvis forward as if to give an intellect view of the pelvis is known as pelvic anti version. Okay, now let's I'm just focusing on the pelvis and the slide even though there are some compensatory changes in the spine on how the spine is stressed. If the pelvis is moved backwards posterior early so that it gives an outlet view of the pelvis or an X ray or any p pelvis X ray that is known as pelvic retro version. So once again I'm going to demonstrate this with my pelvic model. So if I'm looking at the pelvis straight on a corona plane, this is called pelvic anti version and intellect view of the pelvis and this is called pelvic retro version. Okay, but notice what happens in the sagittal plane as I do that. So the sagittal plane, I'm holding the pelvis in pelvic anti version. You can see inside the pelvis. Look at the acid tabular component. The acid tabular component actually appears to be. If you look at an ap view it appears to be very neutral or retro averted. So the asset pabulum is retro averted. Now if the pelvis goes into a retro version, so that's an outlet view. As seen here, look at how much opening you see in the acid fabulous. So now the acid tabular anti version is exaggerated. So how do you define this paradoxical relationship? And this is a simple slide to conceptualize it as you are standing. So this is your pelvis model again, as you are standing, if you have normal Lord doses, you tend to have pelvic anti version. And with pelvic anti version, the acid tabular anti version is reduced. So there is relative retro version of the asa tabulation in relation to the pelvis. As you sit down your pelvis goes into retro version. So you have an outlet view of the pelvis but the acid tabular anti version and verticality increase. So it's a paradoxical relationship between the pelvis and the assad tabular and that is key to understand the spinal pelvic palace. What do you put the cup and this is a video again kind of demonstrating standing to sitting position As you go from standing to sitting? The acid tabular anti version as we discovered in the previous slides increases. The average increase in a normal patient is about 15 or 16°. Along with this, you have to understand that the cup verticality also increases by about 20 or 25°. And this is very important as you are placing aside tabular components. If you place an ashtabula component appropriately and diverted your cup is going to be slightly vertical and as you over and divert this. In some of these cases, you have to be careful that you do not make your cup to vertical. That is just the three dimensional nature of the answer to be So, the corollary to that is that if you are placing your ashtabula component in retro version, the asset tabular component will be a lot more horizontal. So just be aware of this as you perform your total hip cases and pay attention to this three dimensional relationship. No pelvic, you know, when you use these sagittal plane references that we define which is the sacral slope, pelvic tilt, pelvic incidents, lumbar scoliosis, What is important to realize that as you do a total hip, you know, really the pelvic tilt does not change the sacred slope does not change the pelvic incidents does not change. What changes is the position of the patient when they go from a standing to a sitting position. So the pelvic tilt and the pelvic incidents and sacral slope will remain the same as you're doing a total hip. But what changes are these parameters as the patient mobilizes? So a safe zone that has been determined lunatics. Safe zone is about 5-25° of anti version. And if you're doing the Inuit combined anti version technique, you should have about between 30 degrees to 50 degrees of combined anti version. And the concept of combined anti version is very confusing. So I have a I have a slide showing you this and this is from rana. What's publication. What you do is that with the leg in a neutral position from post unilateral approach. You line up the flag part of the trial head with the flat part of the polyethylene. So you make them parallel or co planer with the leg in the neutral position. Now the second thing you do is that you look at the angle made between the leg so that's between the tibia fibula and the floor. And that angle should be anywhere between 30 and 50°. If you've had a good anti version in the cup and good anti version in your step. So that angle should be between 30 and 50°. In most cases you may have to over exaggerate this in some of the spinal pelvic imbalance cases that I'll show you. But it's important to understand that this is a check and a balance intra operatively and it's a very useful tool to align your components. So again let's kind of expand on this concept. Where do you put the cup With one degree changes in pelvic tilt? There is about not a complete degree but about .8° change in asset tabular anti version. So as the pelvic tilt increases there is an increase in passive tabular anti version and vice versa with an increase in pelvic retro version. Now against pelvic retro version as you remember is the sitting position where you get more of an outlet view with pelvic retro version there is an increase in asset tabular anti virtual with pelvic anti virgin there is a decrease in and as a tabular anti version. Okay um in a total hip without spinal deformity correction. The biggest problem is a high dislocation rate. So we have to be very cognizant of this in terms of our spinal pelvic ballots. This is the absolute key principles. So today if you're going to walk away with anything in this talk I think you have to understand the balance of the spine on the pelvis and the pelvis further down and here is a beautiful slide illustrating this um The Spinal Pelvic unit is fixed but when the Pelvis six on something it's the femoral head and there are several degrees of rotation between the pelvis and the federal head. So this this unit as you see here is very mobile in multiple different planes and it is very unstable. So what is the principle that's important in this? Well the principle is that if your spinal pelvic unit is imbalance, unfortunately what is going to take bear? The brunt of this is going to be your hip. So you'll have hip arthritis secondary to that when you do a total hip in these patients that implant is going to be stressed a lot more and the risk of polyethylene wear bearing surface failure. And this location is very, very high. And it's because of this, the pelvis is rotating very freely around the femoral heads. Now of course there are muscles and capsule or attachments that stabilizes. But overall the least stable place is at the joint which is the hip joint. So what's the treatment algorithm? Well, in some ways this is my treatment algorithm. But some of the literature is proving this to be a little old and a little too simplistic and I'll go over this further on. So if possible you can get these films called the EOS films, it's a proprietary software and proprietary hardware in which you get sagittal standing and sitting spine films. And I'll show you some examples and if possible if there's spinal pelvic imbalance, do a spine fusion and then put your hips in the uh adequate position so that you're narrowing your zone of air or you're narrowing your margin of error and where where to put the vegetable component And there is a classification to understand spinal pelvic balance or imbalance. So this is the example of this ecosystem. It's a proprietary system and it's pretty expensive but some institutes have it and you can get a very nice view of how the spinal column lines up with the pelvic column and then how the lower extremely lines up and where the forces are in this model. Now what is the spine balance classification is very simple. It's a four by four or a story or two by two planets square. Um Most of us will belong in the top left which is we have a flexible and balanced spine if we are not fortunate. Um and we have to undergo spinal fusion procedures, especially spinal pelvic fusion, we would like to be in the top right, which is a rigid but balanced spine. If we have adult spinal deformity, we mostly tend to be in a flexible and unbalanced spine. So in the bottom left and from the bottom left, if we have to go somewhere, we really want to go to the top right, we want to be rigid and we want to be balanced. But sometimes because of issues with interpretive concerns or because of inadequate correction of the spinal deformity. We end up in the bottom right, which is the rigid unbalanced category which is the most dangerous for these conditions. So again we have looked at this before what happens in the flexible yet balanced spine. You go from a standing position that looks like this to a sitting position that looks like that. So there is an increase in the pelvic tilt as you sit down. There is an increase in the pelvic retro version as you sit down and your cup Anti version and your cup inclination tends to increase. But there is a low risk of independent in these cases uh if you put your total hip tabular component between five and 25° of anti version. So this is the ideal circumstance for the hip surgeon. You can put the cup in romantic safe zone and for the most part you will be okay. What happens in a rigid but balanced spine. So now what is happening is that you have hardware up in the spine and you are fixing the lumbar column to the pelvis by means of Lambeau sacra or sacra pelvic fixation. So now what happens is that depending on where you have been fixed and ideally you've been fixed with a lumbar low doses pelvic incidents mismatch of less than 11°. This is not going to happen. You're not going to go from this position to this position as you go from standing to sitting, you're kind of fixed in this in between position. So there is no compensatory increase in pelvic tilt. There is no compensatory increase in asset tabular anti version. There is no compensatory increase in pelvic retro version. So if you are in this relatively neutral position for the acid ambulance, when you sit you will impinge anti really and buy in pinching auntie really you will tend to leave her out for serially. So in that situation you have to as a hip surgeon give the asset pabulum more anti version. And this has been shown in this figure here where the extreme right picture. You see where the impingement occurs with the asterix and you would want to put the cup in greater anti versions about 15-25° of anti version. So that you give them the most likely benefit of preventing anterior impingement and posterior dislocation. And you're also by giving them as a tabular you know you're increasingly anti version and I'm exaggerating in this case you're also increasing posterior coverage for these patients. Now what happens is a flexible but an unbalanced spine. So in a flexible but an unbalanced spine most likely you are reducing your lumbar fluorosis. You have flat back. Okay? So in the flat back uh you know your your pelvic retro version already exists and to compensate for that pelvic retro version, most patients will lean forward so they will have a positive sagittal imbalance in their spine. Now in that situation when you are in a standing position you will have fairly decent aceh tabular anti version because the pelvis is retrofitted. But when you go in a sitting position again you will have increased anti version. Okay the sitting position increased anti version is okay but in a standing position then if you have increased and diversion I should hear the hip will impinge in extension as somebody stands and we'll leave it out. Anti really. So again I'm exaggerating the tabular component positioning just to demonstrate this concept. So in that case you want to reduce your asset tabular anti version and your cup will be more horizontal. But along with that your cup will also have only 5-15° of anti version and not 10- 25° or the higher spectrum of anti version. So to account for posterior impingement and to prevent anterior dislocation, what you're doing in that case is that you are artificially increasing your anterior coverage of the cup and reducing your posterior coverage so that you do not pop out the front and ideally in this flexible and unbalanced situation you should think about correcting the spine first so that you have a rigid balanced construct and then putting the acid Abdul um in a little bit more anti version. Now what if you have the worst problem possible which is a rigid and an unbalanced spine? Well this is what we call dealer's choice um You know typically you'll have to assess where the imbalance in the spine is and in most cases like I showed you in the Lambo pelvic mismatch, X ray. The there is a flat back so there is uh inadequate restoration of the lumbar Lord Asus. If that happens there tends to be a increase in posterior impingement and an anterior dislocation. So again I really in these cases you should really concern with your spine surgeon and move them from a rigid unbalanced category or classification to a rigid balanced classification. And then put the established component and increased version. But if they are reluctant or the patient is reluctant then what you may need to do initially is put the a cerebral component in less anti versions about 5-10° or 5-15° of anti version to prevent posterior impingement. Uh And then once the spine has been corrected re assess the patient and if they are presenting with instability of the hip you may have to do an acid tabular component revision or you may have to end up with a face changing or a lip liner to give it some more anti version. So I wanted to demonstrate a case. This was a case from fellowship in which we had a 53 year old woman who came with left hip pain and she had failed conservative management. She had some evidence of tomorrow as tabular impingement bilaterally and she had a prior arthroscopy with a liberal repair which is also fared uh injections had failed. She had these comorbidities but as you can see up north she also had lumbar decompression and fusion. So we ended up doing a posterior lateral hip for her. And uh we had pretty good leg length correction, pretty good restoration of the offset. The established component looked well placed But not enough anti version, one could argue. The night of surgery she dropped something from the bed and she tried picking it up. And since we had used extra in this patient which is like pose a little bit of a cane, she ended up dislocating and not even knowing until rounds. The next morning when we found her with this hyper flexed painful position because the expert had worn off. We then had to perform this closed reduction the same day for the patient and we got some cross table lateral x rays. And I'm going to draw out the acid tabular anti version in this. So you go from the anterior and posterior margins of the established component and then you draw a vertical line and you can see that we probably have about five or 10 degrees of ashtabula anti version. So not adequate in this case the hip was still stable. We placed the patient and an immobilizer and abduction pillow. She was made weight playing as tolerated and physical therapy was resumed as normal and she was discharged after a prolonged hospital stay. And there were no further episodes of instability. But what should we have done ideally in this case we should have gotten standing spine films too, especially assess where her spine IQ her spine balances because she did not have spinal pelvic fusion. She had lumbar fusion. But that means that maybe heard Lamar fluorosis was not adequately restored and all of a sudden she has this rigid, unbalanced spine or a flexible and balanced spine. Um and then we should have put the cup in a little bit more anti version as I showed you in a cross table lateral X ray. If she want to dislocate again, what would we have done? Well, number one, we could have consulted with us fine surgeons if her spinal balance was not adequately restored to correct that we would have revised the cup to more anti version. And once the cup is ingrown or used a multi whole cup, we could have considered a constraint. But then you are increasing the risk of impingement by reducing the jump distance in these patients. So that is not a good solution. Another option potential potentially is to consider dual mobility's whatever dual mobility dissociates, then it's no longer a closed reduction. You have to open the patient back up. So it's a complex interplay as I showed you previously. Now, here is another example of this patient. So this is the best ap pelvis x ray ap pelvis X ray for this patient. I could get in a standing position and you can see my template so this, you can argue that if this is an ideal ap pelvis. If you're looking at it, the patient is showing you more of an inlet when they're showing you more of an intellect. What is happening is that they have Lambo pelvic imbalance. Or they have sacral pelvic imbalance. They have more pelvic anti version. And as we know from our prior discussion if they have more pelvic anti version they tend to have native ASi tabular retro version. So the acid tabular version in relation to the pelvis is in a more retro vertical position. Now we you can see that there is lumber pathology in this patient. We counseled her. You know I had a multidisciplinary consult with the spine surgeons to see if she would like her spine corrected force. But given the lack of mobility with these severely arthritic inflammatory disease, uh inflammatory arthritis propose your hip. We elected to proceed with a total hip replacement. First from that case if I had increased pelvic anti version to begin with and I had a relative asI tabular retro version. What I have to do is I have to exaggerate my asset tabular anti version because if the patient is going to be held in this position and they go from a standing position like this to a sitting position like this. They will impinge anti really and they will leave her out posterior lee. So by increasing my ASI tabular anti version. One I'm providing a posterior buttress to prevent Um dislocation and two I'm reducing the risk of anterior impingement by allowing the hip to sit in a more favorable position. So these are the post operative x rays as you can see on the left where of course I had to restore the hip center of rotation by impact shin bone grafting from the femoral head to bring the hip out more laterally. But you can see that the anti version looks excessive and that's true as you can see on this three dimensional ct with the cross section. Um So here if you put this cup the cup is way pointing towards the ceiling and not pointing towards the floor. So it is way and we wanted to correct for this spinal pelvic imbalance in this patient. Now of course if she chooses to undergo the contra lateral hip we will do the same thing. Um And if she chooses to undergo spinal pelvic correction then we may have to think if she dislocates anti really. But hopefully by that point she has enough scar tissue to prevent that from happening. Now this is a unique case of spinal pelvic embassador. This was a 30 year old woman I saw approximately two or three years three years ago. At that point she was 30 years old. She came in with 10 years of left sided groin pain. She was otherwise pretty healthy but she had a surgery for developmental dysplasia of the hip at age 15 and this was done in South America and we weren't sure what the procedure was and it was difficult for the patient to explain it. But she had failure of non operative measures. She had severe limitations in the range of motion of her left hip. There was a significant limb length discrepancy and of course nostalgic and shortened, adopted gate. And these are the preoperative radiographs of the station. And again you can see that there is something going on which I couldn't really understand. Besides the uh you know there is of course a deformity in the proximal femur. There's a deformity in the left hand side pabulum but there is something going on the spinal pelvic junction. And I will describe that to you as we move along. But if you can imagine her left heavy pelvis is held in a very inlet type position. And her right heavy pelvis is rotated a little bit in a normal ap pelvis position. So she has this one sided inlet view and another sided almost a neutral view of the ap pelvis. So there's something going on and it is lopsided. Again you see this here you can you know you would look at the hip deformity and you're like yes you know of course that's a difficult deformity to correct and probably the procedure she was referring to was a shelf. Austrian Austrian army to correct her developmental dysplasia. But look at the sacral pelvic junction. You have a beautiful S. I. Joint on the right side but on the left side it is very hazy and in fact not even existent. So what did we do? We got a ct scan in ah that reveals the true picture on the left side. She has sacroiliac fusion. It's an auto fusion either developmental or something happened during the course of her treatment. And we just don't have previous x rays to see what's going on. But on the right side she does have a mobile sacroiliac joint to some degree. So this is something which is very challenging to address. In addition to her lumbar fluorosis. And this is a saddle view showing the same thing where her left sided pelvis is or heavy pelvis is fixed in this position. And that's what we have to work with. Once again the cities can showing that there is no S. I. Joint on that left side and you can see the deformity of the federal head which is uh you know fallen into this retro voted position in the proximal femur along with very less version given to the native asset pabulum. So what are some challenges to consider of course the patient age and the further dictation of a bearing surface. The limb length discrepancy and counseling the patient that you know to some degree. Her limb length discrepancy will persist because it also involves. And as I joined that is auto fuse, which we cannot correct and she probably she had a prior infection along with her surgery. So we have to think that even if the labs are notable and if you find that the frozen section shows high PMS per high powered field, we may have to consider putting in a space on the station. The an atomic challenges include uh, in addition to spinal pelvic imbalance six S. I. Joint, auto fusion, pelvic dysmorphia. So where do you put the cup in such a challenging case? Dysplasia. So we really want to keep that superior shelf. Otherwise our cup is going to escape superior early. And then federal retro version. So think about this. We just spoke about um pelvic anti version retro version as a tabular anti version retro version. But now there is federal anti version retro version that we need to consider. So how do you account for all these complex things? Well, you know, again for me, x rays are fine and I could have gotten long lengthened spine films. But I don't think that that was very helpful in this case. I really wanted to focus on the ct scan. So I created a three dimensional model with a three d printer of this construct. And this is the posterior view as you can see on the left side of image and the superior view as you can see in the right sided image here is the shelf is charming. The shelf that I want to preserve. And here is the native ephemeral head. So I want to, you know, kind of use this in my case to try and preserve whatever anatomy I have and correct whatever deformities I have to correct This is an interpretive view again from a poster or lateral approach where you see the GLP retractor on the right hand side that is towards the head of the patient. And my channel retractor is facing towards the foot of the patient. And you can see the shelf lost army. But look at the native aside tabular version. So her aside tabular version is in a lot of retro version. We already saw that her femur was in a lot of retro version. So if we put a hip in this position, she's of course going to leave her out the back. So in that situation we accepted that we would have to over and divert the cup and we would have to change the version of the proximal femur, which can be difficult to do. But here are the postoperative functional videos at two years. And of course she has a limb length discrepancy which was described to her. I said that look, we could give you a shoe left but she did not refer to use a shoe lift. So you can see this is her her uh military ability and this is the ability of her to sit in a squatting position and stand up with complete hip stability in two years. And let me show you the radiographs for this patient. As you can see. We've employed the use of the shelf. We've put in a 48 millimeter cups that gave us a 32 millimeter head. We use multiple screws because I was afraid of the cup. Living out at some point, we were able to restore the position of the hips center of rotation. We could not of course correct the leg length because of the S. I. Joint auto fusion, but we were able to change the federal anti version or the federal retro version by using an S wrong type stem to give it some more anti version even in the female. And then using Ronald's combined anti version technique, we made sure that her combined anti version happened to be around the 50° range between 30 to 50° and not on the lower end of the spectrum to give us the correction that we desire. And that has worked really well for her for two years. And we were very fortunate in publishing this with some of my colleagues. So you know, was what I presented very easy to understand. Unfortunately, I don't think so because I had to think like a spine surgeon remember my days and residency as a spine resident and then apply my total hip principles and and kind of think about the various different versions that we need to account for. But there are people in the uh the orthopedic community that think that uh this is still too simplistic that there is another layer that we need to unravel. And as we progress that's what we need to kind of do we need to unravel this as layers of an onion to see where things belong today. So this was an excellent review performed by Michael Mont about two years ago. So these are you know just, I wanted to summarize the findings in his review. So what is the impact of adult spinal deformity or a. S. D. On total hip outcomes? And he looked at this and and in the english literature there have been three studies published on this from 2000 to 2000 and 17. And the first two studies were an enclosing spondylitis patients with adult spinal deformity but also with hip pathology. And what happens in these cases is what they've said is that you know the enclosing spondylitis patients tend to have a lot of pelvic retro version because of pelvic retro version. They are fixed in this second type pelvis and they have excessive as tabular Auntie Ocean and that creates complications. So the popular if you do a total hip in these enclosing spondylitis patients and don't recognize this. They tend to have a lot of anterior dislocations and revisions for that also dislocate urz the people who dislocate have this higher degree of pelvic incidents to lumbar low doses mismatch. So more than 10 or 11 degrees and it's important to recognize that in cases of adult spinal deformity. Now what if you go ahead and correct that adult spinal deformity by performing astronomy's and fusions? What happens then on total him outcomes? So these are patients that have adult spinal deformity correction and then a total hip. I said that that is my preferred thinking that we should correct the spine first and then put the hip where it belongs in the pelvis. Especially as I showed you that the balance between the spine and the pelvis we can control to some degree but between the pelvis and the hips is very, very mobile and that's where the stress happens. So multiple studies in the 2014 to 2017 era have shown that by correcting the adult spinal deformity by fixing them in a you know less of uh pelvic retro version but more of a pelvic anti version position. You are reducing the tabular anti version and you're reducing the abduction. So again, as a stable anti version decreases the horizontal itty of your establishment increases. Um and by doing this um you know still by doing long segment Fusions. As shown by Bedard in 2016 you are still increasing the dislocation risk. And there was only one paper that through their their hat in the ring and said no you should you should still correct the spine first. What about previous spinal fusion on total hip outcome. So now it wasn't necessarily a fusion done for spinal deformity. It may have been a fusion done for a degenerative process or a herniated disc and some form of instability. Again in all these uh studies, what has been shown is that there is a higher risk of dislocation after you do a total hip in these final fusion patients. Because that lumbar sacral junction and the sacral pelvic junction is too stiff. So the hip is seeing a lot of this force. And if you increase the levels of fusion you have increased risk of dislocation. So what should we do should we do is find the spine deformity correction and a fusion in these patients Or should we just leave them in imbalance and perform a total hip. Sure. What is now emerging as we think about this more is that there are muscles that play an important role especially when you're talking about pelvic anti version and retro version. So in pelvic empty version. If you have and actually demonstrate this to you with a hip with a female level. If you have pelvic anti version like this and there is fixed in a patient. They tend to have a hip flexion contracture. They tend to hold their pelvis in an electric type view. They tend to have a flexion contracture and also an abduction contracture. And let me demonstrate that to you with this slide. So as the pelvic pelvis anti words, there is a hip flexion deformity. As the pelvis retro words um there is an extension deformity in this pelvis. So you can see that there is anti version happening. The Elvis is fixed like this. Now if in that case you do a spinal fusion and you fuse the spine like this your pelvis is also going to be fused in increased anti version and your cup is going to be retro averted. So then you would tend to exaggerate the anti version of the cup. But instead of that what if you did this? And this is the proposed algorithm. So you assess the patient if they have a hip osteoarthritis and an adult spinal deformity. Look and see if they have a hip flexion contract your present and you can do that very easily on the table. If they have a flexion contract your president. So you go on the left side of this algorithm. Then what you do is you go ahead and you correct you correct this hip flexion contracture by performing a total hit. So now instead of the pelvis being anti voted like this you are putting the pelvis in a more mobile area somewhere between retro abortion and anti version. So somewhere here and then you look at the spine. If after correcting the hip and correcting the pelvis. Your spine has compensated for it and gone from an imbalance to a balanced spine. Then you can just monitor just look at it. If it is still an unbalanced spine then you send them for a spine surgery consult and you do a deformity correction with the potential for revising the cup in the future. But let's say you do not have a hip flexion contracture present. And that patient says that you know I have these 5050 symptoms. But really I think that I have this ridiculous pain. Then what you want to do is you want to perform the spinal correction first, figure out where the spine balances and if the hip becomes symptomatic then do a total hip. And in that case I think of it as a rigid and balanced spines on a rigid and balanced spine. You are fixing it in relative pelvic anti version and your credibility is going to be retro voted. So in that case you go ahead and you put the cup in a higher degree of anti version. Now if they do not have a hip flexion contracture and they tell you that the hip is more symptomatic. In that case again perform a total hip. Put the cup in relative anti version and tell the patient that you are at increased risk of total complications. If that spine deformity progresses. So the new method of thinking is don't just willingly fuse the spine first and then do a total hip, assess the patient. You don't need any kind of complex long length films like the EOS films, look at their hip, look at the reflection contractor, correct the reflection contractor as you perform a total hip and then look at their spine and come back and address the spine. So with that I'd like to thank you very much for your attention. I know this is a complex topic, especially on a sunday evening but thank you very much. This is the johns Hopkins hospital as it stands today. And I welcome you to come and visit us and come work with us and hopefully we can learn from you as well. And this is my contact information. Thank you very much. Thank you Sammy A that was a splendid lecture once again. And uh it was really nice listening to you. It's of course it's a very very complex topic. It's only off last and 1 10. There's a lot of discussion on this until then it was just you treat the spine first, isn't it? Absolutely, absolutely right. And you know, we are extending this concept a little bit more because if you think if you have a loss of Lombard fluorosis, you have a flat back, you have pelvic retro version to compensate for that patients uh you know lean forward have positive spinal imbalance. Now, you know, we are only talking about the spinal pelvic junction and the pelvic hip junction. But look below that. Look at the me now you have a knee flexion contracture developing as well. So this extends further down the spectrum. You know the algorithm that you mentioned that you quoted with the Journal of Anthropology 2018 by seldom if you look at the four different options for the first three say that you look, you train the spine first and only in the absence of a hip flexion, contracture and with the symptomatic hit, you address the hip first, isn't it? Absolutely correct. Absolutely correct. Uh You know, I think what the principle that they are trying to highlight is that you know, there are certain things that you can you can correct obviously with your total hip but you really want to engage your spine surgery colleagues early because in a lot of these cases that spine the spinal pelvic imbalance can be more complex. Then just, you know, 34 levels of correction. And they may have to look at an entire picture of this patient and really council that patient that look, we can do this in a staged approach. But we may need to alter the surgical approach that we use for you use for you, especially the hip surgeon and B. We may need to perform revisions for you to prevent failure of these prosthesis. Yeah. The other thing that has come up is uh you showed an X ray of her petruchio with east pelvic and the ocean. Mm hmm. Right. And in that particular view we have it appears like a pelvic inlet view. And those are the patients who are at risk for as a tabular retro washing and partial dislocation. Alright, so in those cases and in those cases you try to keep the cup anti water slightly. The same thing applies vice versa. If you get an outlet view, you are having a risk of anterior dislocation and you're going to keep the cup slightly for studio. Am I right? Absolutely correct? Okay, I think so basically we can just have an idea by looking at the pelvic radiograph, isn't it? Absolutely. And as hip surgeons, I think that's what we are inclined to do because you know what as a hip search and if you talk to them about pelvic incidents, sacred slope and predicted they're not using, they are not very comfortable unless you're a sponsor. So I think it's very useful thing is that pelvic radiograph ap remember if it is and you wanted it looks like a inlet view risk of most interest location, you keep the cup and you want it right? Absolutely. And you know, even in those cases, what I would argue for is get a standing eight people this field always standing X rays, weight bearing X rays because sometimes when they lay down, things change completely for you and then you know, again your references has gone. But when you have to recognize this, if they're, you know, they're obviously laying down on your operating table and if you're doing an anterior approach, all of a sudden if that pelvis goes into more retro version and the tablet appears to be more antibody that can fool you. So you should recognize your standing X rays and template off of those and with respect to that particular X ray produce you where you have a pelvic inlet kind of you, what would you expect when you take a supine and uh sitting understanding was understanding of the setting extra that was a standing X ray and that particularly how what would be the supply, I mean how you know um and again in a part of this observation and I think that you know as we as we examine patients, I like to have them sitting, I'd like to see them standing to see where they are. I don't have x rays, I don't necessarily get those X rays. But if they have a a balanced spine to some degree you may have some change. So as you are going from here understanding you you may have some correction of that in a normal pelvis or a balanced uh flexible spine. But in her case given the amount of arthritis it was fixed in this position because as she was sitting she was lurched way up in the front like that. So I think that that was important to recognize in her that you know if she's sitting like this and I do a poster or lateral approach, she is going to go off the back okay. I think and I suppose in that particular case where we have our same salary increase pollution and erosion, increased risk of a suitable level promotion and posterior dislocation. Do you think if we approach it using an anti the hip surgery is going to have a benefit? Yes. So you know there is a lower risk of dislocation with an anterior based surgery. You're not you know affecting the posterior capsules. You're keeping that intact. But there are two you know suggestions that I have for that. Um One you have to be fast and you have to be comfortable doing an anterior hip. If you do it very less, you know then you risk in destabilizing the fema especially as you're doing the federal releases. So you have to be very comfortable doing that. Um two is that you have to really position that patient carefully and keep assessing the position the patient with the anterior approach. If I am doing an anterior approach, I tend to use a lot more express to keep confirming where the position of these components are because I do not have the ability to perform a complete range of motion analysis as I do with the poster or lateral approach. So in my hands I still feel more comfortable assessing limb length of set. Combined anti version anterior and posterior instability for a posterior lateral approach. So in my hands I would still do a poster or lateral approach for that patient as I should be. And do you think the navigation would help in improving the accuracy, reducing the risk of dislocation? Yes. So that is fantastic if you you know uh I was, you know, I learned a little bit of computers growing up and there's this term called giggle, which is garbage in garbage out. And the important thing with the hat is that if you use navigation, be very careful about your pelvic referencing. Maybe get a cT scan, maybe compare that maybe. And you know, you can take it to the next step forward. You can use a Meiko or some kind of robotic system if you have access to it to really understand your pelvis. But if you don't have access to these, um, then I think that the runaway combine anti version trick is essential. And if you learn that you will very rarely make a mistake in aligning your components. And do you have a computer based surgery at johns Hopkins for joint replacement for him? Yes. So we do have a navigation system and we're in the process of getting a robotic system. Okay, so Marco uh, Mayko. Yes. But also the smith and nephew has a robotic system called the Navio. Um, so they have a hip application and that's what we're looking at as well. And uh, the other thing was you showed the Coppola not as charlie remember are now combined and the Washington. It was really nicely explained. And is it the angle that the leg that's subhed ended with the horizontal. Is that the angle that you're talking about? Yes. So the, you know, as you know, as you, I'm gonna try and demonstrate this with this, you know, hit model. So if I am like this, my hip is reduced here. Okay. Um and if my tibia fibula were attached to the knee in a poster or lateral approach, what I would do is I would look at the angle that the tibia fibula make with the horizontal and hopefully the floor. And that will be the angle which gives you the co planer or combined anti version. And it should be within what I mean? What is the normal range? It should mean? So that's between 30° and 50°. So if you think, let's say you put your acid ambulance in about 15° of anti version and your femur in about 15° of anti version. 15 plus 15 is 30° of combined anti version. And let's say you go to the higher end of the spectrum, you say that I have someone with more pelvic imbalance. Uh and I want to put them at 25° of anti version in the asset pabulum and 25° of anti version of the female. As shown by the extreme case at the end, Then my combined anti version should be 50°. So that's why the range is between 30 and 50. So in that case you're once you met me uh to put their trials, your lectured, the media should be at 45° with the horizontal, correct? So this is the tibia fibula, my four. Uh this is the floor, that's the angle that I'm making that. Okay. Okay, so that's all the questions we have because it's a really tough topic. And I'm sure even I have to go through the lecture many times. A very, very important example that you quoted was the producer seo and that is one that I remembered so clearly that the concept of anti abortion and the risk of concept of paralytic and devotion, risk of s A tabular introduction and then you look for an increased and devotion for the couple. I think that's a very, very important case example that you show. Absolutely. And I think, you know, as a trainee surgeon, I was very confused when I would go into a case and my consultant or my attending would say, what is the version I'm like? Well, the version of what you know, the version of the pelvis, the acid pabulum or the female. Uh so you really have to tie these concepts together and understand that one affects the other affects the third. And I haven't even gone for the knee yet. But if we include the me that adds a layer of complexity to these cases and it requires a lot of planning and in some cases some experience to deal with these challenging patients. Okay, some years, thank you so much for joining with us. And we look forward for more lectures because it has been fantastic. Your perspective about joint replacement and the surgery in detail. I mean, it's going to be so enlightening for local audience, I'm sure, because you're sitting at Hopkins john Perkins here, the best center. I'm sure everyone is going to get the top class experience from your lecture. Thank you once again. And you look forward for more from your side. Thank you very much for inviting me. Thank you.
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