CME OnDemand: Bone Loss After Total Ankle Replacement-Foot and Ankle Focus: Dealing with Bone Loss after Total Ankle Replacement (TAR)

Foot and Ankle Focus: Dealing with Bone Loss after Total Ankle Replacement (TAR)

Video Transcription

On behalf of AOFAS, I want to welcome you to Dealing with Bone Loss and Total Ankle Replacement. Your moderator is Dr. Constantine Dimetricopoulos. Joining him are Drs.  Jensen Henry, David Pedowitz, William McGarvey, Karl Schweitzer, and Brian Weatherford.  You can find their full biographies and disclosures, as well as disclosures for program planners, in the program document posted in this course.  The 2024 webinars are provided free to AOFAS members and orthopedic residents, fellows, and medical students, with funding from the Orthopedic Foot and Ankle Foundation, supported  in part by a grant from Stryker. To support education programs like this, we encourage you to donate to the foundation on our website by texting GIVEAOFAS to 41444.  At this point, I will turn the program over to Dr. Dimetricopoulos to begin. Thank you. All right, well, Julie, thank you so much.  And thanks to the AOFAS for giving us this opportunity to present on this topic. And for those of you joining us, thank you for giving us some of your time for us to  present this topic. So this evening, we're talking about ankle replacement and bone loss, how it affects  our decision making in primary ankle replacements, and also in revision ankle replacements.  You'll also hear a talk on the incidence of revision ankle replacement and what the literature has to say about outcomes thus far. Please ask questions during the talks.  I will keep an eye on the Q&A, and for short questions, I'll ask the faculty at the end of their talk, but for maybe longer questions, we'll deal with those at the end.  We have about an hour's worth of lectures with 30 minutes of case discussion. So hopefully this will be interactive and a little bit of fun for us and for you.  I'll go ahead and introduce our first speaker. So Carl Schweitzer is an assistant professor of orthopedic surgery at Duke University.  He's actively involved in training the fellows at Duke and has a special interest in ankle replacement and also revision ankle replacement.  Carl is going to talk to us today about bone loss as it pertains to the tibia and primary ankle replacements. Thank you.  Thanks, Konstantin, and thanks to the other presenters and all the attendees. I've been looking forward to doing this.  So I was tasked with tibial bone loss and primary total ankle replacement. These are my disclosures relevant to this talk.  I am a paid Stryker consultant and speaker related to total ankle, and I do show one case related to a custom implant with Restore3D.  So the overarching themes here are the high points. Don't let this distal tibial bone loss problem move you away from doing total ankle arthroplasty  for your patients to give them their best outcome. The technology, the techniques, the implants, they're all here to help with it, to ensure a successful outcome for your patient.  These can be certainly challenging cases, but I would argue that these can be even more difficult fusions if considering that.  I'm not trying to steer anyone away from arthrodesis, it's still a good option, but there certainly are healing challenges.  As you'll see in the setting of compromised bone, stress-shielded bone, eroded bone, missing bone, osteopenic and parotic bone, and dead bone.  So as foot and ankle surgeons, we often dig ourselves into this tunnel vision, but there's other arthroplasty surgeons out there, and I think we should pay attention to what they've  done and what they're doing as well, and I'll highlight a little bit of that tonight. So you could imagine that perhaps our total knee partners are years ahead of us when we're  thinking about bone loss and how to deal with that with primary and revision total ankle. They've been doing these techniques longer, they've developed them, they've written them  up, they have larger databases, they have perhaps better implants. But I think it's important to look, you know, they do have classification guides that dictate  treatment that lead to outcome, but certainly they have things that look somewhat familiar to us, you know, it could be, especially in relation to total knee arthroplasty, cones,  sleeves, asymmetric varieties of these to deal with bone. They have augments on the femoral and the tibial side, they have asymmetric rods and  stems, they have rebar techniques involving screws and cement, and this has been in their literature for some time now.  So our, in fact, our total knee partners years ahead of us, I think at least one thing I learned in residency that an ankle is really just an upside down knee, you know, so we're  not, perhaps we're not too far off. I think we still have a ways to go, but I think we're on the right track as you'll see in all the talks.  So when tasked with this talk, you know, I questioned, is this really a thing in primary total ankle replacement, distal tibial bone loss?  And certainly the answer is yes, and we definitely need to pay closer attention to restoring this in terms of joint line.  There's multiple ankle arthritic joint line studies showing there's a tendency preoperatively and even postoperatively for still having a persistingly elevated joint line.  But it's not all just the physical bone loss. There's also poor metaphyseal bone quality that we deal with.  Dr. Henry and Demetriopoulos in their institution showed that perhaps stems and keels provide  better tibial component longevity compared to lower minimal resection implants with pegs.  I think as we'll point out, you know, modularity in total ankle system, whatever you're using is certainly critical and you need to have flexibility in a lot of things in relation  to the tibial component, the thickness, stem or keel heights and options related to that, stem diameters and coating.  So in this case, I would argue that more metal is better and less poly is likely better in relationship to concerns about longstanding osteolysis, perhaps overstuffing the joint  and joint kinematics as we'll point out. So what are the etiologies of bone loss in relationship to the tibia and primary ankle replacement?  Certainly it depends on the arthritic component. Is it post-traumatic and you're dealing with cysts and erosions, perhaps fracture non-unions?  Maybe this was an open fracture history and there's bone loss. Maybe you're dealing with a psoriatic or rheumatoid patient with cysts and relative osteopenia  on all the relevant medications that affect their bone health. Maybe you're dealing with a crystalline arthropathy.  Less commonly though, there are things like tumors or tumor-like lesions. Probably the most common one that we deal with is avascular necrosis, but also cysts,  whether they're aneurysmal bone stiffs, unicameral or NOFs. As we mentioned, osteoporosis and osteopenia certainly play a role here. Part of the removal is critical.  It leaves voids and oftentimes leaves awkward areas of bone between prior screw removal, and so we have to deal with that.  We have to perhaps deal with ankle non-unions and malunions or sequela of infection, whether it's septic arthritis or osteomyelitis, and in some settings, we have to perhaps deal  with stress shielding and voids related to harder removal from prior ankle fusion takedowns, whether for nonunion or malunion.  So the principles here are really to restore the joint line, and perhaps, and I was told not to talk a lot about the literature, but I think it's important to mention that we're  probably not as good at doing this as we think we are. We know that the joint line is certainly elevated preoperatively in ankle arthritis patients.  That's been demonstrated in several studies. It's also been demonstrated that we really just, after we resect the bone, we just put it back where it was. That's our tendency.  That's what the literature shows. We don't actually perhaps restore it to their normal contralateral side, and when we don't  do that, it leads to more impingement, reduced ankle dorsiflexion. It actually doesn't seem to affect the plantar flexion, but it obviously does affect the  total range of motion and has been shown to reduce outcomes in terms of PROs at one year. It's important to get metal on good quality bone.  I think we all appreciate that in any joint that you're performing an arthroplasty on. I would recommend augmenting with metal.  I think there can be some issues with bulk allografts in terms of stress shielding, resorption,  or even late fractures and collapse, and I think in general, as our knee surgeons have showed us, metal makes a better metaphyseal void filler.  You also have to think about implant stability, not just joint stability, but implant, and  so things that's been shown, you'll probably see tonight, things like stems and keels generally lead to better tibial component survivorship in order to bypass compromised bone.  Obviously, the standard principles apply. Joint stability is critical in terms of ligamentous stability and alignment, along with rotation.  In terms of when you're talking about primary revision, when you're dealing with bone loss,  research for medullary referencing has been shown to provide better accuracy, particularly  in the sagittal plane, and I think there is a role here for patient-specific instrumentation, the PSI technology.  I think that can really be a good supporting tool as you plan for these cases. So it's too late on Eastern Standard Time to dig through lines, but I think it's important  to recognize what's out there. Certainly, the obvious thing would be just to check the contralateral side, but this  HSS study outlined a joint height ratio in order to determine where you're at in terms of an elevated or depressed joint line.  As I indicated, actually, preoperatively and postoperatively, total ankle replacement patients have an elevated joint line compared to the normal contralateral side.  In postoperatively, there's really no significant difference, so we haven't really lowered the joint line if it was elevated on average.  So I think that's important to note that we're perhaps not, maybe we're not doing as good of a job as we think we might be. There's also other ways to measure this as well.  I don't want to deliberate too much, but instead of ratios, you can look also at absolute values, and I think this paper out of Baltimore is also worth looking at as well.  So my focus was to get to the cases, and so in digging through the 350 or 400 total ankles I've done so far in practice, actually found more examples than I thought I would, and  this one may, you may wonder why we're including it in this talk, but this is a 57-year-old female who's had rheumatoid arthritis for some time.  She's on two medications for that, and she has vitamin D deficiency, history of bilateral ankle arthritis.  She's had a prior total ankle replacement with one of my partners and came to me for her other side, and you can see she has cysts, and you could argue that perhaps these would  get resected even with a minimal resection implant, but she has other concerning features  inflammatory arthropathy, concerning bone health, and so for this, I relied on a patient-specific  CT-guided approach to kind of plan out the resection and what I might need to get back to the better bone.  Of course, you know, supplemented her vitamin D and then went ahead with an intramedullary-based total ankle replacement.  Didn't have to do any type of augmentation on the tibial side or the tailor side, but found it important, and I included pretty much all my cases of prophylactic fixation  of the medial mellitus. That area of bone can get thin, and I would say anecdotally, since I put that screw in,  I've seen certainly less fracture, less pain at that 6- to 12-week mark when they increase their activity out of the boot.  So this is a relatively straightforward case, but I think it's important to recognize that  bone loss, however you consider it, is more common than you might suspect in your practice,  and this is a one-year post-op, and you can start to see that something might have happened,  and she did have some increased pain, I believe around three months, and if you go back, you  know, I think it's important to recognize we wanted to talk about complications of things that we're doing.  You know, this is not a benign procedure, reaming the tibia, and perhaps I got a little too anterior and created a stress riser, and this patient had a fracture around three months  postoperatively, was able to treat it conservatively, and it healed. It did affect probably more the sagittal plane alignment, but ended up being stable  and healed, and she moved on from it. So I think important to highlight some of our own complications when we're doing what I would consider relatively straightforward cases.  This is a 54-year-old male who's generally healthy, active, had an ankle fracture and fixed in 1999, and obviously, this is more of the case, you know, you're thinking about  in primary total ankle where there's bone loss in the distal tibia, large voids and cysts, and so for this case, you know, it's important, again, to get back to better bone,  and so that resection's a little higher, and so I have to build the joint back down, and  so I use an augmented tibial component, intramedullary base, and I do an impaction bone grafting  technique before I put the stems in in order to fill in some of that bone to provide better  support and healing, and for me, that's generally a mixture of auto and allograft, and as I highlighted, important to fixate the medial malleolus to prevent it from fracturing, and  the pathology on that ended up just being a benign cyst, so nothing concerning there.  This is another example here, a 46-year-old male who's a welder, and he had a pretty significant trauma to some of his proximal bones, his femur, his upper extremities, but also had  a lot of ankle and hindfoot trauma, I believe a calcaneus fracture, and ended up having a fusion, but also had a chronic issue with his distal tibia, perhaps an old impaction  injury, and this bone doesn't look particularly healthy, certainly nothing that I would consider  putting a metal component on, no history of infection, and I think that's important to point out when you haven't taken care of the patient all the way along to always at least  ask about wound healing issues, I check labs on all these patients, and this patient was really offered a TTC or an amputation, and neither of those options were appealing to  them, and so this patient's now five years out and chose to get back to better bone by resecting more of the distal tibia and then building it back down, similar technique with  some impaction bone grafting on the distal tibia in the canal that we've reamed, and that is, this patient's done very well, and he still has his ankle and has no pain.  This is a younger guy, a PhD, prior issues with alcohol in his head, a lot of issues systemically with AVN, has had both hips replaced, both shoulders replaced in his head, this  ankle actually has bilateral problems, but this was the primary issue here, and obviously  there's a compromise of a significant portion of the talus, and I don't want to steal Weatherford's thunder here, but we'll focus mostly on the tibia.  That's fairly compromised bone, and I would argue that this also isn't an easy ankle arthrodesis.  I actually think trying to do a total ankle on this patient is perhaps more reasonable and perhaps has better healing potential and less fraught for complication, and so for  this patient, you can see his other side, he had a harvested free vascularized fibulograph  for his hip that eventually went on to a total hip, but for him, ended up having to do what  I would call a combined total ankle or a tater, as we call it in the research triangle here, and essentially bypassed the bad metaphyseal avascular bone, and for this, I do like to  use patient-specific instrumentation. It helps me determine my best coverage on my tibial component, so then I know what I'm doing down below.  It just makes it a more predictable procedure, so even in this case, where you might consider  a TTC or something like that, this guy's four years out, and yeah, these AVN patients are not pain-free. We set that expectation. This is a different systemic process.  They have more chronic pain, but he is dramatically better and can move his ankle.  He's happy with that. The vast majority that I find relevant to this talk in terms of cases is really post-traumatic,  and a lot of it involves hardware, so you have all these prior screws in this older guy with post-traumatic arthritis that had this fixed years ago and has these avascular  segments in his distal tibia, and this can start to steer you away from a total ankle, but I think with the technology that we have today, it really is doable, and I truly believe  it's probably the best option for this guy compared to an arthrodesis. This is a very difficult fusion to get to heal with standard techniques, and so for  this, I don't do all of them with PSI, but a lot of the ones I showed have it, and so I was able to do essentially a standard total ankle and get past that bad distal tibial  dead bone, and as I showed here, I do the hardware removal first. I'll point out in other cases. I think that's really important to stage these.  As simple as it seems to take out some screws, but many of these have been in for 10 to 20  years, finding the right screwdriver, et cetera, I think as a technique point, it's important to stage these.  I've had some issues with patients healing incisions made for hardware removal, and I certainly was happy that I had staged it and not committed them to the whole procedure  all at once, but doing CT guidance allows you to plan out where your bad bone is, what kind of implant system or primary or revision that you might need in this primary total  ankle setting, and I think it's a helpful tool in my practice. Here's another example of a 51-year-old guy that had a trimal ankle fracture, distantly  ended up having some hardware removal and a scope, no history of infection in his labs or normal, but again, really bad distal tibial bone, and I'm using CT guidance here to plan  out what I'm going to need to get back to better bone and how I'm going to bypass that defect and provide a stable implant that'll provide a good ankle replacement that's pain-free  for the patient. This has really been a helpful tool for me in my practice. This is that patient at five years. Again, similar techniques to what we've described.  You can start to see repetitive themes here, but this works very well, and there's still revision options and things like that if this is to not work out, but I think this is a  much easier replacement than it is a fusion, and this is a 60-year-old male cabinetmaker, healthy, well-controlled diabetes who had an ankle fracture and fixed over 25 years  ago and then eventually had it fused, came back with subtalar pain, so this is a takedown consideration.  They generally do a fluoro-guided diagnostic injection to make sure they get subtalar joint relief. He was in a little bit of varus.  I know it's hard to see here, but I think you'll see when we go to further slides when you see the resection gap, but again, staging the hardware removal, I think that's important,  and there's a lot of stress shielding. This has been a fusion that's been in place for several years, almost a decade, I believe,  and so this bone is compromised, and I consider this distal tibial bone loss.  This is kind of a qualitative thing, but I wouldn't choose to do a minimal resection implant here on metaphyseal bone that's fairly soft and probably not going to be supportive  long-term for the patient, and so with pre-op CT guidance, you can kind of plan out where the joint line was so that you can kind of try to restore the anatomy as best as possible.  It also allows you to see all the voids that you created when you took out all the hardware,  and again, allows you for better implant selection, sizing, and just overall planning, makes the case go a lot smoother.  So the hardware was taken out, and then stage two, this is obviously a decoupled cut. You can see there was a lot of varus built into this fusion, and that will correct with  the resections. I don't want to spend too much time talking about takedowns, but it's important to get  a good gutter resection and get the joint moving, provide prophylactic fixation of the malleoli. I generally do both malleoli on this one.  I didn't do the fibula, but I think it's an important point. You can also put a screw up the distal fibula because that's been stress shielded as well,  and this is, for me, this is a primary total ankle. You know, I generally consider this implant, although it can be controversial, I consider  this a primary implant, although it can be also used in the revision setting, and this is the patient at six years post-op.  He has no hindfoot pain, so restoring motion and mobility to his ankle actually relieved his ankle pain.  That can sometimes be a leap of faith for us, but it can work in certain settings. I think the diagnostic injection is important to that.  Being critical, I don't have full-length views here, but I probably put the tibia in a little  bit of varus here, and I ended up with, despite trying to kind of minimize my resections, did end up with a 15 millimeter poly.  So in hindsight, may have tried to put more metal in and thicken the tibial tray. This was probably earlier in my career, and like I said, maybe I should have augmented  the tibial component to provide less poly thickness. So in summary, you got to recognize distal tibial bone loss in the primary total ankle  setting, and I think there's a lot of good comparisons between the total ankle literature and what we're trying to do here. Keep in mind that it comes in different forms.  It's not just what you see on the x-ray. It's not just tibial height loss, but it can be poor quality bone. There's many examples that we went over tonight to show that.  For that, I rely more on stems, but keels are also reasonable, and I think both are certainly better options than pegs in terms of tibial fixation.  And I think having some degree of modularity in whatever system you're using is really important in giving you flexibility to get the patient the best component stability.  I think CT guidance can be helpful in these cases and can be a good tool. I generally recommend staging the hardware removal and protecting the malleoli,  particularly on the medial side.  I do think impaction bone grafting as they do in total knee arthroplasty is an important point and can be helpful to provide additional support and healing once that incorporates.  I think there's still a lot to be learned on this topic. Certainly this has expanded our total ankle indications, having these systems available that allow us  to remove the bad bone and replace it with metal. And I certainly think these are much harder ankle fusions. Certainly as we go on, I think we're gonna learn more  about on-growth versus in-growth or porous coating versus porous metal and how we might incorporate some of these other techniques that they have in total knee arthroplasty.  Things like cones and sleeves and asymmetric augments and maybe more relevant for the tailor side.  But I think we can also learn a lot in terms of other techniques that they use in terms of impaction bone grafting, cement and rebar techniques.  These are my references and thanks for listening.  All right, Carl, thanks so much. Our next speaker is Brian Weatherford. Brian's from the Illinois Bone and Joint Institute.  Brian has for some reason thought to do two fellowships, not clear why, but did a trauma fellowship and then a foot and ankle fellowship. He's practicing now outside of Chicago  and Brian's gonna speak to us about bone loss on the talus and primary ankle replacement.  Yeah, thank you for having me. Here's mine coming up here.  You know, if you guys can see everything. All right, is this showing up okay, guys? Can you see it yet?  Looks good. Yeah, we got it. All right, good. Yeah, I was actually going for honorary Canadian citizenship with the two fellowships,  but yeah, I don't know what I was thinking. So these are my disclosures. So of relevance to this talk, I am a consultant for Stryker  and some of those implants are used in these cases.  Carl's talk was much smarter than mine. So this is just gonna be about showing some cases and what I did well and what I probably didn't do well.  This is my basic decision tree for tailor bone loss, which is something that is, I would say definitely more of a guideline than a rule,  but these are the things that helped to inform me really to decide whether I can do this in one stage versus two stage. And number one is obvious. Do I have enough to work with?  Do I have enough bone available? The next question I think is a little bit more subjective, which is, do I think that bone is going to be able to support an implant?  Not only is it there, but is it quality bone that will withstand loading? And then the third question, which usually goes along with most ankle replacements  is can I manage my tailor bone loss and simultaneously correct any underlying deformity? And I think all of those things kind of go into your planning.  So you guys see here on the image, right? So we've got some avascular changes, cystic changes, arthritic changes of that ankle.  And then if you throw in this deformity of the hind foot at the same time, I think for me, the answer is pretty clear, right? So if you're looking at any of these questions,  you're asking yourself these questions as you go along and the answer is no to any of these things. And I would recommend strongly considering a two stage ankle replacement,  which is totally okay to do as long as you and the patient are on the same page with what you're looking for.  So my general tips for this, again, which are somewhat vague because these are all kind of individual cases. Don't be afraid to freehand your cuts on the talus.  I do use a lot of patient specific instrumentation, but I find on the talus that no matter what, I end up really fine tuning freehand.  And I would say I'm interested to talk to Carl about this because I find that I do use some bone grafting on the talus, but I find that cement is my friend a lot of the time.  And so I'm using cement for defects or for increasing my fixation on the tibia and talus side.  I would say when doing these cases with tailor bone loss in a primary setting, I would consider a quote unquote revision implant. You need to spread out your loading  along the entire surface of the talus or as much as you possibly can when you're already missing bone. And so I would say that in those situations, there are implants available  that can help to kind of mitigate that. And then last thing is when I'm doing these cases, I always plan for a two-stage and the patient has to be on board with that as well.  So when going into these cases, I have a pretty clear idea of what I wanna do, but if there's any question, you have to have everything available  and know that you need to bail basically to a two-stage procedure if needed.  So my single stage example here.  So this is a guy who has a history of a previous talus fracture. So he had a history of wound healing complications, but the fracture was remote, it was more than 20 years ago.  No issues since then, got preoperative labs, even aspirated his ankle or did the best I could to aspirate that ankle under fluoro.  But this is his situation with his bone loss there.  He has minimal associated deformity. And like I said, I mean, this guy, I talked to these patients beforehand to say, listen, we are gonna go in there and this is our plan A,  but plan B is this, and you need to be prepared that there is a second surgery. And if you're not prepared to do that, then we need to discuss whether fusion  is the best situation in these circumstances. Interestingly, and I don't know if you guys have ever seen this, he claims that he did not have a subtalar fusion.  So that either he is not being honest with me or that guy's subtalar joint actually auto-fused in this situation, which was beneficial.  So not a lot of floor images, but this is the revision implant here.  In this situation, I think this is really important. I think we have limited bone to rest this implant on. I think if you're careful with your cuts,  as you can see, you come right across the top of that talonovicular joint with your cuts there. I do think that patient-specific instrumentation can help you to plan that cut.  But I think this is an implant that can help you to withstand those forces as well. And even in these situations with this limited bone available,  starting these patients weight-bearing it two to three weeks post-operatively.  So the next issue, which I know Carl touched on already, but I'll just kind of re-emphasize it. So it's not just bone defect, but bone quality, right?  So this is a woman who's in her early 50s with a history of rheumatoid arthritis. She's been on chronic steroids and you can see the avascular changes of her talus there.  And I think for me, this is an unsolved mystery. I don't do a lot of total talus cases. I'm still not sure kind of where that's gonna go, although I readily acknowledge  I don't know what the answer is.  So this is what you're dealing with here. So this is CT again, showing sclerotic bone, basically subchondral fractures involving a lot of the talar body.  So in this situation, I chose to start by fusing the subtalar joint. And again, I'm interested in opinions on this because I don't know, or I don't really believe  that this necessarily revascularizes the talus, but I am looking to create at least some healing to create a foundation for an implant.  And so she went on to have basically partial healing of that subtalar fusion, but enough where I could do this, where I could now place an implant.  And again, you'll notice I also at the second stage fused her talonavicular joint just to get additional support for that implant.  And so she's now just over the one year mark at this point and seems to be doing pretty well. But I think the counterpoint to this is that it took two surgeries for me to get there  when possibly one would have been just as effective.  All right, so the last case was actually for me, I would say, I'm definitely open to some critiques and interested in opinions on this. So this is another patient.  You can see is a lot of associated deformity here, hindfoot valgus, peritalar subluxation, avascular changes of the talus. And his preoperative CT scan  is gonna show you some of the same. So you've got cystic changes, avascular changes and associated deformity. So for this, this is for me automatically,  if you're considering a replacement, this person is getting their deformity corrected and then getting an ankle replacement after that's been addressed.  So this is where, for me, again, I'm showing this case, even though I'm not loving the results. So we did a triple arthrodesis, do a lateral column lengthening.  I was very happy with the correction we got in this case. So happy, in fact, I don't know what I was doing that day, but I was like, yeah, you know what? Let's write it out.  Let's see how this goes. This ankle looks great intraoperatively, even had some stress images. And I should have trusted my initial plan,  which we had planned for a two-stage all along. This patient had other factors going on. He actually has a contralateral amputation from a previous traumatic injury a long time ago.  So it was very challenging for him in his recovery process from this. But I should have, in hindsight, stuck with my plan because even though this looked great early on,  you can see he's got that anterior ankle arthritis still, but I was very happy with that correction. The ankle joint overall is looking pretty good. Not surprisingly, at one year,  he collapsed through that avascular area of the talus. His arthritis progressed and his hind foot valgus or valgus through the ankle progressed.  And then doing the case itself, I think, first of all, I think my cut on the talus is probably off to begin with. But you can see that talus implant is resting pretty medial  on that residual bone there. I ended up having to shift his heel to kind of chase that. And for me, again, part of this is probably intraoperative technique,  but I think if I had just stuck with my plan initially and gone right to that two-stage, which I knew he was sufficiently healed from that initial correction,  maybe some of this could have been avoided. So here he is at one year post-operative. And so as Carl pointed out, he's got a thick polyethylene, a tall polyethylene in there  trying to make up for joint laxity and or to restore his joint line. He still got some residual valgus. And so I think maybe the story isn't fully done with this guy,  although he's doing reasonably well at this point in time.  So, yeah, I mean, I actually found this to be a little bit more challenging topic because I know there's certainly not a lot of data on primary arthroplasty with tailored bone loss,  at least that I could find.  But for me, the technical aspects that I look at are can I do it in one surgery? And the things that I'm looking at are how much bone do I have available?  What's the quality of the remaining bone? And what's the associated deformity? You know, my tips that I would say are that, you know, I think free handing these  is something you have to get used to if you're gonna do this. And I'm not just saying just blow through the cut and do whatever you want. I'm saying, even if you're using  either external alignment guide or patient-specific instrumentation, that you have to get comfortable with the fact that you may have to revise that cut  to get the balancing that you need. For me, cement, I do think is useful in these cases,  although again, I'm interested in other opinions. I also use a lot of fluoroscopy, which, you know, sometimes can be challenging and the fluoroscopy techs certainly challenge me,  but I do think that it's helpful in these cases. I think using a more robust implant when you've got tailored bone that's missing or insufficient is important to consider.  And lastly, it's okay if it takes you two operations to get there. So, you know, it's not a defeat or doing the wrong thing for the patient,  as long as you and the patient are on board with what needs to be done if they wanna pursue an ankle replacement in the setting of tailored bone loss.  So, thank you.  Thank you, Brian. That was a great talk.  I wanted to kind of follow up. We have a little bit of time for your session, but, you know, I think you showed a great example of using subtalar arthrodesis  to really build up the talus, particularly when there is some tailored body remaining. So you have, you showed cases of avascular necrosis with collapse of the dome,  but you still have some viable talus in the body. And, you know, I think that's a great use of the technique. Yes, it's a two-stage operation,  but you're able to really save bone, right? You're utilizing the talus that is remaining and able to put a straightforward standard implant  in your replacement. So I think that's a great technique.  I think I share your philosophy of, I tell patients sometimes it's gonna be in two stages and sometimes it's gonna be in one, and we always do our best.  It doesn't always turn out the way they want it. Everybody wants a one-stage operation.  One thing I saw in your case is, you know, you're using cement in the tibia,  and I see cement all through the stem. Now, I've used it on the base plate sometimes, so I'll impact my stem, and then I'll use some cement at the base plate,  so I'll get some initial fixation. And then I'm hoping that there'll be some bone healing onto the stem. Have you tried that technique? Have you always cemented the entire stem?  And how do you get the cement in? I've heard of different techniques, but what is your technique for getting the stem and the tibia cemented? Yeah, so I didn't always cement it.  I was heavily influenced under duress by someone that I used to work with, Steve Haddad,  about using cement. What I would say, so one of the things that I found it useful in is that, you know, I actually agree with all of Carl's points  about getting implants in metal on good bone.  One of the ways that I found the cementing technique  useful is it gives me more freedom to manipulate that implant in the metaphyseal bone. So in some of these cases, I'm actually over reaming and steering my implant,  and then using the cement to help fix it in there.  The actual technique itself is not that elegant. So I'm using an osteotome, usually a curved three quarter or one inch osteotome, and then a Tumi syringe,  and using the osteotome like a backstop, and then we'll fill up, you know, a decent amount of cement on that, press fit it up into my, basically press it up into the tibia,  and then use my thumb as the pressurizer  to put it up there.  You just have to make sure the hip surges aren't anywhere close to the OR when you're doing that. I understand. The judgment is gonna be, yeah.  It's horrific, yeah, I know, it's all right. But again, I'm interested in alternative techniques. I have always been trying to get these patients weight-bearing sooner,  and so I thought this was something that was gonna help me in that, but I wonder if it's just something that is kind of my security blanket.  And then I'll ask this question. Now, this was a great question from the audience. You and Carl both showed various stem lengths, right? And so how do you decide,  maybe Carl go first, then Brian. How do you decide how many stems,  maybe how many pieces, how many press fit segments? Brian just talked about over reaming, which is, I usually, I really try to avoid that, but that's an interesting idea,  something to really consider. But Carl, how do you decide on number of stems? Give me a 30-second answer. How do you decide on number of stems and how many you're gonna press fit?  So for me, it's always a minimum of three. I'll have a pre-op idea based on my CT scan and perhaps some pre-op CT guidance, patient-specific technique.  But in drop, as you're assembling it, you're getting a feel for stability and I wanna bypass the defect and get into better bone. And then once I get to the point  where I feel like the stem is nicely stable,  then I stop.  The one thing, just to answer one of Brian's questions, I do use a lot more cement on the tailor side than the tibial side.  I don't think there's anything wrong with using it on the tibia.  And certainly the way he describes it makes a lot of sense, but just wanted to add that.  So, I think that's what's interesting about this. So I just do three stems  and I haven't gone past that in years.  So, and again, that's where that cement technique comes into play. Now, I'd be interested to see if that becomes an issue down the road, because I've only been doing that  for about three years now.  And so, yeah, I mean, I think this is just one of the many unknowns about ankle replacement is that I agree that as a trauma person, I wouldn't put a femoral nail in  that didn't have a good diaphysial fit, but somehow I feel comfortable doing it with an ankle replacement.  But yeah, I mean, anecdotally, I guess, and I'm interested to look at this, I've been, even with early weight bearing of these patients with three stems  and metaphyseal bone and older patients with cementing, their knock on wood so far doesn't seem to be a huge incidence of loosening of the tibia or stress shielding  or associated fractures or any of those things. Well, there's a great question in the chat about when, if this gets infected or it fails, you're going to have a challenge  getting all that cement out. Obviously you would have to get it out just like we get out cement with any other arthroplasty.  I think it's for that reason that I've kept my cement at the base plate and avoided cementing the stem and have had good results, but I think we need to look at these  and study these in the future. So we'll move on to the next topic. We will have obviously much more opportunity to answer more questions. And as you guys think of questions,  please put them in the chat. Our next speaker is Jensen Henry. Jensen's an assistant professor of orthopedic surgery at Hospital for Special Surgeries  is one of my colleagues and partners.  She's also education director for foot and ankle service at HSS and very interested in ankle arthritis and ankle replacement. So Jensen's going to talk to us  about revision ankle replacements. We just showed you some challenging cases. They don't all work.  Failures are coming. Even in the best of cases, our ankles will need to be replaced. So what should we be thinking about in terms of revisions  and what does the literature say about outcomes?  Fantastic. Thank you, everyone. Hi to all. If you have any questions, obviously reach out and then please let me know, of course, if there's any audio or video issues.  So we're going to go over ideally epidemiology and outcomes and knowing that some of the limitations that we've already discussed. And so we know really  that revision total ankles are coming. We also know that the volume of total ankles performed annually is increasing. And so you can see these graphs  which always lag behind several years from where we are because they're all based on healthcare databases. But we can assume that if that number increases every year,  there's probably going to be some type of measure increase in the number of ankles that require revision. And this has actually been studied. This is a nice study from Irvin Oh  from a few years ago, where they looked at the burden of both revision as well as primary total ankle. And they found that from a 10 year period from 2010 to 2020,  our total ankle utilization in primaries increased by 284%. And whenever you compare that to what's going on in the hip and knee literature,  it's just increasing at a much greater rate. In the same period, total ankle revisions rose by 28%. So certainly we're not seeing that same volume  but we still are seeing an increase. And the amount of cases in which we're explaining total ankles and converting to a fusion is decreasing. So we're seeing this higher likelihood  of revisions across the United States. And this is another little graph from their paper. And you can see that the first graph on the top is showing how total ankles  in the primary setting are increasing. But then when you go back down to the revision settings, that's the dark gray bar here, X plan is black.  You can see that our revisions are growing as well. And so if you do this math, even if our techniques and our survivorship for primary total ankle are getting better,  and we know that there are about 10,000 total ankles that are going in the U.S. annually based on estimates. And so if you assume a 5% revision rate in the early period,  which is what a lot of current studies are showing, each year that we're doing primary total ankles is gonna generate something like 500 more revisions in the first few years alone.  And so that's something that we are gonna need to prepare for. And it's also important to remember, and I think Carl spoke about this as well,  our indications are expanding for total ankles. We have younger patients, we have more complex patients, patients with existing hindfoot fusions, patients with bone loss,  patients with multiple prior surgeries. And so we are gonna see these, and we're gonna see these in complex patients and younger patients. And although this hasn't been studied,  I anecdotally find that patient expectations really seem to be changing. The baseline assumption is not that they'll just convert to a fusion if or when their total ankle fails.  I think there will be an increased need for patients who want a revision total ankle. And so when we talk about revision total ankles,  you know, if you're a big Lord of the Rings fan, you can say that they're coming, but I'm obviously young on the panel here, but I'll even say early in practice,  I'll say that, you know, if I'm gonna quote the Poltergeist, I think that they're here, and we're really starting to see them in some of the difficulties with them.  And so when we look at this from how do they actually do, I'm gonna break it up into three segments of time. And so we're gonna go to the quote unquote historical context,  but it's really quite recent because there's not a lot of historic data on these. And by historic, I mean, pre 2018, 2020. And a lot of that really was limited by our implants.  A lot of these patients ended up being converted to fusions. So I'll throw a couple of JBJS studies from 2013 out here. And these are really some of the biggest early studies  on revision total ankle. The first is from Hinderman's group where they looked at 117 total ankles that were all revised with a Hintagra mobile bearing  plus or minus a custom implant for bone loss. And they found that 15% of those revisions  ultimately failed and went on to additional surgery. And I highlighted here, and it's something that we're gonna talk a lot about over the next 10 minutes.  What are these causes of revision? Number one for them was Taylor loosening. And of the patients who survived, about 77% of them were very satisfied or satisfied.  So if they were able to keep their implants, the patients were doing relatively well. And then if we look at the same thing  from Mark Meyerson's group, this is back also back in 2013, this is looking at how they managed revision total ankles all with the agility, and they found that about 10% failed  and went on to a second revision. What's really interesting though, is that among all comers, pretty much everybody, so 98% of patients had lucencies on the X-ray.  And again, we similar to the last study, about 70% of patients are reporting good to excellent results. And again, that keyword of tailor subsidence, the patients who had the worst  pre-revision tailor subsidence had the worst outcomes after revision with this agility. And so then if we go into that next phase of time, now we start to introduce stemmed implants  and implants with more robust fixation. And so then we can really start to see over the next several years, how does this impact our outcomes after revision?  And you do see some improvements, but you also see these same themes that keep on coming up. So when you look from a group from Seattle,  you can see they looked at 35 agility total ankles that were all revised to a stemmed implant, a 31% complication rate intra-op or post-op.  The rate of patients who underwent a second revision was somewhat low, only 3% in this case, but then three patients, so about 10% all had tailor subsidence on x-rays.  They weren't revised, but again, you're seeing that tailor's failure after that revision.  Then there were a couple of great studies out of Duke that both occurred in 2019. And I combined them here just because I think the themes really parallel nicely together.  In one series, they had 52 revision total ankles and another 29. Most of those were all revised to stemmed implants. And of those, about 80% were able to keep their revision  implant at all. 10% went on to another revision total ankle. 11% were converted to a TTC fusion. The other really important thing to know is that these patients did improve  in their patient reported outcomes after revision. So they started off not doing well in terms of pain function disability. They did do better after the revision,  but if you look at the delta or the magnitude of improvement that they see from pre-op to post-op,  you're not gonna get the same as you will for a primary total ankle. So we're making these patients better, but it's a key part about expectations.  You're not gonna have that same incredible change that you did from before to after your primary.  Then I'm gonna go to a group from OrthoCarolina, who's obviously done a lot for this. And they looked at 18 of their patients who are revised to stemmed implants.  Of note, typically those patients were actually being revised for tailor subsidence or loosening of the primary. And they identified a 22% revision rate.  Interestingly, that really was only talus only or on the tibia and talus. Really not a lot of tibia only failures that were occurring after the revision.  And again, we see this theme. 40% of the revisions had some type of radiographic lucency or subsidence. And then a lot of them had this progressive osteolysis radiographically.  And then finally, I'm gonna go to a group from the UK where they looked at 29 revisions all performed with two-year followup.  And again, similar thing. They actually had a relatively good survival rate at 97%, but their infection rate was 7% and a reoperation rate of 7%.  So then we start going into the last three to four years. And this is, oh, excuse me, I have one more. So then we have 30 patients here, and this is a different implant  with, again, robust revision fixation, not a stemmed implant in this case. This is the Salto XR. And again, they had a 10% revision rate,  10% reoperation rate in the first five years. Interestingly for these, it's all tibial loosening. But again, you see that very, very high rate of radial lucencies post-revision.  And so then we can actually get into the last few years where we start to have these augmented stemmed implants that we just talked about in the last two lectures.  And so, okay, we have these implants that can help us deal with these situations. How are we doing? Are we doing any better? So the first study I'll show is from the Duke group  where they looked at 28 patients. All had a stemmed tibia on the tibial side, but then a stemmed augmented talus on the talar side. A 40% complication rate though,  and of those, there was 11% implant failure rate. Interestingly, these were all for infections. I know this isn't really an infection talk,  but it's certainly something to think about. These patients are having multiple surgeries. A lot of times they've had multiple prior operations even before the total ankle.  So certainly something to consider. Then I'll show some of our work that we did led by one of our fantastic fellows a couple of years ago who looked at 19 of our patients  who underwent a revision total ankle with modular augmented implants. And at the time of the study, we had 100% survivorship. I'm gonna show you all the fun of follow-up  that happens afterwards. But at the early two-year follow-up, patients were doing well. We were starting to see though, talar subsidence and talar lucencies.  And when we expanded this cohort more recently, we looked at our 46 revision total ankles and most of them were revised with a stemmed or augmented stemmed implants.  Interestingly, the patients who were revised for a tibia only failure actually had very good survival post-revision. About 96% of them were still doing well.  But when you look at the patients who were being revised for failure of the primary implant due to a talus failure or a talus and tibia combined failure,  there was a much higher failure rate going on to a second revision. Something like 26% in the talus failures, 20% in the combined. And of those talus failures that survived,  I say, quote unquote, survived because nearly 30% of them were subsided or failing on x-rays, but just hadn't gone on to a second revision yet. And so when we put this all together,  this is what I think we can say. One, we know that revision total ankles are coming if you're not seeing them already. Two, patient expectations are gonna be key.  This is a great area, I think, for future study where patients may expect to be revised to a total ankle, not a fusion. And I think it's good to counsel them.  There are opportunities for them to get better, but it's not gonna be the same as after the primary. We do see that these modern stemmed implants,  including the use of modern stemmed augmented implants are playing a key role and seem to be really beneficial on the tibial side. But the three kind of unknowns  or three points for contention, the talus continues to be a problem. And this is true of every single study. And that's true of the study, the historic, more than 10 years ago.  And it's true of the studies that have come out this year. We really struggle with the talus in the revision setting. And then even in those revisions that quote unquote survive,  there's still a very high rate of radiographic complications. And so what's the clinical significance of these? We need more follow-up to know.  And then finally, that really links into, we don't really know what happens after two years. Most of these studies have two-year follow-up in the revision setting.  There's certainly limited data so far. So obviously this is gonna be a really important topic for the next several years. Thank you all so much.  Thank you, Jensen, for a great review, a terrifying review, a great segue into our revision talks. So we'll go right to David Pettawitz. Dave is a professor of orthopedic surgery  at Thomas Jefferson and chief of the foot and ankle service at Rothman. He's gonna talk to us about managing tibial bone loss and revision ankle replacement.  Thank you, Konstantin and Jensen and Brian and Carl.  Those are excellent talks and great introductions to us talking about revisions.  These are my conflicts.  Okay, so just a little bit of an introduction. So I do about a hundred ankle replacements a year and the systems that I use are relatively simple.  And the systems that I use regularly are the Cadence, which in full disclosure, I was a designer on that team. I use the Salto and I do use InBone.  About 50-50, I do at a large academic hospital with the other half at a private specialty hospital and they're all done as inpatients with a one-day stay.  And kind of my personal journey has been, you know, I did my fellowship with Roger Mann. I did a mobile bearing star three-piece design starting in 2006.  I used it exclusively for a long time for in which I thought the results were pretty good.  I used a fixed bearing when I sort of wanted more stability or what I thought was more stability. And I added a stem for cases of bone loss or revisions. I used a flat cut talus  when I had some bone stock deficiency or for revisions.  And this worked okay. But now we have many more primaries and many more revisions to do.  And as Jensen's talk really outlined, I don't think we have a lot of guidance on how to approach this. If you look at some of the more recent data, there's not like a lot of studies  and the studies don't have lots of patients. So while there's a lot of level four data,  it's hard to know, you know, where we go long-term with revisions and what techniques are gonna be the most, are gonna provide us with the most longevity.  So we do know that primary total ankle is a challenging procedure, but revision total ankle is even more challenging, right? Bone loss, deformity or soft tissue.  And, you know, we do have to sort of acquiesce that revision is not always an option, but we're gonna talk today is bone loss in the tibia.  And so there are many primary systems, right? Everything from ceramics to, you know, the lateral approach, the anterior approach. There's so many different primary systems,  but there really aren't that many revision systems.  So many patients want primary and have some sort of bone loss, but all revisions do have some bones, right? You know, simply by removing the old implant, you have some bone loss,  but osteolysis is often an issue that we're dealing with.  And if we look at that study that Jensen was talking about, that she was the primary author on, the tibia has failed, but it's most, you know,  it's the taluses that are more concerning. But to focus on the tibia, you know, bone loss comes in many forms. Here's a patient with an old infection over like 15 years old.  And when you go in there, like this is not, this may not be someone who can get an ankle replacement.  So once they have a total ankle replacement and it fails, cause we know it will, and it's because of the tibia, what strategies do we have to solve these problems?  Basic considerations that I think of is, can you replace the bone defect with metal?  And will cancellous or structural grafts suffice? And as Carl pointed out so nicely in the introduction in his talk, we don't have all this stuff, right?  We don't have these easy augments for bone defects. And maybe that's coming, and maybe we'll find some nice materials and ways of stabilizing that'll work well for us.  But currently we don't really have that at our disposal.  So what should our approach be? I think the first is that we rule out infection. Obviously that's the subject of another talk, aspirations, labs, et cetera.  But I've sort of come up with an algorithm for how I think you deal with tibial bone loss. And this is all level six data, right? This is not just opinion, it's completely opinion.  Okay, it's just based on my opinion and my experience so far. So I start with infection. If there's an infection, I think you need to ex-plant and do a second stage revision.  I don't think that's particularly controversial. The DARE procedure, debridement, and implant retention is, I don't think that's mainstream here in the ankle.  But if there's not an infection, the first thing I look at is, is there an adequate or intact medial malleolus? And obviously on the second stage revision, you go there too.  If there isn't, then we need to do an extensive RAF of the distal tibia. Once we've addressed that or don't need to, is there already a stemmed implant?  And if there isn't, then I think a stemmed revision, as many of the cases already shown is a great option with autograft, allograft, biologics, and then RAF of the medial malleolus,  as Carl said, he does in all cases.  If you already have a stemmed implant, can the new implant bypass the old footprint? I think that's very important to assess. If it is, then you can do a longer stemmed revision.  And there is probably a limit to how long we can stem them. And if no, then I think there is a point where you need to graft or fuse with a cage.  So let's go straight to cases.  This is a star that I did a long time ago,  was doing great, no pain. One year post-op, he's so happy, he has no pain. He starts digging for a garden project, jumping on a shovel actually.  And so he gets this medial malleolus fracture.  It looks pretty straightforward.  So I put in these two screws, non-weight burn for six weeks, doing well. This is now two years post-op. He's got this little area here  that I'm a little concerned about, he has no pain. Well, here we are six years post-op. He has all this osteolysis, he has no pain,  but he's got pretty extensive osteolysis on the AP as well as on the lateral. Again, no pain.  So I injected this area with calcium phosphate cement. The guy had no pain, so I didn't know whether this was something I should have autograft, allograft,  do still continue to watch and do nothing. This is what I did. I don't think it made any difference.  Eight years post-op, now nine years post-op, he finally has pain. You can see he has this really large defect in his talus. The tibia similarly does not look great.  A question was asked earlier in the chat, what about injecting these areas with calcium phosphate cement? I mean, I feel like that is just a filler.  I don't think it's an osteoconductive filler. It's certainly a filler, but it's a dead filler as far as I'm concerned, long-term. It doesn't provide the implant stability.  So let's go back to our algorithm. So there's no infection.  I didn't think he had an intact medial malleolus.  He does not have a stemmed implant. So a stemmed revision with the grafting, I thought was pretty reasonable. So I did a stemmed tibia, total talus replacement  because I did not think we could do anything with those grafts, I mean, those cysts in the talus, they were just entirely too large.  The screw did push up the wire when I was putting in those medial malleolus screws. I thought that the tibial component was a little dorsiflex through the cyst.  I did do an ATFL reconstruction into the total talus  and I used allograft plus PDGF.  But just when you thought maybe you had done a nice job, this is crazy. This is three weeks post-op. The guy has placed no weight on his ankle.  And I actually confirmed that the Morse taper was engaged intraoperatively, right? So this is what he has here. And I'm like, oh my gosh, this is great.  This is gonna ruin everyone's week, right? So basically what I did is I bypassed the old length with an additional tower. I filled most of it with metal.  I bone grafted the rest and in paxion grafting, just like Carl described, I did add another anteriorly based medial malleolus plate to reinforce it.  He was non-weight bearing for three months at this point. He's now eight months out. And I did sort of extend some of the screws on that medial malleolus plate.  Let's go to case number two. So this is a 56-year-old police officer, teaches at the police academy. She's 10 years out from ORF of a trimal removal of hardware,  a skin grafting posteriorly from the wound. She's a heavy smoker and she's got a lot of ankle pain. So I obviously confirmed smoking cessation.  I did a cadence total ankle with ORF in the medial mouth.  Okay, we got wound baked down and necrosis anteriorly at three weeks. I assume this was obviously an acute infection. I discussed stage versus dare, but I don't dare do dare.  So we did a washout of poly exchange, exchange the medial malleolus screws and a flap in six weeks of IV antibiotics. And that's the flap on the right. It looks pretty nice.  But deep infection at four months. And you could argue that I maybe should have been a little bit more aggressive with that in the first place.  But nonetheless, our retrospective scope is much better. Obvious loosening and pain. So I removed it. IND spacer, lift up the medial flap,  which incidentally is like the most vascularized anterior approach you'll ever do. It feels awesome when you lift it up.  Six weeks of IV antibiotics, then a period of no antibiotics. And I would kind of go with Carl's thought process, which is, I think these patients,  this is gonna be a really challenging fusion no matter what anyway. We've got a large defect. You can fill it with a cage and do a TTC fusion. But as Jensen also mentioned,  I think patients' expectations have changed. I really do think, because they still want this ankle replacement. So back here to infection. Yes, we did an explant.  We did a second stage revision. Intact, adequate medial malleolus? I don't think so. It's too small, right? So stemmed implant already? No.  So stemmed revision with biologic augmentation. So what we did was a revision total ankle, RAF with long screws. I do like try and get to a second cortex if I can.  This is the revision SALTO implant. This is three years out. She returned to work at the Poliph Academy, no pain. I put that little cloverleaf there  because it's always better to be lucky than good. And I was certainly lucky in this case because this could have gone south in many ways. This is her range of motion,  which I think is really surprising, especially with the flap and the amount of soft tissue reconstruction she's had done there, but nonetheless a nice result. Now, just remember,  the ticket does not always have to be revised if it isn't loose. These are both patients over eight years out from a star. There's a fracture, obviously, in A.  I did grafting in RAF, and you could argue that maybe I shouldn't have, but this patient did fine. No pain also in B, a large osteolytic area.  The argument is that this is aseptic loosening, as we see in a lot of mobile bearing designs. In both cases, the implant should be revised, but I think that an individual approach  to isolated cysts is reasonable.  Go to case number four. Seven years out from a primary SALTO developed cyst in the distal tibia, but this, I think, compromises the stability of the implant, actually.  So let's go back to our algorithm. Intact medial malleolus? No, right? Stemmed implant already? Yes, a small stem, but can the new implant bypass the old footprint?  Yes, very easily, right? So what we did here was we bypassed the implant surface,  and as you can see, that yellow circle, that's the old top of the implant. I also put on PDGF on these cases. I think that doing that is very important  because there's a vascular bone there that I can't really see. This is the last case. It's a cavitary bone loss immediately six years out from an infinity.  And you can see here, really, you can see those medial malleolus screws. That is a real defect. It's almost like just a shell of medial malleolus.  So again, no infection, but not an intact medial malleolus. So we have to deal with some impaction grafting, no stemmed implant. It's easy to stem this to revise it.  So what we did here was we used that, again, a plate, medial malleolus, autograft-packed stemmed salto. And you can see that plate really comes around and stabilizes the area.  And this is really important because if you're gonna impaction graft something, you don't wanna break it even worse because I've had fractures extend up the tibia  during attempted impaction grafting. So you really need to make sure you have sort of time zero stability before you do your impaction grafting.  Is there a role for custom implants?  This is this x-ray on the left. This is one of those x-rays that everyone circles around their division when they're like, holy crap,  can you see what, did you see what came into my office today? So that's what that x-ray is. I don't know who did that surgery, but this is a small study on seven patients  with large tibial or talar defects. There's not a lot on custom implants. I think that there's going to be much more on custom implants as the unique deformities  and defects of tibial as well as talar bone loss continue to cross our desks and we need to find unique solutions for them. So in summary, tibial bone loss is common  in revision surgery. Newer implants will hopefully give us more options.  And this is an algorithmic approach, it's my opinion, but I think it seems logical until we have a more evidence-guided approach. So thank you very much.  Thank you, Dave. I think we all love a good algorithm and I think there was about 65 people that screenshotted your algorithm. I'm sorry about turning my camera  off to screenshot it myself, but maybe you'll send me that slide. But I really like thinking about things systematically and you showed some great cases, so thank you.  All right, our last speaker is Bill McGarvey. Bill McGarvey is, well, you see it right there, he's a professor and vice chair of orthopedic surgery at UT Houston.  He's gonna talk to us about tailor bone loss in revision replacement.  Yeah, thanks, Konstantin.  So four very tough acts to follow, great talks. And I really appreciate being part of this. And as usual, you leave the old guy to pull up the rear  and try and save time and keep us going. But here's some disclosures, one of them very significant. I am a design consultant for one of the implants that you'll see used here.  So I put my first ankle in in 1996, 28 years ago.  And if you look at survivorship and Jensen did an outstanding job of summarizing these reviews of what works, what doesn't work, how they fail, et cetera.  You see these things, they'll last a while, but they won't last forever. And so we're gonna have to figure out ways to make them work. And the secondary or the follow-up to that,  which I think is really critical is that even in the revision literature, they're not always working. And so a lot of this really is not just early design flaws  on some of the implants that were available back in the day, but figuring out what caused these things to fail. Why did it fail? Because that is really the key  in terms of what you need to do to try to make it not fail in the second go-round. Because people don't want a third and a fourth go-round. It makes them angry, it makes them upset.  And we get into other options that they're really uncomfortable with. So as you've just heard in David's talk, a lot of these features apply to the talus side,  even more so than the tibial side. Bone loss, leading to subsidence, could be from poly wear, lytic lesions that could be related to the wear or could be secondary to other things,  including thermal injury that's been suggested as a result of saw cuts that leads to ultimately  a ballooning and disastrous cases of subsidence, aseptic loosening, and even septic arthritis. You've heard of all of those. It's been shown going back to 2010  that a poorly placed ankle replacement can lead to edge loading, which leads to polyethylene wear, lysis, and cysts. And you can see these things in multiple formats  across the paradigm of ankle replacement, starting back in the days of agility and star only, and now making its way into our more commonly used implants.  And they'll follow the rankle pathway. I'm not gonna get into all that biologic mumbo jumbo because you don't wanna hear it at nine o'clock at night  or wherever you are, whatever time it is.  But these abnormal stresses can lead to a significant problem, including buildup of osteophytes, malarial fractures, as we've just seen, but in the talus subsidence,  which is probably the most feared complication. So systemic disease can do this as well. Osteoporosis, infection, rheumatoid arthritis, component malfunction can lead to it.  Some of the early designs demonstrated that subsidence was only inevitable because of the shape of the talus. As you see on the lower right there with this agility component,  it was about half to a third of the width of the actual native talus. And when you cut it, it'd act like a log splitter and just split right down the middle  of the tailored body over time. And it was almost predictable just depending on how much time. So when they do fail, and they will inevitably because these are mechanical devices  and they will not last forever. What do you do? Well, the original FDA solution for this was to suggest that we do something like this. And this is all well and good,  but this touches on a lot of problems. These don't necessarily always heal. And sometimes you're left with this construct staying the way it is or resorbing,  leaving you with hardware failures and bigger problems.  We evolved our techniques and use these things. And these have been alluded to in some of the discussions about tibial failures.  And then we evolved into other options that included actually using implant revision. So you can see this very old ankle implant. This was in for 19 years before a patient came in  and wanted to have it revised. And this is a very old case already because looking at the CT, you can see cystic change on both sides. You can see not much subtalar joint.  So what did we do? We went with custom implant technology back in the day, but you can see here already, you put this implant in and it's already lytic around it.  And there are some significant issues with the mechanics of this, but this was what we had back in the early 2000s and even late 1990s. But the FDA stepped in and said,  no, no, no more custom implants, we can't do that. So then we started thinking, well, what can we do with existing implants? So again, here's what I'll call  a second generation implant failing. You can see the polyethylene wear, the shift in the talus position of it. And so this is where we started to do  using third and fourth generation implants, starting to switch from non-stemmed to stemmed and even incorporating subtalar fusions. Now, this is one that was done simultaneously.  I don't do that routinely and really try and stay away from it because you're addressing the talus from above, you're addressing the talus from below.  Where's its blood supply left to be? And it's really not a good answer for that. So if it starts to subside over time, it's a problem. This guy actually got away with this  or maybe I as a surgeon got away with this, but I try to do these in stage fashion as Brian showed in his earlier talk on primaries,  try and get the fusion of the subtalar joint first, create your bone stock, and then come in and do a primary arthroplasty over top of that. But when the whole thing goes bad,  you're left with this sort of thing, what can you do? And sometimes you just have to make it up as you go along and come up with these creative solutions.  So again, the FDA stepped in in the mid 2000s and said, we can't do these, that's a custom implant, we can't have that, we can't have a bridging subtalar joint.  So let's give you some strategies on what you can do. So I'm gonna start out and we'll kind of work up not truly an algorithm like David just showed you,  but more of just a brief light of ideas and things that are available currently on the market. So this is a patient that I did not do this initial implant on,  but who had done well reasonably for a period of time. She came back and had some lytic lesions around the tibia first. And so I initially treated her and I'm sorry about that,  I don't know why these images aren't projecting well, but I initially did bone grafting and plating to try and preserve her original implant.  You could see here that worked reasonably well for a period of time, but she came back a few years later and said, well, now this is no good again.  And you could see, even on the plain x-rays, you can see that tailor component starting to slip down below the edges of the tailor body. And this is what happened with this implant.  As you look at the CT scan, her cysts have recurred in the tibia and she's got subsidence of the tailor component down into the tailor body, but it's not horrible.  You still have a lot to work with here. And I think that's step number one is identifying what is left and how viable is that. She looks like she's got a viable tailor body  and she looks like she actually has a reasonably vascularized one if you look at the trabecular lines, because there is no significant sclerosis  and while there are some cysts, it's not horrible and it doesn't involve any structural areas that look like it's got a fracture in the sub-tailor joint. So multiloculated cysts,  this demands just basic revision componentry. This is out on the market, relatively straightforward. You can get patient-specific imaging or instrumentation, or you don't have to.  This can be done with basic instrumentation. And so you can revise this on both sides and use what existing tailor componentry there is.  So we did that and she had gone on to do very well.  Subsequent to that,  start seeing more complicated situations. So here's a situation where this individual young man had this ankle replacement.  I'm not sure it was done particularly well to begin with, as you see that there's already posterior liftoff on the tibial side, I'm sorry,  and the talus is somewhat subluxated anteriorly. So as this continued to fail on the tibial side,  he went back to the same surgeon who did this operation and gave him this result. And again, you see that there are some suggestive lucent lines around the talus.  And as you follow this over time, you see that this will continue to progress as it starts to really loosen. Now, the interesting part about this is this may be stress shielding  because the large stem on the tailor component seems to be still well-fixed, but there's resorption around the actual base of that tailor component on the talus itself.  So you can see that well illustrated here. And as this continues to lice, you see that even that large stem starts to become lucent around it. So in this particular case,  his tibial stem was well-fixed. He's a young guy. He's already been through a revision operation and he really wants to try and minimize his damage. Again, with CT scanning,  we see that there's good preservation. And so again, we use basic componentry. Now, I have to question my own decision because as you look at that tibial component,  you could see that on the medial side, there's some lice starting around that. My hope is that inserting that not only the tailor revision component, but the evolution of this  is that this particular brand of component also had a step forward in its polyethylene. And that's a big statement at this point.  Not all polyethylene was the same throughout the 2000 teens. This particular component had non highly cross-linked polyethylene when this implant was put in.  They came out with a highly cross-linked polyethylene that made a huge difference in terms of wear patterns in multiple other joints and multiple other parts of the body.  And it only stands to reason that this should be something that is actually fairly worthwhile. So in following him for the next four years,  there's been no progression of that medial sided lesion. And so does that speak to the polyethylene? Does that speak to better wear mechanics? It's difficult to say,  but it's also a consideration in the wear of these implants.  Moving forward and getting more severe, you can see this is an 83 year old ophthalmologist who enjoys playing tennis and was playing tennis on this ankle.  And he really didn't wanna have another operation. He had pain, subfibular impingement. When he did agree to another operation, it was by another surgeon  to try and do some interval procedures to do subfibular decompression, try and reposition his foot. But ultimately you can see that the poly wear created a metal on metal situation  that caused significant collapse and particularly Taylor collapse through the sub-Taylor joint. So in this particular case, you have to get a little bit more creative.  If you look at this, he's lost not only height, but position. This is gonna be a total revision. And so in this particular case,  CT scan shows that there's really not much to work with on the Taylor side. Yes, head, yes, neck, body questionable. And certainly the amount of body and the solidity of the body  is very difficult to say whether it's intact. So in this particular case, we use again, some standard componentry. You can see that in this particular case,  I augment that not only with cement, but with a technique that was popularized by Steve Haddad. And I'm sure Brian, you probably use this as well with some screw fixation,  some axial fixation from below to create some support, some rafting, if you will. We'll see some more of that as we go forward because my self critique of this  was that this is one of the earlier times that I had done that. I used one screw thinking that I was gonna support this and prevent it from subsiding through the calcaneus.  And so far it has along with the cement, but you'll see how that technique has evolved in my hands. So this is my own patient. I did the agility back in 2004.  You could see that she shows up years later with ankle pain, shortening, subsidence. The lateral is really impressive. You can see that the Taylor component  is now into the calcaneus. There really is not much talus left. In point of fact, the tibial component is resting in what was the talus.  So this is subsided probably about an inch and a half to two inches. In this particular case, it's difficult even with a good CT scan  to appreciate how you're gonna get a Taylor component in there and make this work. And so to Dr. Weatherford's points earlier, a two-stage operation is not necessarily a bad thing.  In this particular case, a three-stage operation wasn't really a bad thing either. So look at the CT to get an idea of what's left  and what you have to work with and then start working. Her height is not gonna work and she's not gonna come out to length and standard fixation. So I put a frame on,  we distract across the site of the ankle and get her back out to what I believe to be her length. And I really don't have any reference other than her contralateral side,  which I use as a height reference from the bottom of the heel to the tip of the fibula to give me a relative idea of where she needs to be. Once I get her there,  I take her back for stage two, which is removal of the frame, application of cement, and then taking what little she has left of her talus,  but trying to preserve any bone stock that I can by fusing tail and navicular, tailor head to navicular and what little posterior body to give something to rest on.  And then stage three is to come back and use again, revision componentry, but this rafting technique that I used more horizontally and obliquely than I did in vertical fashion.  And maybe this is good, maybe it's bad. You see cement in there. There are some off-label uses of metallic wedges as well. Everything, you know, in Texas, we like to say,  just use some bailing wire and duct tape. And that's kind of what you have to do. This gives you a large opportunity to be creative with these patients,  because again, to Jensen's concept, patients have an expectation. They want to have a revision ankle. You put in a primary, knees get revised, hips get revised.  I want my ankle revised. I don't want a fusion. I didn't want a fusion to start with. I don't want one now. There she is, weight bearing. After a period of a couple of years,  could I have centralized that foot a little bit better? Absolutely. But she has a functional ankle and she actually likes it. So it's somewhat of a win.  Second to last patient. This is a patient that I did again, primarily. She has this varus alignment at both knee and ankle. She came in a long time ago and I did this fusion  and she was okay with it, but she didn't love it. And it was problematic because she had varus knees that were failing, but she didn't want to have varus knee operations.  So she had me do her ankle on the other side, her ankle replacement. This did well for a period of time. And then about maybe six, seven years later,  she came back with some medial sided ankle pain. She was seen by my PA who thought it was posterior tibial tendon problem, got her an injection.  She actually felt better for a little while, but then after a period of time, she shows up with this. So to David's algorithm, she's got medial malleolar failure,  but her tibia is well fixed and the CT shows that, but the talus is subsided. Her knees are still in varus. She still doesn't want an operation.  So I have to work with that poor mechanical axis. I go in, fix a medial malle, biologics, as he's nicely proposed, and then come up with this technique,  which I, again, stole from Hadad. And so cement the talus, put a lot more screws coming from vertical, rafting this right up to the base tray  to provide solid fixation from the calcaneus on up and create my own subtalar fusion where she really doesn't have much of a talus and I had to make one.  Now, sometimes you get beyond what you can even make. And this, Brian, looks like your original case that you showed.  And this guy was more than 10 operations in. He had had some cavus foot surgery that didn't go very well. He was walking on the side of his foot.  His talus had collapsed asymmetrically. He hurt, came in looking for an amputation. We talked about that. We talked about some other things.  And he really didn't want to have an implant because he had heard that they were bad news. He allowed himself to have all these operations,  but he felt that implants were bad news. So he didn't want to do that. So he allowed me to do a couple of stages. Again, contralateral views, always your friend.  It gives you what their normal is and what you have to work back to. Again, I'm a little bit of a framophile. Patients hate it, but it's a great tool  for just trying to reestablish your orientation. So we get his orientation back and then we go to work on trying to build him a talus out of, again, some baling wire and duct tape  using some screws here, metallic wedges, off-label use, some cement, just try and get everything back aligned. And to some degree, I do. I get his height back.  His alignment's a little better. His clinical alignment's a lot better. And he's actually pretty happy for a while until this thing predictably fails because the talus is dead.  And so he starts to collapse and you can see it here. You can see the screws now starting to penetrate not only through his talus, but up into his tibia and he's subsiding.  And so now what to do? Because now he's in trouble, but now he doesn't want an amputation because I've given him a salvage philosophy and he likes that. So what do we do?  We try and make him a talus out of his other side. Get some CT scans. We show that the talus is completely dead. There's nothing left. And so at this point, it's crossing the other,  the talonavicular joint as well. So rather than trying to use standard componentry, we go to more customized componentry and use this particular device.  So we create, we implant a standard tibial component. We create a custom tailor component, which fixes not only to the talus, but also across the talonavicular joint.  He's already got a recreated foot and he's actually got this now for about the last three years.  He's not in love with it, but he doesn't hate it. He's happy that he has his leg. He can walk, he can go to work. And this is what you can do if you wanna be creative with these  and you really have to.  It just brings us to situations where we get into things where we just don't really have great answers. And I am currently working with this guy.  I'll save that for another talk in another day.  So talus failures can be exceptional, especially with massive bone loss. Treatment strategies may need to involve the calcaneus as part of your talus.  Bone stock may need to be manufactured, reinforced, or both. And the stability of the implant is key. So reestablishing the joint line is important. Have a kitchen sink approach  because you may need everything that you have plus some things that you have to send people out of the room or out of the hospital for. Thank you.  Thank you, Bill.  I think your talk and everyone's talk really highlights the challenges that we're dealing with. I'd like to thank all our speakers for really thoughtful, really great talks  showing a lot of cases and some of your tips and pearls.  We just have a couple minutes. One question that came through the chat was about vitamin E poly, and I'll give you my take on it.  I tell patients new technology is new,  and we hope it's better. And it's our duty to study it, to determine if it is better.  We hope it's not worse. Vitamin E poly, highly cross-linked poly has the ability to have lower wear rates, less particle burden, less osteolysis.  I think the group really showed you great cases where there's osteolysis in cysts  that are of consequence. And so if we have less of that, or if it takes longer for those to develop, that's ultimately a good thing. But time will tell, so we need to study.  We need to study vitamin E. I'll take one poll from the panel, and then we'll end it.  We showed a lot of cases of failure that needs revision. We showed a lot of challenging cases.  We'll start with Carl. Give me a very quick 10, 30 second answers. How do you determine when to bone graft cysts around the ankle?  Is it a size? Is it a location? Is it both? There's no right or wrong answer. But Carl, how do you make that decision? Bone graft versus revise, or just bone graft versus watch?  Yeah, a patient comes in five years, and they have no pain. And you take an X-ray, and there's a cyst. You get a CAT scan. The cyst looks much bigger.  We all know that the X-ray looks bad. The CAT scan looks worse. And in real life, it's massive. So how do you decide when to bone graft them?  Yeah, I mean, obviously, there is some literature on this from our institution. The bigger they get, I think the more difficult it can be to be successful with that.  Obviously, the bigger they get, the more it's gonna compromise implant stability.  They don't have pain, and they don't want an operation. They're obviously gonna get a CT scan. That's how I'm gonna determine the size.  And then I'm gonna see them in four to six months and re-CT them. And if it gets bigger, I'm gonna tell them,  we need to get on this before I can't solve this. And that's kind of, I don't like to push people towards surgery, but I also want to have options for them, so.  So Brian, are you bone grafting cysts or are you cementing cysts? What are you doing for asymptomatic cysts? So similar to Carl, I mean, it's hard to convince someone  who doesn't have pain to have a surgery, but the cyst is increasing, particularly around the medial malleolus. I'm bone grafting it and then reinforcing it with metal.  I'm not usually typically using cement in just for just a cyst without a revision ankle.  So Jensen, do you think location matters? Do you treat tibial cysts different than tailor cysts?  Probably does, but I think it depends also on your implant. I think that what's really interesting is that with some of these stemmed implants  and the couple I've had to go back for, for re-operations early on, I'm amazed that the implant's still completely stable. I'm shocked, honestly.  And so I think if you have a very robust fixation,  you may be able to get away with grafting in a successful place, but in an implant that may have less robust fixation, unfortunately it may compromise.  And so my bet is that it's probably worse on the talus than the tibia,  but we'll have to see.  So Dave, have you ever played a game of chicken with a cyst? Have you ever just stared a cyst down, watch it get bigger, and then it stops getting bigger, and then it never changes?  Or are you jumping and bone grafting them right away? Yeah, I mean, so there are people that I've just watched for a really long time and I've been like,  because they've insisted on not having surgery. I liked your comment, Carl, about how let's try and address this until we get to a point that I'm not gonna be able to.  My thought is that I wait, I pick it out of nowhere, but maybe from the tumor guys, I say, if it encompasses 50% of any fixation surface, I'm gonna graft it.  That's kind of what I tell patients because I don't know that I have a solution if it doesn't work, like if they continue to get worse. So I don't know that there's a right answer,  but I don't do this calcium phosphate stuff that I showed in that one case. I found that that was just a waste of time. All right, last question, Bill.  You showed you've had a lot of experience with a stemmed implant. I'm sure you've passed the six millimeter drill through the subtalar joint many times.  Do you bone graft the drill hole and do you think the drill hole causes cysts in the talus?  I don't bone graft the drill hole.  I will occasionally cement it if I'm dissatisfied with not only my fixation, but also if there's any concern about surrounding infection  potentially leading up there. Do I think it causes cysts?  I really don't because typically the stem or peg on the talar component is actually going to fill that hole. And so the poly has to get down around the bond  and down into that space. So I really don't think that that's an F factor at all in terms of that cyst formation.  All right, well, thanks everybody. Thank you for your time. Thanks to the panelists for giving up your time and to the attendees. We've answered everyone's questions.  So that's perfect. This was crystal clear. Everyone's ready to go. If you have other questions, please reach out to us individually or we hope to see you in Vancouver.  Thanks very much.  Thanks, Konstantin. Thanks everybody. Thanks everybody. Thanks Konstantin. Thanks everybody. Great job.

Video Summary

The American Orthopedic Foot & Ankle Society (AOFAS) hosted a webinar titled "Dealing with Bone Loss and Total Ankle Replacement" moderated by Dr. Constantine Dimetricopoulos, featuring a panel of experts: Dr. Jensen Henry, Dr. David Pedowitz, Dr. William McGarvey, Dr. Karl Schweitzer, and Dr. Brian Weatherford. The event covered various aspects of managing bone loss in primary and revision total ankle replacements, emphasizing techniques, technologies, and outcomes.<br /><br />Dr. Schweitzer discussed the challenges of tibial bone loss in primary replacements, stressing the importance of restoring the joint line and achieving stable implant fixation. He highlighted the need for modular systems and the use of stems and keels to improve outcomes, pointing out that impaction bone grafting and patient-specific instrumentation can be useful.<br /><br />Dr. Weatherford addressed managing talar bone loss, emphasizing a case-by-case approach that often involves secondary operations. He recommended using cement and robust implants, sometimes freehand cuts, to ensure stability, especially in cases with compromised bone quality.<br /><br />Dr. Henry reviewed the literature on revision total ankles, noting an increase in cases and the importance of modern stemmed implants for better outcomes. She identified talar subsidence and loosening as recurring issues post-revision, suggesting that patient expectations need realistic management.<br /><br />Dr. Pedowitz provided an algorithmic approach to tibial bone loss in revision surgeries, favoring staged procedures and biologic augmentation. He shared several case studies illustrating the effectiveness of these strategies.<br /><br />Dr. McGarvey discussed options for dealing with severe talar defects in revisions, including custom implants and creative solutions like the use of cement and screw fixation for supportive structure.<br /><br />In summary, the webinar emphasized the complexity of managing bone loss in ankle replacements and the importance of individualized treatment plans, advanced implant technologies, and thorough preoperative planning to optimize patient outcomes.

Asset Subtitle

Moderator: Constantine Demetracopoulos, MD
Faculty: Jensen Henry, MD; William McGarvey, MD; David Pedowitz, MD; Karl Schweitzer, MD, Brian Weatherford, MD

This webinar will address the challenges of bone loss in primary and revision total ankle replacement (TAR). Our experts will share how they evaluate patients, plan for surgery, and manage complications that can arise when performing TAR in patients with bone loss on the tibia and talus

At the conclusion of this webinar, you will be able to:

Properly assess patients undergoing primary and revision TAR for adequate bone stock on the tibial and talar side
Develop treatment strategies to overcome the challenges imposed by bone loss on the tibia and talus and gain insight into the technical aspects, pearls, and pitfalls of performing these surgeries
Identify the common complications that can arise in these cases and how to manage them postoperatively

Funding for the 2024 Foot and Ankle Focus webinars is provided by the Orthopaedic Foot & Ankle Foundation, supported in part by a grant from Stryker.

Keywords

AOFAS

webinar

bone loss

total ankle replacement

Dr. Constantine Dimetricopoulos

Dr. Jensen Henry

Dr. David Pedowitz

Dr. William McGarvey

Dr. Karl Schweitzer

Dr. Brian Weatherford

tibial bone loss

talar bone loss

revision surgeries