Operation FUBAR: Eight Challenging Hips with Nick Mast

What do you do when the foot slips out of the traction boot mid-case — and a manageable periprosthetic fracture becomes a femur in pieces? Dr. Nick Mast has an answer, because it happened to him.

Nick Mast, a hip and pelvis surgeon in private practice in San Francisco, trained under Joel Matta at the Hip and Pelvis Institute in 2007–2008 and completed hip preservation training in Europe. He's also a second-generation surgeon — son of fracture-surgery pioneer Jeff Mast — and his practice runs heavy on the cases other surgeons send away: complex trauma, revisions, non-unions, and malunions. For this Operation FUBAR episode, he brings a career's worth of them.

The case series spans a 35-year-old malunited both-column acetabular fracture with protrusio (in a yoga instructor), the reverse femoral-head grafting technique he learned from Frédéric Laude in Paris, bilateral Crowe IV high hip dislocations, converting a failed PAO in a Perthes hip, post-traumatic arthritis with intrapelvic hardware, geriatric acetabular fractures treated with fix-and-replace, simultaneous bilateral Perthes replacements — and the recent one: an osteoporotic periprosthetic fracture revision where the foot came out of the boot and the leg fell, comminuting the diaphysis mid-case.

The most valuable part may be what happens around the surgery: how Mast keeps a room calm by lowering his voice instead of raising it, the pack-the-wound pause he learned from his father, the mid-case calls to trusted colleagues that produced the solution, how he reads bone quality on a plain radiograph (the "third-third-third" rule), and why his practice has shifted toward French-paradox cementing. For anterior approach surgeons, fellows, and residents, this is a masterclass in complex hips — and in composure.

⏱️ Chapters:
00:00 What Operation FUBAR is
01:01 Introducing Dr. Nick Mast
03:06 A both-column fracture, 35 years later
06:05 Restoring the hip center in protrusio
08:46 The reverse femoral-head grafting technique
13:27 Reduce, reuse, recycle: step by step
17:29 Bilateral Crowe IV: who needs a subtroch?
19:34 Low, small, and medial — the dysplasia mantra
21:09 An SROM for ninety degrees of anteversion
24:05 Converting a failed PAO in a Perthes hip
27:05 Intrapelvic hardware from the front
29:08 Geriatric acetabular fracture: fix and replace
33:37 Bilateral Perthes, done simultaneously
35:21 The hardest call: length in unilateral Perthes
37:33 A periprosthetic fracture goes FUBAR
40:56 The foot comes out of the boot
43:59 Staying calm when the case falls apart
46:34 Pack the wound, phone a friend
48:55 Reading bad bone; the case for cement
51:39 Advice to a younger Nick Mast

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This podcast is intended for educational and informational purposes only.

The content discussed does not constitute medical advice and should not be used as a substitute for professional judgment. Clinicians should rely on their own training, experience, and clinical decision-making when applying information from this discussion.

#AnteriorHipFoundation #AHFPodcast #OperationFUBAR #TotalHipArthroplasty #THA #AnteriorApproach #HipReplacement #AcetabularFracture #PeriprostheticFracture #Dysplasia #CroweIV #Perthes #NickMast #OrthopedicSurgery

Transcript

Joseph M. Schwab 0:21

Hello, and welcome to the AHF Podcast. I'm your host, Joe Schwab. Before I bring my guest in, a quick word for anyone who's new here on what Operation FUBAR really is. We all know the old military slang FUBAR, effed up beyond all recognition. Use whatever version of F you would like. Well, the whole point is this: we set the highlight reel aside, and we talk about cases that go sideways, the complication, the salvage, the operation that just didn't go to plan, because every surgeon has them, but almost nobody's willing to put one on stage. And in my experience, those are the cases that we learn the most from. So the deal is simple. We put a real case or multiple cases on the table, walk through how it came apart, and talk honestly about what we'd do differently. And I couldn't have picked a better person to do that with. My guest today is someone I've known for years through the Anterior Hip Foundation and someone I'm genuinely lucky to call a friend, Dr. Nick Mast. Nick is a hip and pelvis surgeon in private practice in San Francisco with about as serious a pedigree as the field has. He trained under Joel Matta from 2007 to 2008 at the Hip and Pelvis Institute, where he did probably well over 100 anterior approach hips before most of us had even heard the term. Then he went to Europe for his hip preservation training with surgical giants. He's also a second-generation surgeon, son of Jeff Mast, a true pioneer in fracture and reconstruction surgery. And these days, his practice runs heavy on complex trauma, revision, non-unions, malunions, the cases other people might send away, which, for this conversation, is exactly the resume you want. Nick, welcome to Operation FUBAR.

Dr. Nicholas H. Mast 2:18

Thanks, Joe. And, uh, yeah, I really wanna thank you. That was a very nice intro. Um, I- my father used to joke about like, uh, you know, excellent surgeons and excellent skill in the OR comes from lots of experience, and lots of experience comes from, you know, some bad judgment here and there. So I guess this is the perfect, uh, opportunity to kinda talk about challenges, and so I'm glad you're putting this little talk together

Joseph M. Schwab 2:46

No, that's, uh, I really appreciate it and I, I, I see, uh, no reason why we can't just dive right in.

Dr. Nicholas H. Mast 2:53

I pulled together a lot of, uh, cases here that, um, while not all of them went, you know, horribly wrong or had challenges, they definitely pre-presented some unique stuff that I had to think about beforehand. And so we'll just dive right in with the first one here. So, you know, we start off with some of the more straightforward problems, and we'll get more complex as we go. But this was a 69-year-old female. She had a re-remote healed both column acetabular fracture, um, you know, it was over 35 years ago. And, um, Joel and I looked at this case, uh, you know, over the years. We've seen-- I've presented this case a few times, and, you know, I-- Whether it's se-secondary surgical congruence or whether it was a transverse, uh, T, uh, you know, I'm not sure. Uh, but what you can see here is you can see that there was, uh, disruptions of both columns. So there's a both column acetabular fracture, um, with a protru-residual protrusio deformity. And the challenge with the protrusio deformities is typically the trochanter's sucked up against the lateral ilium, and it can make mobilization very difficult. And other things that I think, you know, we ought to be very cognizant of in this modern age is, um, a lot of the AI-driven imaging that we use during the course of the case to tell you about leg length offset and cup position are gonna be largely useless because they're gonna be relying on things like the trans teardrop line or the trans ischial line, and these things are obviously distorted here. You can see that the teardrop has been moved proximally, that the remaining ilium that's intact is actually the lateral portion that's in contact with the neck as opposed to the, you know, uh, typical roof that you would typically Uh, note. So really the only thing that we have as a really static reference is the SI joints, and so that's kinda what I used here. So, uh, you can see the... when we do AHF

Joseph M. Schwab 4:48

By the way, uh, Nick, am I right in thinking that she was treated conservatively at the time? It doesn't look like there was previous hardware in place that's been removed

Dr. Nicholas H. Mast 4:58

She was treated in traction for, you know, I think a few months, and then, um, yeah, this is what her residual was, and she left it for thirty-five years. And actually, interestingly, she went on to become a yoga instructor as a means of maintaining whatever motion she could and keep her functionality. So this is her life. Um, she didn't have much motion of that left hip, obviously, but she managed to deal with it in, as best she could. Um, yeah, so anyway, you could, you know, as part of any sort of complex acetabular deformity, I, I either get a CT scan or Judet films. Uh, these are the Judet films. Judet, you know, obviously, this is the iliac oblique, and for those who are joint trained who may not be trauma trained, this is a great way of assessing the posterior column. You know, you can see that the posterior column is intact, healed, but it's malunited. And here's the anterior column, and again, you can see the anterior column is healed, but again, mal- malunited. And, uh, so this was enough for me to know that, you know, we've got intact bone stock, intact columns, enough to put an acetabular component in, but we have some problems of where to put it. And, uh, so the surgical strategy here is like the same as I would do with any other cases. One, you wanna restore the hip center, and then if you build out the femur correctly, you'll match the leg length and offset. Um, so in this case, that was sort of the plan. And in order to get, um, exposure correctly, I do a few little tricks. One is I do my neck osteotomy under fluoro, so that helps me guide where I am because the anatomy's distorted. And so being able to, uh, you know, use X-rays is just a great tool to make sure that you're starting the case off correctly. And then intraoperatively, I use the SI joint as a reference for leg length and offset as opposed to the ischium or the, the teardrop. And then, um, another adjunct of the anterior approach is be able to place your screws under fluoro because, again, anatomy's distorted. Who knows if you're gonna put the screw into the, you know, into the pelvis or into the sciatic notch inadvertently? So being able to do that under direct fluoroscopic control is really helpful So, you know, interop, it's proceeds in the usual fashion. We're reaming like we normally would. I use a slightly larger cup when we're doing a petrusio, and again, we're trying to lateralize that hip center. So you can do a lot of little tricks. You could use a rim fit and back, uh, fill graft. In this case, I just went with a little bit of a jumbo cup technique, um, and got it in place, put my screws in under fluoro. And you can see here that I did a pretty good job of getting our length correct, but we're still deficient in offset. But I was able to make up that offset, or at least the global offset, by increasing to a high offset stem. And in that scenario, um, you're improving the abductor lever arm, which isn't bad. Um, the center of rotation has gone medial, so actually, um, this could result in a, a pretty functional hip, and, and that's what we got out of this case. And so, you know, again, this case demonstrates, you know, the typical landmarks that you normally would use. You gotta make some considerations. You might have a little bit more of an offset stem available if you aren't able to fully, uh, reestablish your global offset. And, you know, I think if you-- if that term is new to you, when I'm talking about global or total offset, you know, I would revisit. There's some great lectures through the AHF on, you know, what offset means. I think Joel's talked about it numerous times on, on, I think, on this podcast, if not on, uh, some others, where we talk about, um, you know, the, the offset as it relates to the anatomic offset and the femoral offset, which is the center of rotation to the, uh, anatomic axis versus the, um, you know, global offset, which is sort of the relationship of the femur to the pelvis Um, this is something that, you know, this technique that I show next, I, I have to give great credit to a guy named, uh, Frederick Load, who the first time I saw this just blew my mind, because I had come from a different school of thought on this, and he changed how I thought about it. And this has been sort of, for me, a, uh, a workhorse technique for getting hip center correct. And so this was a patient with, uh, a, you know, crow toe dysplasia bilaterally. And so if you can see this, he has a unique pattern of wear. So this is, um, not-- may or may not be dysplasia, might have started off as dysplasia. But what we're seeing now is his profound arthritis has worn the bone away in a pattern that ver- is, is very much like a, a very severe dysplasia. So it's created a big defect in the ilium above the, you know, uh, above the true acetabulum. And this is, uh, the head wants to fall into it. And so when we're doing these kind of cases, again, the surgical strategy is to put the hip center correct and then rebuild the femur the way it's supposed to be. But, um, if you do that in a unilateral setting and we got a bilateral disease, what we're gonna end up with is a leg length inequality. So something I learned from Joel was a simultaneous bilateral procedure, and this becomes then a simultaneous bilateral procedure with a goal of, uh, again, fixing the hip center correctly. And, and there's a bunch of different strategies out there. There are augments, things like that, where people advocate. In my hands, uh, when we're doing a primary hip replacement, one of our best sources of structural, uh, support is actually the, the native femoral head as it comes out. It can be cert- uh, used well as a graft. So templating, you know, this is my plan. I could recognize that by putting the hip center correct, I'm gonna end up with a big defect above the acetabular component. And this is my strategy, as I talked about. And in trop, so we take our fluoro spots during the course of the case. Um, you can see that literally the screw is going through the cup right at the point where the, uh, the roof sort of departs. And so without, uh, appropriately addressing that, you can see that this cup would very easily, on weight bearing, fall into the, uh, the defect above the cup. And you can see this best on the iliac oblique. You can see the, the defect here. Okay? So, um... Go ahead.

Joseph M. Schwab 11:13

Um, is it, uh, you, you had that first fluoro shot with a cup in with no screw. I'm assuming that that cup was reasonably stable, at least at that moment between the anterior and posterior columns, uh, as you were putting that in. Is that correct? Is that a correct assumption on my part, or was this cup a more, um, uh, more mobile than I would give it credit for?

Dr. Nicholas H. Mast 11:35

Uh, I-- you're exactly right. And I think this technique emerged largely, you know, this sort of reverse grafting technique, which you're gonna learn about, emerged largely with the advent of the newer generation high-friction coatings that you've s- we've seen in the marketplace. Because early on, I think, you know, the old poro coats and other things like that, you would've tried this technique, and you would've had an unstable cup. It wouldn't have stuck at all, and you'd be really working to get this right. But the newer higher friction coating, which I believe this was a Gription cup from DePuy, but there are a bunch of them out there, and the nice thing is you can get that early provisional stability between the, the columns. But this is also... I've seen this as a downside for these new components because people will commonly assume they have a stable component until the patient starts walking on it, and then it'll fall into the position where, you know, you would expect. So you get the false sense of security sometimes. So really, I rely on the, the radiograph, and, and Joel and I talk about this, uh, y- 'cause he helped me out in the last, uh, when we gave a lecture on this, um, is that kind of look at it like a cen- lateral center edge angle. So where the, the roof departs from the cup, you know, if you've got about 20 degrees, well, then you're probably gonna be okay. But if it ends up being, like, zero, like in this case, you probably ought to do something to add structural support. So, um, yeah. So in this case, uh, a little graft goes right in there, and that's what it looks like, and it's fixed with a single, uh, 3.54, uh, fully threaded cortical screw. And since it's a bilateral case, we do this on both sides, and the patient's weight-bearing is tolerated out the door the next day. So it ends up being a really, you know, fun case to do and get to be artsy and get the angles correct of your screws and make it pretty. Um, I love fl- fluoro for that, so

Joseph M. Schwab 13:24

nothing wasted, right? You get to use, reuse

Dr. Nicholas H. Mast 13:27

nothing wasted. Yes, it-- yes, so in San Francisco, we got the, you know, reduce, reuse, and recycle moniker for everything, and so here it is, reduce, reuse, and recycle in San Francisco. Um, so here's how it looks if, if you wanna see it on a sawbone so you can really understand it. I mean, this is the surgical strategy, and this is how I employ it every time now, is that the head you can see here is sitting in the false acetabulum. So you make your neck cut, you remove the head, and you immediately caliper the size of that head, and you go right back in with the same size reamer. Now, you put that reamer right back into that false acetabulum. But again, you're not reaming into the false acetabulum. You're using it to decorticate, using it to get to the punctate, what we call paprika sign, right? Where there's little punctate bleeding in the bone. So you're just hitting that sclerotic bone just enough because you're preparing the bed for a graft. If you go too deep, you're gonna create more of a defect, and you're gonna have to have a larger graft. Plus, you're gonna lose some of the structural support of the, the sclerotic bone there. So all you're really trying to do with this first reamer is you're trying to just get-- prepare the, the host bed. Then you just take that same reamer, and then you redirect it medially, okay? And that's how you get between the columns. Now, you will upsize that reamer a few millimeters until you get that good columnar fit, and then you put your shell in. But you can see that big defect up there. So usually, you can put your graft in at this point, but if you do that, the risk is as you tamp that graft in, you're gonna pop your cup out. So what you do is you put at least one screw in provisionally, and just one of the things I would caution you is that big screw that I put in, you gotta be careful about tightening that thing all the way down, because as you tighten it down, it will shift your cup. So usually, I will tighten it almost all the way down, you know, just sort of hold that cup in place while I put my graft in, and then at the very end, I'll tighten everything down really well. So, um, we get our provisional fixation between these two columns. Then I take the femoral head, and this is a little foam diagram of what the femoral head looks like. I draw the hemisphere on it, and then depending on if we go back here, we can see from pretty much where those arrows are, I gotta do, uh, an entire hemisphere of that, uh, graft. So what we do is we draw it all the way out, and then I draw a second line, uh, that demonstrates the thickness of that, and if you cut towards the, uh, center of rotation of the ball, you'll end up with a graft that generally fits right into that hole. And so that's been the technique. It's usually pretty quick for me. It takes about, uh, ten minutes extra on the case, and the only tools necessary is a small frag set, which pretty much every center has. So, um

Joseph M. Schwab 16:04

And do you tamp that graft in place before

Dr. Nicholas H. Mast 16:07

Yeah, that's kind of the, the technique. Yeah, so the older techniques which was described for this, uh, was you put this, you know, graft in, and you put a bunch of screws and then ream into the graft. And the problem with that is that commonly you're testing your fixation when you're reaming. You know, y- the f- I don't know m- how many times I've done that older technique, and I've spun my graft right out of the acetabulum once the, uh, reamer engages it. So it's like, uh, this technique, you know, you kinda put everything in first, and then you tamp that graft in. And what I've found in my own practice, having done now over 20 of these, is that we get very little graft resorption, and I believe it's because we are putting-- you know, tamping that graft in, so it's loaded, uh, before we put our screws in. And by doing that, I think it, it, it's more likely to incorporate than the older technique, which sometimes, you know, you would shift that graft, and it might not be in a position of loading, and you might not perceive that you're loading that graft, so, uh, it, it resorbs over time,

Joseph M. Schwab 17:06

Hmm. So interesting

Dr. Nicholas H. Mast 17:07

So this is a, yeah, solution, and, you know, a bunch of people out, out there are starting to c- uh, show some really nice cases using this technique. But I think they all go back to, to the, the-- one of the grandmasters of anterior hip, which is, uh, Frederic Laudin in Paris, who originally showed me this technique back in, that was 2009, I think, so. Um, so this is a high hip dislocation, so a lot of the same techniques again apply here. Again, trying to get the hip center correct and then, um, and then sort of restore everything based on that. And, um, so the challenge with, you know, high hip dislocations, Crow IV, is they come in all-- There's a big spectrum. I mean, the ones that are, are easier, in my opinion, are the ones that are more flexible. So when you do your clinical exam on these patients, you know, the patient that has a lot of range of motion, you know, an arthritic hip, but a lot of range of motion. I'll show you this X-ray, for example. Um, this left hip in this, uh, in this AP radiograph, the left hip was actually quite mobile. The right one was very stiff and, um, you know, the right one's a little bit more arthritic, but that left one, she's been very mobile for many years. Those are the ones actually you don't have to get too worried about doing a subtrochanteric osteotomy, at least in my experience. You, you're gonna be prepared for it, but many times you can get away without doing a subtrochanteric osteotomy because they already have a lot of motion. Now, it's the ones that, that have been operated three or four times. They've had a trochanteric advancement. They've had, uh, VRDO, other types of procedures. The problem with those is they tend to have a lot of scar, in which case those I- you really have to be more cautious about lengthening because, you know, the surrounding tissues are gonna be encapsulated in scar. The neurovascular structures are gonna be encapsulated in scar. They'll be a lot less tolerant to lengthening. So those I'd be very, uh, quick to do a subtrochanteric osteotomy. Anyway, so this is a case, so again, bilateral disease. Um, in this case, she's been dealing with this leg length inequality for quite some time. I'm not too worried about trying to correct it all in one go. So, uh, the goal is to restore at least the most painful and stiffest hip first, which was her right side. And so, uh, in this case, proceeded just similar to the last case, um, you know. Interestingly, once I got an internal rotation view on the table, you can see how everything kind of falls back into place. So this serves as our sort of, uh, ipsilateral template for what we're trying to accomplish in terms of restoring leg length and offset. So this is the idea, is to put her back kinda where she was. Um, again, she's a little lateralized here, so I'm gonna accept reducing some of that total offset. But again, I wanna keep that, uh, femoral offset about the same So again, putting a, going s- low, small and medial. That's sort of the key. That's your mantra when you're doing a dysplastic case. Go small with your cup, go, stay low and go medial. And so by doing that, you know, got pretty secure case. You could argue here I didn't need a graft because, you know, again, center rotation is well medial here, but I went ahead and put a graft in like I did in that last case, and, that's the result. And, and in this case, you can see that that side wasn't, didn't have a whole lot of distorted anatomy. I could use a very, straightforward primary stem for this and, yeah, get a, a very good result, and it wasn't that complex, a very straightforward case. Start to get on the left side, we have a lot more issues to deal with and, you know, the... Again, neck cut under fluoro really helps, but reaming under fluoro, you're going to go low, small and medial, and it's amazing how little bone you have down here and how distorted. But the use of X-ray really helps. Again, there's so many of these cases that I think I'm going to be able to get a 48 cup in and you better be ready to go all the way down to 44 and even 42 for your cups, which means you're using 22 heads. So it gets, you know, gets pretty challenging to do these, these high dislocations Um, you get the cup in place, put a few screws in, um, so we know I have a cup s- that's stable, and she was highly mobile, so in this case, uh, prepping an SROM. Now, and why did I use an SROM here when I used a primary stem on the other side? An SROM here gives you a lot more rotational control, and as we know, when we're dealing with, you know, dysplasics and the more severe dysplasias, you're gonna have torsional abnormalities that correspond on the femoral side. So she had well over ninety degrees of, uh, of anteversion, so being able to dial that back is an important part of the case. And so in this case, the SROM was a good implant to do that, and that's our final result with a twenty-two head. And again, no subtrokin- trochanteric osteotomy was needed. And, uh, here's her post-op result, and at one year. Neuro- neurologically, no issue. Woke up fine, no issues there. So yeah, it's a, a very straightforward case, um, using the anterior approach. Um, but again, uh, I've run into similar high dislocations where I've been forced into a subtroch because there's just too much tension, and that's an intraoperative clinical decision that I make. You know, it's... And usually it's, I just go for about two centimeter shortening, two to three, and, um, I just go with that, and that's been my solution there. Um, I use a double, double oblique osteotomy for that, and, uh, sometimes I will dial off torsion by doing my first cut, um, with the, um, saw and then fixing the rotation to the second cut with the saw parallel to the first cut. So you can take a wedge out that's of two, two different obliquities, but the final two components come to- uh, two femoral fragments come together, uh, and line up perfectly.

Joseph M. Schwab 23:01

And, and one of

Dr. Nicholas H. Mast 23:02

You were gonna ask a question? Sorry.

Joseph M. Schwab 23:04

Sorry Yeah. One of the things you mentioned upfront was sh- that she had quite a bit of flexibility on this left side before, uh, uh, you know, certainly much more so than on her right side. How was her flexibility after this with, uh, with the lengthening that you gave her and with the new hip center?

Dr. Nicholas H. Mast 23:20

Well, she was pretty tight initially, and in fact, her IT band was quite irritable after surgery. Um, we were able to get through that with PT, and somewhere around three to six months, she was, uh, feeling very good and feeling very even on the legs and, um, flexibility was returning.

Joseph M. Schwab 23:36

Yeah. And that was something you g- did you talk to her about that ahead of time, about how she might actually lose a little bit of flexibility upfront, or not so much?

Dr. Nicholas H. Mast 23:45

I had no clue what was gonna happen postoperatively in terms of the range of motion, but I, I knew she was painful and I, I would expect that the pain was gonna improve. I-- It was hard to predict what her final range of motion was, but she remained very flexible, and so that's, that's good Um, these are some more cases. This one's like-- This one was probably one of the hardest cases that I tackled, um, that I-- and I think it's because I didn't recognize preoperatively what the challenge was gonna be. And, um, you know, this is a, a PAO that was done in our community, but it didn't go so well for the surgeon who was doing it. And, um, uh, you know, it was a Perthes deformity, so these are really hard anyway. He tried to do a surgical dislocation with a trochanteric advancement and a PAO. Um, and he, he had some challenges, but, you know, at, at the end of the day, she-- I think she did a couple years on this, uh, too much problem. But it came time to convert, and, um, so we went ahead and, uh, proceeded, and I think I did this in a staged manner by pulling hardware first, uh, which was this, and then obtained intraoperative imaging, and, um, then I proceeded with the, the total hip. And, um, I think the thing I didn't recognize is on this image, you can really see it, is that the relationship of the walls. Um, the red wall here is our anterior wall, and our green wall is our posterior wall. It doesn't leave a whole lot of posterior wall, uh, to support an acetabular component. And, uh, as I went in and I started reaming, I realized fairly quickly I didn't have much to work with, uh, behind this acetabular, uh, component, so ended up having to do what's called a medial petrusio technique, which is you kinda intentionally ream through the quadrilateral surface a little bit to put your cup in. And you can see I went about, you know, three or four millimeters into the pelvis with my acetabular component intentionally in order to get stability. And it was, it was a stressful case. I was really worried about whether or not I was gonna get stability, um, but finally did, and I was able to do it without screws and then, uh, proceeded with a Corail implant. Um, but this is what it looks like postoperatively, and, uh, as you can see, that cup's, uh, medial to Kohler or the ilioissial line, depending on your definition. And, uh, the thing that's I didn't appreciate, uh, quite a bit is how much anterior column I was gonna have to take because this prior surgery-- s-surgeon had, uh, retroverted so much, I had to take quite a bit of the anterior column away. That entire red area was removed in order to get clearance so that she could flex her hip. So it was a real, you know, it was a daunting case. And y-you look at it in the pre-op and you go, "It's not too bad." But, uh, if you don't understand the three-dimensional problem, then you can definitely bag yourself, and that's, that's sort of this case

Joseph M. Schwab 26:36

But no acetabular fixation in this one

Dr. Nicholas H. Mast 26:40

You mean extra screws?

Joseph M. Schwab 26:41

Yeah, no screw fixation

Dr. Nicholas H. Mast 26:43

I don't know. This was earlier in my career. I wasn't putting many screws in. I'll use screws more frequently. I think in my hands now, I probably would put screws in. This was, you know, 10 years ago, so I, I was more bold then, I guess. Um, so yeah, I, I went without screws on this one, but that was largely because of Joel's training Um, so this is a post-traumatic arthritis with intra-pelvic hardware kind of case. So this is, you know, an ideal indication for an anterior approach, and so this was my, you know, using, uh, the Levine modification of the anterior approach, which is sort of the intra-pelvic Smith+Nephew. And, uh, so this per- surgeon, uh, used a prior STOP approach. It was done at our local trauma center, and, you know, they did a pretty good job of getting fixation in, although I would argue that their reduction wasn't ideal, and as a consequence, the patient developed post-traumatic arthritis This. So, um, yeah, going through, you know, you could consider just doing this in a primary setting and cutting screws, but I think being facile with the intrapelvic, uh, anatomy extension, and I benefit from doing a lot of hip preservation work, you know, doing the PAO. So this is a very handy approach, uh, for me because I do it all the time for, uh, the PAO. And so being facile with that is, I think, really helpful for anterior approach surgeons because, you know, there's cases where the ball will, you know, the, the trial ball might sneak up along the psoas and end up in, in this space. Um, there are other places, uh, where that, um, that, uh, exposure can be helpful, specifically anterior column deficiencies or revision work. So, you know, it's-- I think it's a good thing for most surgeons to familiarize themselves with. But, um, in this case, the screws come out pretty easily, and, uh, this is the view from my anesthesiologist looking down towards the knee. Uh, and so he's, uh, taking a picture, and so you can see pretty much everything you need to see. You can see the tensors being retracted by the, uh, retractor on the left. You can see the, uh, one at the top of the screen is, uh, just underneath rectus, and then you've got this, uh, lower retractor that's on the inside of the pelvis and the true pelvis exposing the entire, uh, iliac fossa, which is giving us, uh, our exposure for our hardware removal And the rest of the case proceeds very uneventfully. Now, this is probably more of the, the fracture work that I see these days, and, um, I think the things that I've learned here are, are don't underestimate poor bone quality. Um, geriatric acetabular fractures, uh, are a pathologic fracture. They're not a acetabular fracture like we normally treat. So being under-- able to understand that fixation is gonna be challenging, I think that's an important, um, sort of thing to, to, to comprehend when you're tackling these. Um, so this is y- more of the common trauma that I see these days. I'm in a tertiary care center, and it's mostly geriatric trauma. Um, people fall down, and I get referred in. Typically, it's an anterior column or an anterior column poster hemitransverse. Um, so this is an anterior column, uh, pattern with quadrilateral involvement. It was an eighty-two-year-old. She had, like, every medical condition. She sat on the ward of her hospital for two weeks before she even came to me, just trying to get medical clearance. She had renal insufficiency. And so when somebody comes in and they're a couple weeks out from this kind of injury, especially as they're older and they got bad bone quality, you can expect there's gonna be head damage. So I don't even try to, you know, fix them and wait and see. I just go ahead and proceed with a replacement. Um, so this is what it looks like, and when you get your oblique views, you can see that the posterior column is largely intact. There might be a posterior, uh, hemitransverse component, but it's non-displaced. And here we have, uh, the head going with the anterior column, and so that's, uh, a classic pattern for an anterior column fracture. Um, so understanding that and understanding the age and the typical pattern, um, you know, I was like, "All right, well, that intrapelvic Smith Pete becomes a really good workhorse again to get that reduction and, uh, help us get that s- uh, that, uh, acetabulum restored." So, uh, I proceed through that same approach, uh, using a, uh, small push plate on the anterior column, uh, and then, uh Limit-limited fixation, um, is required. You got one screw all the way into the posterior inferior spine, one into the sciatic notch, and all-- one going all the way down into the ischium. I have a separate screw with a washer dealing with that comminuted part of the, uh, the anterior wall. Uh, and, and so this is what it looks like on this, the iliac oblique view. And, uh, then, uh, since we've got a femoral head there that we're gonna do a total hip with, I took the head out, morselized it, and impacted it. Now, when I impacted that, you can tell that I, I tested my fixation because you can see the, the-- we've lost a bit of our reduction. So I did a impaction grafting technique, but I would... I-- In hindsight, I'd probably use a more robust fixation pattern. And, and what I do now is I typically use four or five screws, and I use a lot more of them. Um, so that would be another little pearl that I, I've since switched to here is, uh, because you'll see, you know, we put our cup in. I'm really happy. Looks good on these two views. And you can see where it is post-op, and I'm really happy. But you can see that we've lost our intercolumn reduction a little bit, which means that our fixation's probably not strong enough to support full weight bearing. And her being eighty-two years old, you can't expect her to be partial weight bearing. And she shows up six weeks with a slightly increased abduction, increased anteversion. So the cup has gone into a bit of a hole. Um, so I watched this. Um, by the time she came in six weeks, she was having no real pain. So I just said, "All right. Well, we'll keep an eye out. We'll see her at three months." And at one-year follow-up, it remained stable, and I would say that that cup is ingrown, but it's definitely, um, you know, it was a little touch and go early on. And so the, the, the things I would say for a surgeon who's gonna start tackling these kind of cases, you know, more robust fixation than what I applied here is probably important. And there are some really good plates now, um, that provide, uh, quadrilaterals surface, surface buttressing as well as fixation all the way down to the pubic ramus. I would be-- I would not hesitate to use that. That's what I do more commonly now. And these plates, I think, are made by Stryker, if you're, uh, really wanting to find them out there. Um, yeah, and this is a post-op. And then, uh, you know, again, more complex cases, uh, Perthes. This is a bilateral Perthes case. Again, um, when you're dealing with, uh, restoring anatomy on somebody that has bilateral disease, if you do it in a staged manner, you're gonna end up with an interim period where people are gonna be on one side quite long and the other side off, and it can impair the rehabilitation and the early function. So again, ideal case for a bilateral, you know, approach.

Joseph M. Schwab 33:57

And so this is relatively-- H- what was the age of this patient, Nick?

Dr. Nicholas H. Mast 34:02

This patient was in his forties when he presented with me, and his left side was largely the most symptomatic side. As you can see radiographically, that side's, you know, bone on bone articulation. But since, you know, if I just did the, the left side, I would worry that his function on the right side would still be so s- uh, so poor that it would interfere with his rehabilitation profe- uh, um, potential, and probably we'd be proceeding within three months to do the other side. So in this case, a, a simultaneous procedure was sort of offered. Um, so we can see we have dysplasia. We have a short femoral neck, Perthes deformity. Um, so again, neck cut under fluoro, key for these complex deformities. Um, ream low, small, and medial on dysplasia, and low, small, and medial. And so with a low, small, and medial, when we put that cup in, you know, we have adequate coverage and don't need s- additional screw fixation. Um, and then on the femoral side, a low neck cut facilitates, uh, putting in a component, and then we just roll over to the other side, um, do a contralateral overlay, and then we do the same thing on the other side. And so this patient was very happy with our final result here. Um, challenges with these are, um, length. You know, I don't think there is a harder case than a unilateral Perthes. And I think the hardest problem in the unilateral Perthes is trying to decide where you're gonna put the length. And some guys will say, "I'll split the difference." And I've done that, and I've had patients happy because they're, you know, even, or they feel even. And then I have other people saying, "You over-lengthened me," and I've had some people say, "You leave me short." So I, again, I don't have a good algorithm for this. The other challenge that you're gonna run into is if you don't adequately, like, bump up their offset a little bit, you're gonna have trochanteric impingement, and that's been a challenge sometimes on these. So we get, as you can see on that left side, his-- he still has a bit of what we call the gearshift sign, which is sort of as you abduct, they have no abduction or maybe ten degrees abduction. But if you flex them up and then abduct them, you can get nearly full abduction. So it's this wild thing where the trochanter's impinging. So, um, yeah, it's-- These are challenging cases. But this guy was quite happy with his final result. And I think he still had better range of motion after surgery than he had pre-surgical.

Joseph M. Schwab 36:24

Yeah. I, I think your, your point of the, you know, the unilateral Perthes and the length is, is a really important one. I, I've always found that the more I'm potentially increasing the offset, the less I'm gonna add to the length and vice versa. If I, if I'm doing a really s- you know, minimal offset that they can tolerate a bit more length. And, and so I do think there's a combination in there somewhere, right? That's probably correct for everybody, but it's hard to tell

Dr. Nicholas H. Mast 36:49

I think you're right, uh, 'cause I've seen patients done through a posterolateral approach who have wide, you know, they, they, they've had a bunch offset added, and their length hasn't been added much, but they feel overly long. Or I've had patients where, uh, they've lengthened quite a bit, but they used a standard offset and didn't adequately restore their offset, but the hip has functioned for many years, and they didn't even notice the length issue. So yeah, I think you're right. I think there's a soft tissue sort of element here on these kind of chronic, uh, pediatric deformities that you just have to, you know, you have to have the art and be able to feel what the length and offset, or, you know, what's that doing to the tension of the soft tissues Um, interrupture fracture. So this is the, the most recent f- foobar. So this is one where I think, you know, this is a case that has shift- shifted my practice more recently. I'm doing a heck of a lot more, um, cemented implants now. Um, I think the data out there is showing us, you know, that periprosthetic fracture has a really bad trajectory if it happens in the first six months after surgery, and, uh, I think if you can avoid that, in some cases it's worthwhile. So this is a patient that came in. She's young, 65-year-old, and she's very athletic, um, meaning she's a rower. But, you know, you can see she's got some osteopenia and, um, you know, she's got pretty profound arthritis, both sides. And I wanted to do a simultaneous procedure on this patient, but she elected to go staged. Um, but by the time she shows up, I don't know if you can see this, but she's h- had a r- remarkable progression of her osteoporosis. Um, this is where she was before, and this is where she is now, and this is, like, a year later. I was like, "Whoa." Um, and, uh, yeah, so anyway, so I proceeded with in a stage manner. I used an uncemented implant, and this is, uh, you know, a Karai similar implant, fully hydroxyapatite-coated stem, traditional length with a collar. And in my hands, it's a great implant in the context of osteoporosis. These are good implants for, you know, for bone if you're gonna go Uncemented. But even then, you can see at six-week follow-up, there's a little periosteal reaction at the distal stem tip. And so I was like, "Yeah, she's-- It was probably on the edge of what I should be doing in terms of uncemented fixation." And so, um, I didn't recognize this. This is in hindsight, and you go back to all these, I mean, what could I have done differently? And I look at that and I'm like, "Yeah, maybe that was a sign that I probably should have been cementing the s- other side," but I didn't. Um, and this is how she showed up at, uh, two weeks after surgery as she fell down some stairs. So you look at this pattern and you go, "Eh, it's not too bad. You know, it's, it's, you know, oblique, short spiral oblique pattern." It looks like there is a comminuted lateral, uh, porsus, maybe three fragments, and if you can get it reduced down to two fragments, it's pretty straightforward. But I think you can't discount the contribution of a bone quality here in making the ease of a case. 'Cause if this patient had more normal bone quality, yeah, you get it down to two fragments and then just tease them together and put a clamp on it and get it done. But in this case, uh, as we'll see, things didn't go as well as I'd hoped. So my surgical strategy, line it up on the HANA table under X-ray, put in a screw, proximal, distal, convert it to a, a simple pattern, which is a simple spiral oblique pattern. And I was like, "All right. Great." And, uh, using-- you know, getting my stem out and then putting a ball tip guide wire in, lining it all up, getting my, uh, clamp on it, and then passing my, um, my flexible reamer down. You can see things are already starting to fall apart a little bit here as I'm passing my reamer, um, and I'm going, "Uh-oh." And then I go to place my, uh, Karai revision stem, which is my workhorse for a lot of these, um, as it goes through. Unfortunately, right now at this point is when the foot slips out of the boot

Joseph M. Schwab 40:56

Hmm.

Dr. Nicholas H. Mast 40:57

Intraop. The leg goes flying to the floor in an uncontrolled manner, right there.

Joseph M. Schwab 41:03

Oh

Dr. Nicholas H. Mast 41:05

And, um, so now I've converted a simple pattern into now a multi-fragmentary, uh, complex pattern, and I, I s- I thank my DePuy guys who were there, and they're like, "Yeah, we can be ready." Um, so they had the reclaim on backup. So once you go to... get to this sort of scenario, a, you know, the Karai revision stem is just sort of the philosophy of a s- you know, straight stem and a cylindrical bowed femur. But you have to ha- it has to be able to support weight. You know, it has to be, uh, a load-sharing device, but in this case, we have to go to something that will actually span the area. So the reclaim is what we used. Um, but placing a reclaim from the front when you've got h- a highly comminuted diaphyisis can be pretty hard, um, because the position that you want to place your stem in, um, from the front, i- applies a bit of a, a, a valgus, oh, sorry, varus load to the, the femur as you're trying to, you know, prep the femur. So keeping it reduced while you're prepping it is really hard. And so, uh, had a bunch of struggles with that. You can see, boop, this was not working. So life was getting pretty hellish at this point, and, uh, at this point, I had opened all the way the later- you know, the entire lateral, you know, aspect of her femur. So at this point, I delivered the femur out through the lateral incision prepped it separately, and then, um, because this was not working, and then I just prepped it separately, and then I passed the stem from above. So thinking a little bit outside the box here gave me the, the strategy to prep that distal femur, uh, with the, the reamer, and so that was the solution here, was to just deliver it out, prep the lateral fragment, and, or pr-prep the distal fragment, and then reintroduce everything from above, which I was able to do, and you can see we tapped it in. And then because I was dealing with such a comminuted segment, and it was already pretty low, and you can see how little fixation I have distally, I was like, "I'm not gonna trust that as my entire construct." So I plated her from stem to stern, as you can see here, all through the anterior approach, and thankfully, she cos- comes into my clinic at six weeks, and she's now ambulatory without assisted device. And here she is, I think, so far at, I think she's at three months right now. You can see there's still quite a paucity of proximal bone, but, uh, we've got good distal fixation. But that was one that definitely took years off of my life.

Joseph M. Schwab 43:37

So, so let's stick with that case for just a second 'cause I, I, I have some questions for you that are a little outside of the how did you fix it. Um, so HANA table, uh, foot comes out of the boot. It's known to happen. It's not common, but it can happen. Uh, two questions about that. Yeah. One, what was your reaction as the foot comes out of the boot? And two, what was the reaction of the people you were operating with?

Dr. Nicholas H. Mast 44:06

Well, um, my reaction was, well, I knew something bad had just happened, 'cause all of a sudden the leg... You know, I use a drape that's not, uh, translucent. I use a full, um, you know, drape as opposed to some of my colleagues who use a shower curtain. So if you're using a shower curtain, you know it happened immediately. But, uh, for me, I didn't know exactly what had happened, but I knew something really bad had happened. My feeling was, "Oh, God, I just destroyed the entire femur." And, uh, thankfully, when my circulator noticed the foot was down, I was like, "Oh, okay. Well, let's put the foot in and then assess what we have in terms of a problem." And so we put the foot into the bracket, and we applied a little tension, and then I could see what happened. And at that point, I knew I had a highly comminuted diaphy sis. And thankfully, I noticed that the two, uh, cerclage cables that I put in at the init- index. So right when I go in, I put those two cerclage ca- cables in, one proximal and one distal, just so we avoid propagation of fractures. There was no propagation beyond that cerclage wire. So I was like, "Thank God I had that in there." And so that was my first, um, step. When I saw that, I was like, "Okay, I can make this still work." Um, and then, uh, I think the second thing was just trying to keep everybody else calm in the room. And, and I think one of the big things I've learned, it's got more to do with the soft science of, of life, which is communication. Um, it doesn't, it doesn't help your team if you lose control, you know? Uh, I think one of the things that I learned, and it was a hard-won battle, was the best thing to, I can do is, as I feel my tension go up, is try to slow my, um, my reactions down and my, my speech down and try to lower my tone of voice as opposed to going, "Oh, my God." Is try to bring it down an octave, and I don't know why, but it just, it seems to keep everybody else calm. I don't know. It's, uh, I think it's something you practice, uh, in- throughout your career is, is your response to, to stress, and, uh, you get better at it with time

Joseph M. Schwab 46:18

And was your initial thought, "All right, let's troubleshoot, let's problem solve, let's see what we need to do to get this back on track"? Or does it go to other things like, "How am I gonna explain this to the family? What am I gonna say to her? How am I gonna change her postoperative course?" Things like that. Where, where does your mind go? Or does it go every place

Dr. Nicholas H. Mast 46:37

Oh, that's... Uh, well, your mind goes a million places at once, and I, I'm blessed as I work in, uh, uh, an environment with, uh, some great surgeons. I don't know if you know Robert Maley, Peter Callender. These are good guys in our area. They do a lot of anterior hips. And, uh, you know, I just took a moment. I just packed the wound. You know, I, I did my survey with radi- uh, with X-rays, packed the wound, and my dad used to do this. He's, uh, he was a, you know, trauma surgeon. He'd be in the middle of a both column acetabular fracture, things are not going right, and he would pack the wound, and go out and have a cigarette. Uh, he was, he was terrible that way. He'd just go out and have a smoke. But he, he said you could come back after that smoke, and you, you, all of a sudden you'd see something different, and it would go totally different. And so taking a pause and not trying to hurry through it. So I took a pause at that moment. I called Peter Callender, called Robert Maley, and I said, "Hey, you guys, I have this scenario that occurred, and, um, you know, what are your thoughts here?" And, you know, I, uh, Peter said, "Well, maybe just plate it from the outside first and then see if you can reconstruct a cylinder." And, uh, Maley was like, "Yeah, just prep the distal femur and pod it, and then go from there. Build it all off the, the distal femur." And, um, that's where the solution of delivering the, uh, femur out the lateral aspect of the wound came, was like, "Well, I gotta prep it somehow, and I can't seem to prep it from above, so I'll just prep it down here." And so that was the way to do it

Joseph M. Schwab 48:04

And you talked a little bit about the value of your, your, uh, rep. I think you said it was your DePuy reps, right? Who had, uh, kind of a backup piece available for you. Is that something, uh Were you surprised by that? Is that something you expect? Is that something that, um, that's a relationship you built over time, or was this a surprise that you were,

Dr. Nicholas H. Mast 48:25

This is, yeah, definitely a relationship built over time. Sorry, I

Joseph M. Schwab 48:25

just happy about?

Dr. Nicholas H. Mast 48:29

didn't mean to speak over you, but yes, it is a relationship that's built over time, and so these guys were working with me for many years. And, uh, when we do femoral work, we have a reclaim on backup. That's just one of those sort of rule book kind of things, and I don't check to make sure they have it every time 'cause I, I used to when I was first starting, but n- now I just kind of assume they have it, and I was thankful, so incredibly thankful that they had it on backup, and they were ready to go, so

Joseph M. Schwab 48:55

Um, a little bit more about some of the medical prep. So are you checking routinely for bone mineral density, or are you doing anything for a workup of, of, uh, uh, osteoporosis, things like that ahead of time in patients that you might be suspicious of it? Or tell me a little bit about what you do in those scenarios

Dr. Nicholas H. Mast 49:16

Well, I, I don't think a DEXA scan has really helped me, but when I look at a radiograph, it should-- I should look at that femur and I should see about a third cortex. A third is, you know, the, you know, the medullary canal and a third cortex if you divide it up. And in this case, it was like, you know, two millimeters of cortex with like eight millimeters of med-medullary canal and two. So I knew I was gonna be dealing with it. Um, that's sort of been my sort of take. If I see-- I don't see the typical third, third, third, I, I start to go, "Okay, there's some osteopenia here." And then, um, I have a much lower threshold to do a cementation technique. And I think part of it was, um, that I, I di- I hated the cement, um, tools, and I was trained using surgical simplex and an I-beam construct in my training, and I hated doing those through the front 'cause torsional control was a little bit tricky and, um, and the cement, getting good pressurization, getting good cement mantle was hard from the front because the nozzles and the, uh, pressuration, press- pressurization tools were not designed for anterior approach. So it was never really facile in my hands. So I, I went away And I went almost all uncemented for a lot of years. And then, um, I think it was seeing Jonathan and some of these other guys using, uh, French paradox cementation tex- technique kinda switched my mind about it. And actually, it was, um, Lucas Anderson, who's in Utah, is-- was one of my junior residents. Brilliant guy, just absolutely phenomenal, surgeon, incredible hands. Yeah, he's just, like, doing this thing, he called it a French express, where he assembles the entire stem on the back table and then cements it in, you know, just taps, taps it in, what, you know, line to line. And man, it's, it's facile, it's fast. You don't have to worry about, you know, somebody accidentally bumping the leg and shifting the torsion of the stem because it follows the, the path, the path that you broached. And, uh, the cementation, I think, you know, in the literature is starting to show that this sort of French paradox, uh, cementing technique seems to be viable for the long term. And that's kinda when I said, "All right. This is sort of the technique that I'm gonna start adopting for cementation." I've been very pleased with it

Joseph M. Schwab 51:39

Yeah. Um, and you touched on this a little bit, but I do wanna just kinda ask you, you know, you're, you're, um, well, I, I don't wanna betray anything, but you're, you're close to do two decades in practice, a little under two decades in practice. Yeah. And this case was relatively recent. Um, how do you think a younger Nick Mast would have dealt with this, and what advice would you wanna give him if, uh, if instead of, uh, you know, calling those other guys, he called you?

Dr. Nicholas H. Mast 52:12

Well, I, I think a younger Nick Mast, uh, would've done the same thing that I did. You know, I probably would've called Joel. And, you know, uh, Joel, in fact, I know I did early in my career, I was calling Joel. And I think the biggest, uh, thing that I can encourage a young surgeon to is to develop mentors, um, relationships with senior surgeons who have been in the fold, been in the, you know, in the tough spots before you. And I think, you know, and that's one of the great things about like AHF and, um, these other, uh, you know, um, groups that, that kinda work together. W- you can develop those relationships, and, um, you know, I have plenty of younger surgeons that I've met through AHF who have re- you know, uh, they have my cell number, and they'll text me a, a interesting case or a complex case, and we'll talk about it. I, I, you know, just it's sort of my way of giving back, but it's also, you know, it's... I feel like I'm paying back for all the years that I leaned on, you know, all of my colleagues, probably including you. I think I showed you a few challenging cases in my career. So yeah, this is-- Yeah, so I, I think that's probably the thing i- is to understand that we're-- no surgeon is completely alone. A- and I think the best thing to do is cultivate those relationships so that you have somebody to call upon when things aren't going right.

Joseph M. Schwab 53:44

Well, Nick, I, I can't think of a better place to, to call it than there, and I, I really appreciate you being with us today for sharing these cases, both the victories and, and the, the trials and tribulations. And, and, um, uh, I really appreciate you, uh, joining me today on the AHF podcast

Dr. Nicholas H. Mast 54:04

Yeah. Uh, again, it's, it's my service to the community. I, I had to go through my, my school of hard knocks, and if I can keep somebody else from having to do the same, that, that'd be great

Joseph M. Schwab 54:15

Well, thank you so much

Dr. Nicholas H. Mast 54:17

All right. Take care and thanks again

Joseph M. Schwab 54:20

Thank you for joining me for this episode of the AHF Podcast. As always, please take a moment to like and subscribe so we can keep the lights on and keep sharing great content just like this. Please also drop any topic ideas or feedback in the comments below. You can find the AHF Podcast on Apple Podcasts, Spotify, or in any of your favorite podcast apps, as well as in video form on YouTube/@anteriorhipfoundation, all one word. Episodes of the AHF Podcast come out on Fridays. I'm your host, Joe Schwab, asking you to keep those hips happy, healthy, and maybe fracture-free