Pam Luke (3:50)

Just quickly, when you look at your algorithm and I've read, read some of your articles, there's lots of different ways to treat things. And so some of the things I'm very interested in. If you're trying to take someone's hind foot out of varus, what is your go to Cotomy?

Glenn Pfeffer (4:06)

Great question.

Pam Luke (4:06)

And then number two, quickly, is the incision. So I always struggle because if I'm cutting the calcaneus, I'm dealing with the perineals. Even in my. In like athlete cases, I always have this struggle. One incision, two incisions. I saw in many of your articles you have one large incision laterally. And maybe just speak to your tips and tricks on that, how you expose both.

Glenn Pfeffer (4:29)

Okay, so. So very specifically, I'm really, you know, interested in, you know, surface mesh analysis and statistical shape modeling and deep learning algorithms. I'm never going to get to it, but we were actually working with an aerospace engineer at usc, and a group of us went down to Nvidia and as I mentioned earlier, and it's going to happen, but it's difficult. And the real way that's going to help is how to do your osteotomies. The human brain could not understand the calcaneal deformity sufficiently. It's a multiplanar deformity. The radius of curvature in some calcane eyes. 2000, 3000. It's basically straight in normal people. Here it's 400. If you look down at the foot, the axial coronal is. It's a C shaped calcaneus. So in terms of the incisions and I'll just get to the calcaneus in a second. Plan them all out, draw them all out. You don't want to get stuck two. I've tried both incisions, Joe. Laterally, I use one incision and it goes right over where my osteotomy is going to be, over the calcaneus and just loops around right to the base of the calcaneus and extends out to the base of the fifth metatarsal. This type of extensile incision, a lot of us have been burned by. Because we're used to it from calcaneal fractures. Right. And that's why we do this more lateral approach or mis approach. Calcaneal fractures, it ain't a problem in these people. These are not smokers, they're healthy people. I've never had a problem with that incision. Well, that's not in revisions. It's a real problem because you have to deal with the incisions you've been dealt. And maybe I've had one or two or three problems over the years with that incision at the tip. Where I've had a. Most of my patients are from out of state and I've told them after two weeks you have to stay an extra week. I'm sorry, but it's really rare. Just watch out for the sural nerve. Keep that flap deep and it's just a no brainer. And then you'll see your calcaneus. And the key is to realize what you can do to correct the calcaneus. You have to correct the weight bearing lateral to the midline and do with what you have to. A lateralizing calcaneal osteotomy does not work in most of these patients. They have this short, small radius of curvature, big curve. Right. A big C shape. The Dwyer, if you had a pick, is probably the best one to do. But even that's not enough. So it's not uncommon that we'll do a Dwyer of maybe 4 millimeters, maybe 5, and shift the calcaneus laterally and rotate the heel. So I guess you'd call it what internal rotation. But to move what you're doing is you're rotating the heel, so that the tuberosity is moving laterally. So you do what you ever have to do and you're going to have to release soft tissue. So almost all these patients, especially those that need a big osteotomy, get the plantar fascia divided through the lateral incision with a styler stripping. You can't move the calcaneus otherwise. That's why when people say, oh, we're doing MIS for big corrections of the heel. Yeah, you gotta have to show me that one because I have to take off all those attachments on the heel in order to move it sufficiently. And it can be tough, but it's really gratifying when you do that. But what's interesting. Well, what I said is you can't fathom it. It's a, the brain can't understand what that anatomy is. This is abnormal morphology. But one day, you know, a deep learning of a, you know, computer program will. And then the thing for everyone to remember, which you know intuitively as correct the heel and as you desupinate the foot. Stupid word, I guess, right? But as you correct this deformity, it all sort of corrects around the second metatarsal, so the first ray goes down even further, right? You end up with more valgus of the forefoot. So you can't decide what to do with the forefoot until you've done the heel correction. This is all, you know. I'm not a big football fan, but you know what an audible is in football when they call the plan, right? This CMT surgery is a giant audible. You really plan it out beforehand. The weight bearing cts tell you nothing about the abnormal bone morphology. It has to be corrected, right? They really don't. Because even if you do a weight bearing CT with a Coleman block in place, the posterior tibial tendon is still often such a deforming force, you don't have any idea what's going to happen until the soft tissues are released. So some brains hate this. My brain loves it, trying to figure this out as you go, right? And the forefoot's easier just to conclude because what I'm trying to do is to bring the first ray up to the second and that's all. And you just take out what you have to. In an adult, I always do a closing wedge osteotomy. It's simple, was Roger Mann's technique with a screw and a wire. And for kids, do an opening wedge cuneiform osteotomy. It's a beautiful operation. It's not that hard. We're not used to it. You do it through the medial approach. You just extend it a little further. And I use a fresh frozen allograph. Fashion by hand. I suppose you could use anything you want. What's available. It just sticks in there. You don't have to use fixation. And what's nice about that is there's often a little adduction deformity, especially with cmt. So the opening wedge actually will abduct the first ray a bit. So it's really lovely. And if you're going to do that with people, you only need it though. And someone whose physis is open, that's something. What do you think in the 12 year old or younger population you have to do? And many of us won't be doing that. Did I answer your question?

Pam Luke (10:03)

Yeah, you did. That's great. Thank you. You know, I obviously haven't done as many CMTs as you have, so I'm always just terrified about, you know, making sure my lateral incisions have enough of a bridge between them.

Glenn Pfeffer (10:15)

And I think it's okay. I think it's okay. We just, you know, we just did a surgery. It was a revision surgery and the kay had had three surgeries already. He's 19 and nobody just did enough. You know, they were doing a little bit of this and a little bit of that. You know, you got to cook a meal fully. Well, usually, you know, you can do it instead. But we had to use old incisions and it's. I hope he does well. But you know, there's probably only 2 cm between the incisions. But there's no reason not to use a long lateral exposure like that. You take the peroneals out often you have to decompress the trochlear process. You know, the tunnel they're going through on the lateral board of the foot. I always do a pull over Taft weave. I really would discourage people from doing side to side weaves. It's quick if you want to do seven cases a day. The pullover Taft weave with three throws may take an extra five minutes, but you can really tighten it up there. You can't tighten as well. A side to side transfer. Greg Guyton's always saying he does the transfer in the distal third of the leg. And I'm not against that, but I'm right there with that incision. Divide the peroneus longus distally, take out the little osp perineum that's in there. That often gives too much bulk and just often you have to thin out the peroneus longus and then you can just weave it into the bre. If you're doing an FHL transfer, you know, we pick it up in the distal third of the leg laterally. The perineals are usually very badly scarred down. And I'll like, because I haven't been working, which is why you need to go to the fhl. And then I'll just thread it into the perineal tunnel, but I'll take out the peroneus longus, I'll divide it in the leg, I'll divide it distally. I want some room to pass that FHL transfer. Why pass three tendons down the tunnel?

Pam Luke (12:00)

I think I've struggled. One of the things maybe you could tell me like I struggled like, let's say even in other cases, like an athlete is gauging the length of the perus longus or brevis. You know, like sometimes there's a split tear and you say to yourself, okay, I'm going to repair this, maybe tubularize it. But you know, for cmt, I've, I've always tried to do a more like you said, a longest to brevis transfer where I can tension it. And I've read you like to tension it in maximal eversion or I am for 10 degrees, I guess that's pretty maximal. Can you speak to that a little bit? How do you gauge if you've gotten it tight enough on the lateral side?

Glenn Pfeffer (12:37)

Well, in terms of length. Well, you mentioned length, I thought. But in terms of the fhl, if you harvest it in the foot in the midfoot, you always have enough length, you know, you're always cutting it off. In terms of the peroneus longus, you know, if you cut it distally, right where it goes from vertical to horizontal, you'll have plenty of length to do three throws. In terms of the tensioning, it's a very interesting question and that's driven me crazy too and made me feel very stupid, which these things that made me feel stupid in my life. This is revenge, baby. Because you sit there and you listen to a very pedantic lecturer who knows the answer to everything. And I'm thinking, really, I'm so stupid. But first of all, Joe, most of us in foot who do adult are used to doing transfers of an fhl, like for Achilles, right? If you said, what's the most common transfer you do to foot society members? I bet you they would say we don't do it much, but forgetting girdlestone at the toes. But we do the FHL transfer into the Achilles, right. And what you do for a chronic rupture and there what you do, right, you tighten it as much as you can. That's what people will say. But you're limited by the muscle belly being so distal. So we're inadvertently tightening it the right amount because you can't pull it too tight. Right. People say the posterior tibial tendon transfer should be tightened to the maximal amount. You know, if you go through the interosseous membrane and you go into the cuneiform or whatever, I don't think that's the right thing. You know, probably 75% of excursion, 80% of excursion is what you want. It's sort of a blitz curve issue. You know where the muscle's going to function best. But 75% is good. I want some plantar flexion play, especially if you've lengthened the Achilles. You certainly don't want to over tighten that transfer for the lateral transfer. Because I see a lot of these patients for their other foot and they come back five months later or four months later or two years later. And the peroneal transfer, no matter how tight I do it in cmt, doesn't ever seem to be quite tight enough. They seem to stretch that out even if I've gotten a terrific repair so that they're invest some slight valgus. So I'll, as I said, just, I think of it as a sub tailor fusion. I'll take the peroneus longus. And these people don't have plano valgus feet, right? These are not normal feet. So you've just managed to get the heel over with your osteotomy. And I'll really tighten it quite snugly. It's not common, but occasionally I'll just say, gee, we have to redo this. It's just not snug enough. I don't need any excursion there. But you know, I'm surprised that more of them don't get a plano valgus complication. You've taken everything away. You've taken away their ligaments laterally, although not the subterior ligaments. You've taken away the posterior tibial tendon. Remember that the FHL and the FDL can be deforming forces. So you're taking the posterior tibial tendon. Take a look at that, those other tendons. You know, I'd like to keep their functions. Not commonly, but just last week I lengthened the fhl, you know, so they don't have much medially anymore. Anyway. That's what I do.

Pam Luke (15:47)

Do you ever worry that if you make it too tight. Because I always think about this. If you make the perineal. Now I'm only making one tendon. Right. Transferring long streps. Do you ever worry it's so tight that it will subluxate over the fibula?

Glenn Pfeffer (15:59)

So in again. These are CMT patients I'm talking about.

Pam Luke (16:03)

Yes. Yeah.

Glenn Pfeffer (16:03)

That happened to me once. Only once. Ah. But there's a key to that. You mustn't dissect them out above the tip of the fibula. If you do, you have to repair that peroneal sheath. Don't go above the tip of the fibula. I've had one patient from Oklahoma who did. She dislocated her tendons. It's the only patient. And she had it revised in Oklahoma. It didn't work, unfortunately. So she came back for her third operation. And the only thing I could think of doing, which has been published, is we actually just divided the tendon distally and put it underneath the calcaneofibular ligament. Right. It's published. And. And she did beautifully with that. And they don't look anymore, but that's like rare as hen's teeth. But Joe and CMT patients, I just don't worry. I mean, you say you put them in 10 degrees, you're thinking of maybe the athlete or you're thinking of someone who has a plano valgus. Right. You couldn't put these people in 10 degrees if you wanted to.

Pam Luke (17:01)

Oh, no, absolutely not. You're correct. Of course. Yeah. I just. I'm just saying when you talk about length, I just mean knowing the tension. You know, if you have somebody who has a perineal injury, tendon injury, there's always this thought in my brain of even if I do a perfect repair, are they going to have enough power to evert. You know.

Glenn Pfeffer (17:17)

Right. You know the guy who ruptured the tennis player from Palm Springs recently, and he had nothing left. He'd ruptured his. He just ruptured his tendon, though. The. And I. I forget which it was. There was one tendon that was. One was chronically ruptured and the other one had just ruptured. But whatever it was, we put an allograft in and I was able to sew it into a stump distally. But there. Absolutely. I just kept the foot in neutral position and I put it to 75% tension.

Joe Park (17:45)

So for the consensus statement that you wrote on CMT, I think it's. It was published in 2020 in FAI and I guess I would be thinking in the last five years, you know, are there any other bullet points or things that you've seen that you've learned in your patient practice that you would add in addition to that consensus statement that we should be aware of? Because the consensus statement had. Excellent point.

Glenn Pfeffer (18:06)

It's a terrific question. But it's on the assumption that I remember what we said, and it's also working on the assumption that it was consensus. Do you know what I mean?

Joe Park (18:14)

Right, right.

Glenn Pfeffer (18:16)

I wrote that, and I'm not sure that even other authors even know it. I don't want to get into trouble, but I actually put a few sentences in about what I do, even though they all disagreed with it. And, you know, things like possibly or could. I think the main thing, I haven't looked at it for a while, but I do remember a couple things. One is I would release all soft tissues. I think in our, you know, what was the order of what surgery to do? For some reason, we. We did the calcaneus osteotomy before doing the peroneus longus division. Just release all your soft tissues. Everything that's going to be released. Release. Right. Release your plantar fascia. Release everything. And I think the big one was the Achilles. There was a real discussion about that. And almost everyone in the room thought that the Achilles, the Achilles is not active. It's not causing equinus. And because of the position of the talus in these patients, they really can't dorsiflex that much. The talus, just the opposite of a flat foot, where the talus is inclined downward. But these talus are horizontal. They're almost parallel to the floor. There's no room to dorsiflex, but it's the deforming force of the Achilles, of an inversion, that it's the key. And I think that's a big change. What's happened in my practice is. Well, it's wonderful. It's just a very, very rewarding career for me because I've gotten to do what I love the most. But it's not cookbook. Right. This is not a cookbook issue. And if you're going to go to the neurologist at your institution and say, I want to do this, you sort of need to be able to deliver on it, and you have to be able to work with that. 25, 35% of patients who are not cookbook, the CMT1A, I think, tend to be a little more cookbook in the way that they are. Right. The classic Deformity that we all know. The axonals, the twos, they're very unusual in how they can present. They're very unusual. And they may not have tibialis anterior weakness. Their toe extensors often work well. Their post tib may not be a major deforming force. It's a very different disease. I mean, what are there now, 150 genotypes of CMT, right? So I think be cautious. Make sure you're really seeing what you think you see in your exam. You know, there are all these aphorisms about what did I forget? They're not, you know, the prepared mind can see things. I don't remember them. But, you know, if you don't know what to look for, you're not going to see it. And if you see someone who has a CMT non 1A, be very cautious. And everyone in the room, for example, in the consensus statement, they said perennial is longest. What's the big deal? You just measure the strength, okay? Do that study with your residents, do it with your fellow attendees and have people measure the peroneus longus and see how reproducible that is. You know, and it's a key issue because if your peroneus longus isn't strong, your whole operative approach is going to be different, you know, and you're going to fail if it's not strong. So I think what I've learned in the past five years, not remembering exactly what's in that, is almost always the Achilles, almost always with a poke, triple cut. And you know what's beautiful? You can't really over lengthen it. Not really is the tailless doesn't go up enough to over lengthen it. I tell people to be careful, but you couldn't do it if you wanted to. And you'll see that healing just come right out of varus. I've learned to really respect the axonals, you know, the type twos. I've learned to be completely humbled by kids prepubescent. Just to show you, though, Vince Moskva was chairman at Children's Hospital. Vince said he did about 500 CMT cases before he retired, and which at one time that was just an overwhelming number for me, you know, here he is at Children's Hospital in Seattle, wrote the book on foot and ankle. How many posterior tibial tendon transfers do you think he said he did in his career under the age of 18? I don't want to misquote you, Vince. I'm sorry if I am, but he said I Can't really remember if I've done any. He said, yeah, I guess I have, but that's pretty rare. You see the difference. And we had discussions. He goes, well, maybe we have a different population up here. But that's what really gave me the strength to realize the posterior tibial tendon doesn't always have to be transferred. That dumb guy in the audience who was me all of a sudden said, wow, you know, maybe I am onto something here. And watch the toe extensors. They really compensate and masquerade and you'll get it wrong and think of transferring the toe extensors. It's a beautiful operation. It's in phase. Two weeks after surgery, you take out the sutures and you say, try to move your foot. I think those are the main things. I didn't really take notes what to talk about, but I think those are the main issues.

Joe Park (23:35)

That was so helpful.

Glenn Pfeffer (23:37)

Oh, one last thing. Sorry. We're actually going to study this now. Where do you release the plantar fascia? It's really interesting topic. The pediatric orthopedic surgeons, many of them say you have to release the plantar fascia first. And they release the abductor and they do some other soft tissue, maybe something. And then they put the patients in a splendor cast, and they don't do anything to the Achilles. And they say, you can't do anything to the Achilles. And they start pushing up, you know, to get the foot and the plantar fascia stretched out because they've divided it.

Pam Luke (24:08)

Right.

Glenn Pfeffer (24:09)

That's an interesting issue to me. We're just going to start studying that. How much? If you divide the plantar fascia under the calcaneus, how much does it really translate distally? Wonder how much it really does at all, actually, you know. And what's really happening there? Well, if we're going to release the plantar fascia, we always do it in the midfoot right there. And instantly it just stretches out and lets the first ray come up, you know, and it's not uncommon at all for us to do a double plantar fascia release, but for different reasons, and no one in the consensus statement done that or heard of it. But we release it beneath the heel to let the tuberosity move. Right. And I release it in the midfoot so I can correct the deformity of the forefoot and bring the first ray up. And I was writing a paper about six months ago, and I had missed this. I was very gratified to see that Nathaniel Gould, John Gould's Father Nathaniel was one of the founders of the Foot Society, published this, and he said you always have to do it. So, you know, it's all out there. Everything about CMT is out there. I don't think there's anything new under the sun. You just have to read it all and put it together. And the nice part about it, it's not like total ankles where there's 20,000 articles. They're probably clinical articles that mean anything, 25 articles, total chapters. So you can really get a handle on it if you want to.

Pam Luke (25:39)

Great. Well, Glenn, thank you so much for your time. I really quickly, before we close, I just want to tell you there's a huge population of CMT patients near Charlottesville, about an hour from here in this area called Harrisonburg. And, you know, I don't know if you've ever seen patients from there, but it's interesting, these populations that have been in the same location any, any generations, and if the gene pool is not, you know, super broad, how these little enclaves can take place. And it's been very rewarding to try to help these patients. I'd hope someday I can do it even half as well as you can, but it's been great.

Glenn Pfeffer (26:12)

You'll be able to do it fine. It's just a question of what to do and when. And the issue of doing when, I guess we didn't touch on that. But when somebody can't walk in a brace comfortably, that's the time to do the surgery. And I don't care if they're 7 years old or I don't care if they're 50, 60 years old or 70 years old. I've operated a 74 year old. But don't let a crooked foot in a brace. You can't put a crooked foot and straighten it out, you know, in a brace. And sometimes you meet young people just don't want to wear braces. And if they've got the muscle strength available, that's reasonable to not want to wear braces your whole life. I'd be glad to come out with you, Joe, if you're really interested one day invite me to give some lecture on this or see if I can come out and we can. Maybe they can give me some we can privileges just to examine some kids or go to the surgery or. I'd love to see that part of the world.

Pam Luke (27:06)

Yeah, of course. I'd love to have you here. Amazing.

Joe Park (27:09)

Amazing. Thank you. And hopefully you guys can join us again for another series on our Aophas Ortho podcast. Thanks guys.

Pam Luke (27:17)

Thank you. Thanks Glenn. Appreciate it.

Glenn Pfeffer (27:19)

Thank you so much.

Podcast Host (27:21)

Thank you for listening to the AOFAS Ortho Podcast, a Convey Med production. To learn more about joining our dynamic community of highly skilled orthopedic specialists, visit aofas.org.