• LecturehallPediatric/Adolescent Flatfoot Correction by Osteotomy and Grafting
  • Lecture Transcript
  • All right, for the brave few that are sticking it out, we've got a couple of good topics I think, before the conclusion of our total program. And the one I'm going to share with you now is, pediatric adolescent flatfoot correction by osteotomy and grafting. And in 41 years of doing surgery for reconstruction of significant, what I call uncontrollable hypermobile flatfoot, I've had the opportunity to use various approaches. I would tell you as a general comment, if I can use arthroereisis, usually in conjunction with TAL or gastroc lengthening, that is a preferred treatment of choice, and one of which you can do in a much younger age population – 3, 4, 5, 6 years of age, which has dramatic influence on the function of the foot, dramatic repositioning of the peritalar subluxation, eliminate the deforming force, control the position of the foot, and allow the foot to adapt. You need to think in terms of pediatric flatfoot as one that is growing – one that can undergo functional adaptation and change. When we deal with the adult flatfoot, we have a whole different problem to deal with.
    So the pediatric is a golden age of opportunity, if you will. And if I can avoid osseous procedures, I would prefer doing that. Unfortunately, we do see advanced deformity that will not respond to single arthroereisis type of procedures. And that's what we're going to focus on here.
    So my indications for surgical intervention is, uncontrollable hypermobile flatfoot. And in the other day, when I talked on the conservative management, utilizing a very controlling orthotic, that helps me determine that it's uncontrollable. All right? We'll also talk after this on the pediatric flatfoot, on adult flatfoot, PTTD Stage 3, which obviously requires surgical intervention as well.
    You usually see a fair amount of supinatus in the more severe, flexible flat feet, even in some of the rigid ones, and equinus. And we need to identify each one of those problems. Generally speaking, what are we trying to accomplish? Relocate the mid-tarsal subluxation. Rotate the midfoot at the ball and socket talonavicular joint. Increase tension on the peroneus longus, and derotate the longitudinal axis of the mid-tarsal joint. This is where supinatus is reduced by the action of the peroneus longus. And the repositioning of the peritalar subluxation is critical to help stabilize the lateral column of the foot so the peroneus longus can have dramatic influence on the medial column of the foot, which includes first ray and long axis of the mid-tarsal joint.
    So we want to decrease forefoot supinatus, lengthen the lateral column, and increase height of the longitudinal arch. And when we talk about lengthening the lateral column, we're obviously talking about an Evans flatfoot correction.
    So again the pre-operative criteria – uncontrollable, painful, equinus is present. We often see a transverse plane domination in this foot type; forefoot supinatus; no evidence of DJD, and in youngsters you're not going to see degenerative joint disease. Ideal ages are 8 to 14 and we want to deal with this talar escape. So when we look at this foot type, we see a significant amount of either eversion and abduction, and you're going to need to take X-rays of leg and foot to determine if in fact the calcaneus is everted or it's abducted. There's going to be a differentiation of my selection of surgical procedures of a lateral column lengthening versus a transpositional osteotomy.
    So we do look at X-rays, obviously, to determine areas of breakdown, planal dominance of deformity. The other day I mentioned that a calcaneal inclination angle that is of relatively normal position and height, and a pretty good Syme aligned with significant supinatus, identifies for me transverse plane dominant deformity. These are often internal torques. Youngsters who have, are toeing in severe pronatus, internal torque is one of the most severe deforming forces in addition to equinus controlling uncontrollable hypermobile flatfoot. And it's interesting that literature will talk about the fact that youngsters who toe in usually outgrow it by the age of adolescence, but they're left with the flat foot. That is what we have to deal with. So even when I'm dealing with youngsters who toe in significantly, there are times I will recommend surgical intervention or controlling of the flattening of the foot while they outgrow or while I'm even treating the internal torques.
    On a dorsal plantar view, I do look at tallowed calcaneal divergence and cuboid abduction. And Guido sitting here in the back of the room, identified in an article many years ago, cuboid abduction – the relationship of what's going on at the mid-tarsal joint which becomes transverse plane dominant. So if I were to just isolate this X-ray, my goal would try to be to rotate this foot back around the talar head. That's the peritalar subluxation. And Evans talks about doing that by an osteotomy of the calcaneus, about 1cm proximal to the CC joint, which causes an elongation of the lateral column, and in so doing, you're going to spin the forefoot around the head of the navicular, of the talus.
    Now, it's interesting, whether you're going to do a wedge type of ostetomy or just put an interpositional graft, so it's like, are you trying to wedge it over or just elongate the lateral column? Now, what happens as a result of elongating the lateral column is you increase tension on the peroneus longus, which obviously traverses the foot and has major influence on the entire medial column as well. So what I do look at on this X-ray is the divergence, the talar escape, the cuboid abduction. Do I see diastasis of the first ray? - because that is going to be part of what I'm going to see developing or leading to HAV. And of course the abduction of the foot.
    So Evans calcaneal osteotomy is a strong procedure. It's relatively easy to perform. The principle and concept is increased tension on a tendon. So length-tension ratio of tendons becomes important when one looks at the potential of doing an Evans calcaneal osteotomy. More times, an item accompanying this with either a tendon Achilles lengthening or a gastroc lengthening.
    I've heard many people from the platform talk about a cotton procedure being done simultaneous to an Evans or a Coots, a TAL, to plantar-flex the medial column. Osteotomy of the medial cuneiform dropping down the first ray. I'm an advocate of waiting to allow for the normal anatomy to recreate and reposition forefoot abnormality. So forefoot supinatus, in time, will reduce. If you've eliminated your deforming force, reposition the foot, and allow the peroneus longus to have its functional benefit on the medial column. You will then see a reduction of forefoot supinatus.
    So the location of this osteotomy is 1 to 1.5cm proximal to the CC joint. You can do it at the CC joint as an extension arthrodesis. Now, I wouldn't do that in a youngster, but I would do that in an adult.
    The selection of graft. Through the years I've used many different types of graft in the calcaneus, recognizing that the calcaneus is a big sponge. And where you're going to make this cut is going to be in cancellous bone, and now what we need is a strut of bone that is going to go into this site and hold the distal calcaneus approximately 10mm away from the proximal calcaneus. So what do you use? You can go to the bone bank, obviously, get cortical cancellous so that there's a component of strength or a scaffold. You can use femoral head, which is one of my favorites, by the way, because of the large cancellous component with a little thin cortical margin. It's a very strong piece of bone. You can also use interpositional graft from the calcaneus, which is my least of these three that I would do. Then orthobiologics. Interestingly, Cancello-Pure was something that was placed into our hands a number of years ago, which is pretty much out of favor right now. This came from cattle – very young cattle. And now biofoam, which is the thing that I use pretty much universally now, which is actually a titanium piece that goes into the calcaneus. So incisional planning is going to be predicated on what you're going to be doing. If I'm doing an isolated Evans, then I can use either an incision that goes parallel to the lateral aspect of the foot, or you can make one that goes vertical. Now, some of this planning is based upon what you're going to do to fix, if you're going to fix the graft in place in the calcaneus. And I'll show you a couple of reasons why we might have to do something like that.
    So your dissection is kind of simple, and I usually am going right towards the sinus tarsi and coming back a little proximal for this dissection. You do not violate the extensor digitorum brevis. You do not violate the CC joint – don't even open it. Identify the sinus tarsi, identify your CC joint, you can use a little 27 gauge needle to do it. You could do it with fluoroscope in the OR, c-arm. Your osteotomy is vertical to the calcaneus. Now you will find that this is a very tight environment. To open up the calcaneus is not going to be so simple. And part of the reason is the peroneus brevis, which has adaptively shortened, is applying a significant force holding the forefoot abducted. All right? So I've used various different types of instrumentation – this is a navicular clamp, so here's my cut; I put two little drill holes down into the body of the calcaneus, and I actually separate the calcaneus, because the problem you have is getting a graft in there large enough. And usually I take smooth laminar spreaders, put it into the osteotomy site, and gradually open it up and don't jump to putting a graft in. Let the soft tissues release somewhat. Not only is the peroneus brevis a resistor, but your plantar ligaments, the calcaneal cuboid ligaments, long and short plantar, as well as the fascia, can try to resist you from moving that foot over.
    All right, here's the interpositional graft. Here we are open, the clamp is out of the way, you can use a xxxx [12:53] clamp – there's various different ones that you can use – open the osteotomy, evaluate the size of the graft you're going to use, and then I either cut it to shape or I'll show you the biofoam that I use instead of having to go through all of this type of wedging. Now, certain companies have product already wedged for you, different types of bone graft, to go into the calcaneus. And here is the portion of bone in.
    One of the things that I have found is that the distal aspect of the calcaneus actually becomes rather unstable. As careful as you are in your dissection, you will see displacement of the distal aspect unless you protect against it. And I'll show you how we do that. But here's an example of what you're accomplishing with the Evans procedure, so I've reduced the cuboid abduction, I've covered the talar head, and now I've repositioned the foot, so I do not see that severe hyperpronation syndrome.
    A word of caution: do not overcorrect these deformities. You're not trying to have this talonavicular joint wholly articular. A little bit of prominence is good because pronation is a normal function of the foot. We don't want to created a supinated foot.
    And here's an example on the lateral view of change in position. Look at the forefoot. There's your supinatus completely reduced, but here's the graft in place, and you can see the distal calcaneus and the graft have come up.
    So we either violated the CC joint or when we put this graft in it just took the distal calcaneus right up. It's actually not bad. We got an arthroereisis as well as doing an Evans on this patient. But that is not the ideal. It's not what you want to do. So I've done some things to try to avoid this from happening, and I'll show you what they are. One of them is a pin. Before I even make the calcaneal osteotomy I will take a Steinmann pin or a Kirschner wire, six two, and place it from the lateral aspect of the foot through the cuboid and into the more distal aspect of the calcaneus. And then I need a c-arm to show me where it is. Then I make my cut in the calcaneus. By doing so, there will be no displacement of the distal portion, and by doing so, once I put my graft in, I then can either extend the pin to incorporate the graft, and the proximal calcaneus.
    And then of course casting orthotics. Now here's some other pictures of it. Here's another type of retracted – it really opens up the calcaneus beautifully, and almost wedges as it does it. Peroneal tendons need to be protected. They sit right underneath, and the peroneus brevis and longus are going to become very tight. You can determine on the field the size of the graft that you're going to need and the reduction of supinatus right on the operative field by looking at how much you're opening and what's happening to the medial side of the foot.
    Now, here's a device that works very well. It's a beautiful technique, because there's actually a lollipop, a little template that you could put right into the site, and there's different widths of this in millimeters to determine just how much I need to correct this foot type.
    And there's the graft in place. This is titanium. There's actually a hole in the middle of this graft that you could put a screw or a wire through. Care, again, to be sure that the integrity of the distal calcaneus is maintained, and you could see on this foot how this arch has dramatically developed right on the operating table by doing it.
    Now here's an example of a double osteotomy where I used a Koutsogiannis, as well as an Evans procedure.
    Now, another approach to take when you're putting grafts in the calcaneus is putting a plate over it, so that you will get no migration of the distal calcaneus and/or graft. The only problem is, you do not have a lot of soft tissue in that area of the foot. So the graft can be very problematic. But here's an example of a transpositional osteotomy of the calcaneus, along with the Evans, to not only deal with the lateral transposition but also the abduction of the forefoot.
    And here's this peg in place.
    And these type of patients do rather well. It's extra-articular. It's not violating the joint or not creating a fusion at the site, and if I can do extra-articular procedures, I would rather do that in the correction of my flatfoot.
    Here's another shot showing the entire instrumentation, the packing in. Here's a plate going over it. That's not my preference, I will tell you that – I said this becomes prominent, shoes irritate this area, and then youngsters, I want to be one and done with the surgery, not having to go back in. And this incorporates very well, when you look at these titanium pieces. They feel and look just like cancellous bone.
    Now you can do calcaneal cuboid distraction if you're going to do an Evans in the adult foot type that has a significant transverse plane, but some people have proposed that in the adult, if you do an Evans, there's going to be so much compression that occurs at the CC joint that you'll develop degenerative joint disease. Now the CC joint probably is the least important of the subtalar mid-tarsal complex. So if I can do an osteotomy through that joint, put a graft in, put a plate over it, now I've gotten my reposition, and do not worry about any compression at the CC joint. And that's what that looks like. And here again is a Koutsogiannis, along with the calcaneal cuboid.
    Here's some other plates that can be used. There's some other companies that have little plates that have a wedge built right into them to do a lateral osteotomy or cotton type osteotomies. They fit right over the site. Here's an example of one of those plates. I guess the advantage, I would say, to this, is that it maintains perfect alignment of the calcaneus distally and proximally. And then you can either back fill because the flange that goes in that tapered part does not go all the way across. And the calcaneus is so vascular it fills in and heals beautifully, but you can certainly back fill that with chips.
    There's an example of how much of a space you will see. To me I want to fill those spaces. I don't like leaving all that hoping everything will just fill in by itself. There's an example of what that plate looks like. Those screws, which are locking plate screws, but look how much of a void is in there. And you're hoping that that gap is going to fill. So you either use an orthobiologic or bone graft in addition. And there's the different sizes of these LC, LP plates.
    Cotton medial procedure, as I've said earlier, I don't do many of these. I think it's just a matter of time to allow for the supinatus to reduce. The more things you're doing the more problems you can run into. It's a simple dorsal planar approach. Open it up. Once again, you can use the clamps. You can also just planar flex the entire first ray, and you then put your appropriate amount of bone in.
    Koutsogiannis, powerful procedure for transposition of the calcaneus, and again these are severe flat feet, and you look at it and it looks like there's a severe Helbing sign but you actually have significant transposition of the calcaneus. It's an easy one to do. You make this lateral approach, you go right down to bone – obviously avoiding the sural nerve and the peroneal tendons. You make a cut directly through the calcaneus, and the only care you've got to be is on the medial side, your neurovascular structures are going to be palpated, and when you come through with the saw blade you do it very gently. And sometimes when the residents are doing it, I say, “Do not go all the way through. We'll complete it with a little osteotome”. I then put my laminar spreaders in top and bottom – smooth-toothed laminar spreaders – so that I can spread this osteotomy, take some of the tension off the deeper of the medial structures, and then just shift at least 8 to 10mm of the calcaneus to get your transposition.
    I don't care how you fix it – you can use plates, I've used screws, I've used pins – here's an example of some screws that are being used – very simple approach. The calcaneus heals so beautifully. If you want to use any time of orthobiologic on the defected site you certainly can. Here's nice cross-screws. Problem with some of the screws is that they're prominent, so I usually use a mock screw which is a headless screw. Asnis has a headless screw. There's a number of companies have headless screws so that they're not prominent. And obviously you're taking the position to move the calcaneus so that it is back under the leg providing the necessary support. Unfortunately your incisions can look a little large in this area. This is an example of a fair amount of swelling. But you could certainly see how the position of the foot has dramatically changed from one of transposition to being directly underneath the leg and supporting the foot itself.
    Here's another example of a severe flat foot – 11 year old. My approach on Achilles tendon lengthenings are a little different than Dr Brigido. I make two cuts. I go from anterior to posterior and posterior to anterior and dorsiflex the foot, and let the fibers just simply slide on one another.
    And here's a Koutsogiannis. I've even taken pins and done an Evans and a Kouts at the same time, and used one pin, coming right through the Evans site, and one pin going all the way back, holding the displaced calcaneus. I would say that's not my preferred approach, but I've tried a number of different things to be of benefit. And there's that forefoot approach on the cotton. If I'm doing an Evans and a Kouts, my incision planning is a little different. There we are, making the cut. Here we are, opening it with those two laminar spreaders. And you can look right down into the well, and there's your ligaments on the other side. Obviously you don't want to violate through that, but you need to stretch it out so the calcaneus can be displaced.
    And here we are using a DARCO plate, which is offset by the amount of millimeters you want. It holds everything nicely in position, and there is the ledge that you've created by shifting the calcaneus.
    Complications of any of these osteotomies, obviously non-union, I will tell you I have had a couple of non-unions on my Evans procedures. And one of the last ones I had was when I used that Cancello-Pure wedge. So since I've gone to straight titanium on those plates I've had no complication of non-union.
    Distal calcaneal displacement – that can be avoided if you're understanding what you're doing anatomically. You can get displacement of the graft and stiff rear foot by overstuffing.
    All right. I think I went over a bit.