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Good evening everyone. Good evening. From me to what I want to do is to establish some context for the management of bowman defects. The first element in the question of context is what we call the personality, the fracture. It's a well established concept that we use for teaching uh young surgeons. And essentially, it's a it involves consideration not only of the factual in this case, the defect but the limb containing the defect, the patient in all the complexity that that might involve and as well the capacity team that is looking after the patient, not only clinical skills and experience, but in the context of uh capacity and equipment available to it. As an example of this context, here are two tibias with equivalent defects, but they are completely different. On the left is a surgical defect. We have removed a segment of tibia, the soft tissues are intact, it's planned clean. Hopefully there has been no neurovascular injury and the fibula is intact by intentions on the right. There is a similar defect or similar size defect, but it's caused by gunshot wound. There's a large contaminated soft tissue wound which will become rapidly infected there's possible or probable neurovascular injury and the fibula is intact by chance. The second issue of terms of context is the numbers involved. Um This is a, an old picture of a multi barrel rocket launcher, but the commander of this vehicle was injured because he rolled his vehicle over and his leg was crushed. Um So there was one patient, one limb, one injury, it's a very severe injury, but there was only one patient at a time. In contrast, at this hospital or 100 and 60 patient's admitted between two in the afternoon and 10 pm at night with gunshot wounds. These are four of them. This is the recovery area of that hospital at eight o'clock on the 14th of noon. Yeah, there are, this is the every area that services six operating theaters and every inch of space is filled with patient's with gunshot news. The context of the management of bone defects is obviously of critical importance. And in England, there was a great teacher of orthopedics, Alan Napoli who used to ask students, what is a fracture? The answer he was seeking was this a soft tissue injury which the bone happens to be broken and the context of war wounds. It is a supreme illustration that this is true. It's principally a soft tissue injury in which the bone happens to be broken. Our focus is the bone defect for the purpose of this talk, not the precursors but not resuscitation we're not discussing revascularization and we're not really focused on soft tissue cover. Although these are all of great importance, what we are talking about is the bone defect or the critical defect. And this has been defined as one that would not heal spontaneously despite surgical stabilization and always requires further intervention. The defect size has is usually more than want two centimeters and often larger or there's more than 50% circumferential bone loss biologically. This is different from a non union and nonunion. There's loss of the healing potential and that's often biomechanical. Whereas with the critical defect, the bone ends may well have healing potential but they're simply too far apart to enable it is to happen. The knowledge of what techniques are available are essential. So when you're initially treating uh these injuries, you know what might be needed in the future. The methods include bone grafting and papi know techniques induced membrane techniques, distraction history of genesis such as acute shortening and lengthening bone transport or combination of these. Um There's been a recent systematic review and meta analysis of the management diagnosis or bone defects published only in February 2020 which looked at a number of papers which dealt with the use of um bone grafting and membrane techniques as well as bone transport and on occasions free fibula graphs. Now we're on two specific techniques. A bit one, posterolateral grafting for infected tibial nonunion or defect is relatively rare. So rare. That we can't find any of our own examples. But it is a useful technique, it's used in many parts of the world. And this is a very good review of its effectiveness. It's quite an old review, but it comes from the Shock Trauma Hospital in Baltimore. The objective of this method is to achieve a tibiofibular synostosis iss and simply bypass the defect. It is very useful when the anterior tissues are in poor condition. Uh There's been a talk and publication recently about induced membrane techniques which have acquired the name masculine as though it was a new technique. It's in two stages. The first stages, debridement stabilization with a single cement spacer with or without antibiotics. The second stage at 6 to 8 weeks, his removal of basa with the preservation of the membrane and bone grafting in a slightly different way. This technique has been in use for certainly 30 and probably 40 years. The slide, the X ray on the right shows cement beads rather than one block, a system of antibiotic, impregnated cement beads. We did not know in those days about osteogenic membranes, but we did know that if the second stage of this procedure was delayed much beyond six weeks, it was almost impossible to remove the beads because they were embedded in new bone. This is the uh the case uh from which that X ray was taken an open fracture of the mid shaft of the uh tibia with I see the tibia moves from being left to being right, but it's still the same tibia. Uh And this is the first attempted stabilization. I'm sure everyone will recognize that a uh an external fixator pin placed like that will almost certainly have devitalized this fragment. Uh At the second debridement, the dead and devitalized bone was removed and the space was filled with these antibiotic, impregnated beads. And their purpose was principally, we thought to sterilize the cavity and to provide a space for the bone graft later to go into at six weeks and preferably not later, the bees were removed. The bone graft was inserted in this case, the external fixation was changed and it went on to uneventful union. There is one small technical point, you will see that the external fixator pins initially put on a straight, but these ones are bent. That was a technique which was common in those days for pre loading, the pins which reduced uh insight infection and loosening rates. This external fixator would be in place for many months. And with preloaded pins, it was not necessary to alter it. Bone defects depending on the initial management may often be associated with shortening and deformity. And the uh mascular techniques may not be able to deal with. Obviously, management will depend on the soft tissues which will often be affected, possibly impaired circulation and nerve function, but predominantly it's infection that will cause the main problems and it's certainly been shown with mascula techniques that you have a higher incidence of failure if this residual infection. So we have um we have therefore relied on distraction history, genesis as you are aware. Um This is the law attention stress described by it is off that gradual traction on living tissue creates stresses which stimulate and maintain active growth. This this this this is um the x rays of the patient's you saw previously and this is a gunshot wound with an intact fibula. This lends itself because of the intact fibula to bone transport. And we have found this a reliable method. Um probably more so than masculine in these injuries on the light. You can see the formation of the bone and um the healing of the fraction. The difficulty with these techniques, whether it's been in transport or acute shortening and lengthening is that the frames are on a long time and you need a big team to be able to look after these patient's uh the photo at the bottom shows part of the team. Now we come back to uh friend who's leg was crushed by the vehicle with driving. And we're discussing these different methods used in combination. This is a long defect uh would be take a long time for anyone method to fill that. So the first step could be shortening and of course, that's well demonstrated because the long lines of beads are now much shorter, shortening allows us a greater opportunity to deal with the soft tissue injury as well as accelerating the overall healing process. In this case, shortening by five or six centimeters enable the wound to close and the beads or whatever sterilized the cavity, we then change. This is the second change of external fixator to a circular frame. Uh We take the beads out bone graft the bottom distract approximately and we end up with a five segment tibia. The first segment is normal bone. The second segment is distracted is consolidated, distracted callus. The third section is more normal bone. The fourth section is more uh is consolidated bone graft and the fifth section is uh more normal bones. Uh The Lazzaro method does not always require the circular frames. The apparatus. This is a case of a multi fragmentary femoral fracture which was treated with an introductory nail which was dine um ized by removing the proximal uh screws and the tip of the nail appeared in the buttock. There was a lot of shortening. This is the method but is definitely not the lasar of apparatus. This is a simple lengthening over an intramedullary nail to restore femoral length. And the advantage of course is that when the fema is out to length that can be locked distantly and the external fixator can be removed while the bone consolidates the alternative methods of shortening until the bone has united has definite advantages. And there are more recent methods of using lengthening nails to restore bone length, particularly in the femur, although sometimes in the trivia. So some chats company hips binary treatment will influence the later reconstruction and therefore it needs to be planned for. Secondly, the defect in itself is rarely an emergency. What is important is the debride mint and the initial stabilization and planning for the future flaps usually proc you'd acute shortening. We have found it very difficult to acutely shorten um tibias, especially and femurs if they have a free flap or even the local flat um in place. And we've been doing more bone transport since we've had to work with plastic. Certain's, but what is important is sterilizing the va cavity sterilizing the defect. So initial debride mint plus or minors, uh vacuum phone dressing, antibiotics. Certainly, when you come to the reconstruction, taking multiple specimens in a specific way so that you can check on what is being grown. And then we use stimulant, which is calcium sulfate, antibiotic loaded um uh plan annuals um to fill the gap. One of the reasons we use it and why it's quite good in transporting is that you can put it in the gap. And by the time you want to transport, um it would have absorbed um the source of the graph. Um really depends on how much you need. Anterior islet quest, posterior iron. That quest where you can easily fill a 5 to 6 centimeter defect, possibly other places. And then we're we Irrigator aspirated. Er, and we occasionally also um combine the bone graph that we take with D B X or bone bands. Could I emphasise what Sarah has said about the uh about the primary treatment influencing reconstruction? I think we saw two weeks ago, a young man who was four years from injury, had his first treatment, had his early treatment been appropriate, he would have probably been restored as best as possible within 18 months. But at four years because inappropriate primary treatment, he was facing the possibility of amputation. Each of these uh, tips are topics themselves were now coming to an end. This is the last of our tips and this is, uh, probably something that is well known to you, but the use of ketamine for dressing changes. This is a young soldier who's blown up and he's lost both legs. He has a pelvic fracture, his genitalia have gone and he's left arm has an open fracture. One week after this dreadful injury, he is having his dressings changed. It happens to be in a burns bath but it could be anywhere he is awake. He is holding the shower hose with which his dressings are moistened so they can be changed.