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Hi, everyone. Thanks for coming along tonight to the third installment of her Orthopedic Subspecialty series. Tonight's talk will be delivered by Mr Gavin Brown, consultant, orthopedic surgeon, and senior clinical lecturer. And today we're going to be covering lower limb arthroplasty. So without further ado, I'll hand over to Mister Brown. Thanks Sarah. Hopefully you can all hear and see me. Ok. Um What I'm gonna do is um share some slides with you through tonight. We're gonna be using a little bit of audience interaction. Um So that's via W clap, which some you may have heard of before. Um You can access it either via your phone or I'll pop a link up on screen in a moment that you can type into your browser just to um contribute some answers to it. Um So I'll do that in a second. But first of all, thanks for having me here. Um It's always good to talk at these events. Um I'm a big fan of getting involved as early as possible with um people that are interested in orthopedics. Um It's a challenging specialty to get into, it shouldn't deter anyone. Um But you've already shown that you're, you're interested and that's good. Um So if you give me one moment, I will uh start my slides up. So hopefully you'll be able to see me um shrunk down into the corner and then you'll be able to see my slides the right way round. And so here on the screen is a QR code, if you've got your phone and you can scan that and access rec clap otherwise, um if you just type in recla.com and then we've got or Ortho, so as our joining code for that, um, so the plan for this evening, um we're gonna do a little bit of an introduction to lower limb arthroplasty, a bit about its history. Um How your training in arthroplasty might go if you get into an orthopedic training program, gonna talk a little bit about the principles of it and I'm probably gonna go quite above your head. So going into some biomechanics that we get into kind of as, as um kind of more senior grade um orthopedic registrars. But the goal of that really is to show you that actually there's quite a lot of interesting er, science that goes into arthroplasty, it's not just whack a, an implant and then forget about it. Um There's actually um a lot of biomechanics and physics and material science that go into thinking about it and then we'll finish off just with some case examples um to discuss um some relatively common things that we might see in, in, um, lower limb arthroplasty. Um, I kind of dithered about having a bit of hip arthroplasty and a bit of knee arthroplasty tonight. Um, I think just for time we'll concentrate mainly on hip arthroplasty and a lot of the principles that we talk about with hips are actually pretty transferrable to, to knee arthroplasty as well. So, hopefully you've got, um, that link to WP And what I'm gonna do is just pop up the first question for you. Um, which is just to find a little bit about who you are. Um If you could just fill this bit in here. Um I notice there's only seven people logged in at the moment. I'll give you a moment to, um, to join in and answer. Um, the aim being just to have an idea of how senior you are in terms of, of, of medical school. So I'll give you a moment to do that. Um And then we'll see. So 22 responses so far. Um I'll give it a moment for people to, to log in if you're still wanting to because we, we will be using this for the rest of uh the rest of this talk. Thanks Sarah for putting that code into um, the chat as well. It's useful. Ok. So that's good. So we've got um, a few different um uh kind of spread. So somebody getting very keen joining in year one, a couple of post grad or fy, but mostly around year and five and six. So you're either doing your, um, orthopedic rotation this year if you're in Edinburgh or, um, you, you've done it already. So that's, that's good. So I'll leave that pole open for the moment and I'll just go into, uh, start a little bit about the introductory kind of part that will lower them arthroplasty. So, first thing, first question for you after that is what are the indications of arthroplasty? Um And again, I'm gonna pop the questionnaire up for you here. Um And we'll get a bit of a word CDE for that. So you can type in as many times to suggest what some indications are for lower limb arthroplasty. I'll give you a kind of 30 seconds or so. Pain. Yeah. Um, so I you can enter things in multiple times. But um, yeah, let's have a diagnosis for, for indication for low limb arthroplasty. So, pain and limited function. Yeah, they're features of um, diseases or presentations. Um But we're kind of really looking for the actual diagnosis that would lead us to it. So, um, fracture, yes or trauma, osteoarthritis is the big one. We probably had a couple of people saying that um any other ones thinking a little bit outside the norm, normal. So osteoarthritis is going to be our most common reason to do a lower limb arthroplasty, um, inflammatory arthritis. Yeah, brilliant. So we're thinking about um, rheumatoid arthritis. We're thinking about um, uh psoriatic arthritis, things like that. Excellent. Someone's mentioned Paget's disease. So, your metabolic bone diseases. Um, yeah, you, you sometimes have them. So, other things like that. Excellent. So my, my kind of list that I've created here is really osteoarthritis at the top inflammatory arthritis less commonly, um, fracture or trauma. We often see that infection. So somebody if it gets an infected, um, uh, joint and we might end up once we've sorted the infection and the joints destroyed, we might go on to do that. Tumor also is a relatively rare, um, reason for arthroplasty, but we still do it and then other things. So, um, somebody's mentioned, um, Paget's disease that leads on to, um, osteoarthritis and there's a few other things that can cause osteoarthritis later on with that. So, really important thing as a medical student. And, you know, when you become a practicing, um, orthopod or even a, a foundation doctor is to know what you're looking for, to spot the most common, um, reason for arthroplasty. And that's gonna be osteoarthritis, as we said. So, having these four things easily rolling off your tongue, um, when you're asked by an orthopedic surgeon and what the cardinal signs of, of osteoarthritis on an X ray is really important. So, what we're looking at here is a right hip. So we've got the femoral head here, we've got the acetal just around it and the signs we're looking for is the gap between the bone and the socket. So that's gonna be um joint, space loss and osteophytes, it difficult to see on this one. There's maybe a little bit of an osteophyte just up the top here. We've got subchondral some extra um opacifications or white appearance, particularly on um the parts of the joint surface that are rubbing against one another and then subchondral cysts or periarticular cysts around here. So, as long as we've got that, we know what osteoarthritis looks like on an X ray. Other thing to say about um, arthroplasty is that it's, it's really a last resort. So we want as much as we can when we're dealing with osteoarthritis to treat it conservatively. And then once we've completely exhausted all the conservative measures that we have, which is kind of listed here, that's when we think about surgery. And so we're thinking about things like education, changing the patient's lifestyle. So, you know, if there's certain things that are causing them to get more pain to maybe cut back on those things if they can and lifestyle changes like quitting smoking, weight loss, things like that. And then introducing other um healthcare practitioners to um give them physiotherapy, maybe occupational therapy to give them walking aids, things like that. And then the, the pharmacological treatments like simple painkillers, increasing up the bladder and then adjuncts like um intraarticular steroid injections and capsaicin. There are kind of um creams that you can give people that can help with, with pain from, from knee joints in particular. So, surgery as a last resort. And if you get an osk question, always mention the conservative measures first before then going on to suggest surgery. So that's a little bit about indications. Um I thought it was worth mentioning a little bit about the history of orthopedic surgery and the history of um uh arthroplasty in particular. And this mostly relates to hip arthroplasty because that was the earliest, um, orthopedic um arthroplasty that we did going right the way back to um 1912. So kind of around about the year of the first World War. Um So Robert Jones, um, he was a pioneer of um orthopedics in the um turn of the nine sorry 20th century. Um You may have heard of him about for the Jones fracture, which is the, the fifth metatarsal. Um But he was the first person to think about, well, what can we do to try and restore some kind of a joint mind? So he tried gold foil that didn't work very well and then thought about soft tissue. Um, primarily the fascia lata used to interposition that's putting it between the joint surfaces and I had some success with that. But really, it was pretty quickly found out that that doesn't last. So then later on in the same century, we've got Smith Peterson who you may know, um, from the Smith Peterson approach to the hip and tried to do some all kinds of different things. So glass mold. So that's an example of things here is using glass um to put over the femoral head. And later on use things like Pyrex, which is a type of kind of heat treated glass and then Vitallium, which is the first kind of orthopedic metal implants that we are using. So it's like a a an alloy of cobalt chrome and molybdenum, which is what we use these days as a slightly different um alloy of cobalt chromium and then molybdenum. And then over the course of the kind of the the rest of the first half of the 20th century, we've got a bunch of old white dudes who gradually improved on each other and putting in different types of implant some of these. So the Austin Moore and the Thompson were used up until kind of the early two thousands in some ways and hemiarthroplasty that it really, really took until sir John Charnley, who we call the father of arthroplasty um or modern arthroplasty, thinking about the the the kind of the more modern low friction um joints. So realizing that actually you can't just replace the femoral head alone, which is what these these other chaps did you need to think about replacing both sides? So his pioneering work was on using a plastic acetabulum. So the socket with a polished metal stem that sat in amongst a um PMM. A so polymethane, methacrylate cement. Um, so it's a, an acrylic, a plastic cement. Um, the equivalent to that in, in kind of civilian life as you might call it. Um, is, is perspect. So it's a cold setting plastic. So that's a little bit of the, the history of it. Since then. These, we still see these Charnley, um, implants around and about these days, um, in some of the slightly older people, but since kind of late nineties, uh well, actually, probably a little bit earlier than that, we use a slightly different style of implant, which I'll come back to in a moment. So it's about history of things. Um in terms of how you get into arthroplasty if you're interested in orthopedics, um th this is a kind of um standard route that somebody might take to get to an orthopedic consultancy starting with your undergraduate training, which is where I imagine most of you at the moment during your foundation training, you might get a little bit of exposure to arthroplasty, um kind of coming into theater in taste of weeks. But it's usually as you get into your run through post or certainly your, your higher specialty training that you're really going to start to experience and encounter arthroplasty as a, as a operating surgeon rather than just an assistant. So in the junior years of, of um run through training. So ST 1 to 3, your main exposure to surgery is, is trauma and there's occasionally you'll get a job, um, or a, a post in, in training, um, in orthoplastic, but generally you'll be an assistant and won't get much knife time as we call it to actually be doing this, the surgery yourself then in your middle years. So, ST 456, you may end up, um, doing some solo trauma operating. So that's pretty common and you might end up doing some supervised arthroplasty. So this is when you're picking up the, the principles of arthroplasty and then it's only really in your final years um of ST seven and eight when you might get some less supervised arthroplasty and later on, you might do some solo arthroplasty. But um with quite a lot of backup for it and in your final years of ST seven and eight, that's generally when you're um kind of picking your focus and picking your career path. So often people will then in these last two years pick jobs that mean that they'll get more exposure either to arthroplasty or to trauma or to foot and ankle or somewhere a little bit more subspecialist. So as I say, arthroplasty tends to be a bit later in your training that you start to get the actual um first surgeon and then very later on the solo operating and arthroplasty because there's a lot to think about with it. So we've kind of whizzed through a bit of an introduction to it and now I'd like to talk to you a little bit about the principles of lower limb arthroplasty. And again, this is mainly thinking about um hip arthroplasty, but a lot of the principles of hip can be then transferred over to knee. So here's a, a um, a slide that sends a lot of orthopedic registrars into connections. So they, they get quite scared thinking about what we've got here, which is a free body diagram. So this is something that as you get to your um exit exams. So the the the fellow of the Royal College of surgeons in trauma orthopedics you'd expected be expected to draw. But again, what I'm putting up here is just a demonstration that there is a lot of science and biomechanics behind what we do as hip surgeons. So what we've got here is a diagrammatic representation of the femoral head in the acetabulum. The blue arrow going down is the force of the body weight and the green arrow on the other side is the force of the abductor. So the hip abductors and those two are in balance in this diagram. So what we think is that the force of the um abductors is the same when multiplied by its lever arm as the force of the body weight. And what I mean by a lever arm is the distance that the force at from the center of rotation. And if you think about it a little bit like a seesaw, if you've got a seesaw that's uh equal on both sides, then one child will equal one child on the other side of the seesaw. But if you've got a seesaw that's got a short bit and a really long bit, then you're gonna need more Children on the shorter bit to balance out the child that's on the longer lever arm. And that's the same with the body. And generally your body weight goes down the center and it's quite a distance from the hip, the center of rotation, whereas your abductors are quite close to them. So if you think about where they, they attach onto the greatest tranter, the figures that we generally use are about five centimeters compared to 15. And by some reasonably straightforward math, some might say it's complicated for an orthopedic surgeon. We can usually see that the body weight acts at three times the distance as that of the force of the abductors. And the important thing for us is that, that means the force of the abductors needs to be three times the body weight to balance it out. And why is that important? Well, we can do things that then help the patient reduce the, the power that they need their abductors. And that's a big part of what arthroplasty is about. So, in a path pathology, what we might see. So an example here, we've got a really quite severe hip arthritis is we can see that the center rotation which is this dot here has moved up and lateral and it's the lateralization of that. That's the real problem. And that happens because um osteophyte forms in the floor of the acetamin here. And that might mean that then the distance from the center of the femoral head here to the center of the body weight is increased. So instead of 15 centimeters, it increases to 20 centimeters. And that means now that this force that the abductors need to produce four times the force of somebody who's got um uh of the body weight as opposed to three times in the previous example. And that means that somebody who's already got weak hip abductors from their arthritis is gonna really struggle um to, to balance their pelvis. So what can we do as orthopedic surgeons to help with that? Well, arthroplasty returns that center of rotation back to the middle. So it returns into the original uh 5 to to 15 centimeter um comparison. So that ratio is now 1 to 3 rather than being 1 to 4. So that's one thing we can do. And the other thing that we do when we put our hip replacement in is we think about offset. And what offset is, is a line drawn up the mechanical axis of the bone and then the distance from the center of the femoral head to that mechanical axis. And if we increase that distance, then we increase this distance here and that ratio again improves. So somebody that's 5 to 15, that's a ratio of 1 to 3. And if we can increase that by a little bit, so just 2.5 centimeters, which is actually quite a lot, we never managed that. But just for numbers here, that's now 1 to 2. So this only has to produce two times the body weight's force as opposed to three. And that means that the patient is then able to cope a lot better. So the two big principles of hip arthritis are restoring the center of the femoral head medially and increasing offset where possible. OK. Don't worry about that for any exams, but there you go, there's a little bit of a principle of um hip arthroplasty. So what we've seen there is a cemented implant in both the acetabulum and the um the, the femur. But we've got other types of fixation we can do and um it's been in recent years. So in the last 10 to 15 years that the um uncemented implants have started to come in to orthopedics. And there are some parts of the world where they basically only use uncemented. So in North America and places like Australia, quite a quite a lot of the continent and there's a lot of uncemented arthroplasty being done. And what I mean by that is rather than the cement that Charnley first proposed. There are newer materials which encourage bone to grow onto the implant or to go into the surface of the implant and it's what we call a biological fixation. So, rather than pumping the femur full of cement, um, and then sticking an implant inside that and I'll come back to the kind of the, the, um, er, principles of that in a moment and we have an implant that you hammer in at, at, at, um, reasonable force. It's got what we call a press fit that it goes very tightly into the bone. And then you have a biological fixation where the bone that's surrounding that then grows in between the sprayed on surface of it or the 3d printed surface sometimes or it has a coating on the outside of it. Usually um what we call hydroxyapatite, which is, you'll, you'll know is a, is a component of bone and then the bone that surround that is encouraged to grow into it and that's got a very, very strong um er um interface between the bone and the, the implant. There are some issues with it. I won't get into that here, but there are pros and cons of of both types of fixation and we can have that of either the um uh the, the, the stem or the, the acetald. So the kind of counter to that or the opposite side of that is, is a cemented implant. And we've kind of mentioned the, the femur and this is an example of what, what I use for for most of my patients and is a exeter contemporary cup, which is a high density polyethylene. And then in amongst that, we have um a, the PMM, a cement which we force the cup into um the, the cement then interdigitate. So it, it kind of forms little fingers into the bone of the acetamid. Um and then it acts as what we call a grout. So rather than being sticky, it sets and um those little fingers hold into the bone a bit like a rock climber, wedging their hand into um crevices and a rock and it holds the um the implant in place. So then the uncemented implant usually comes in two bits in that. We've got um a metal shell which is quite thin and then a plastic poly er sorry polyethylene um component that then locks into that. So it's got a highly polished inside to it sometimes with a few screws which increase its strength until the bone grows onto it and then with a plastic component and then sits inside that. So then in terms of the stem, so we've mentioned the um uncemented, the cemented um implants for the um acetabulum. This is an example of the type of, of, of stem that certainly I use for almost all my patients. I don't generally do any uncemented stems. Um But again, this is something that's got a um a mantle of cement that sits around it. Um And then it's a polished metal surface um that sits in amongst that stent that, that cement. And the reason why it's polished metal and it has this taper design to it is that as the um, the er metal stem is pushed into the cement over time, it then actually gets more stable um because it slips in like a wedge going into a kind of a socket and it, it, it um has that in three planes So it keeps its motion. So it's stability in rotation and in um kind of um forward to backwards. So an to your posterior, as well as um lateral kind of planes for that. So then there's a few different options you can have for uncemented stems. And again, they have the similar um properties to, to what we talked about with the um uncemented um sockets is that they have press fit. I mean, we, we bash them in very, very hard. Um but it depends on where it's coated with the different materials for the bone to grow onto. So it can be around the proximal part. So down the metaphyseal part just on the diaphyseal or the whole whole thing can be coded and those have got their own pros and cons to it. Um And often we might think about differences depending on whether this is a primary operation or whether it's a revision operation where we don't have much bone left proximately. So we want to a fit distally, things like that. And the final thing to say that you often get with um uncemented implants that you might not get with a cemented. One is, is modularity in that we often use implants like this for um revision surgery or for tumor surgery. More complex surgery is that rather than having one size that fits all or off the shelf sizes, we can make a bit of a kind of a custom um prosthesis by putting the different bits together. Um, and uh countering, you know, problems that we might expect. So that's the kind of the principles that's a little bit about the materials that we use and the design of the implants. Um, but it's worth mentioning something about the complications that we see in arthroplasty. So, although arthroplasty is expensive, so the, the kind of cost we're thinking about for a hip or knee replacement is somewhere between 12 to 15,000 lbs in the UK. Anyway, they're very cost effective. So we talk about er, qualities which you may have heard of before, which are um, quality adjusted life years. And it's one of the most cost effective things you can do um in terms of a, a surgical treatment, second only a hip replacement anyway, second only to cataract surgery because patients get a lot of benefit from it. Their quality of life has improved dramatically and it lasts for a long time. So probably greater than 10 years is actually on the, um uh, pessimistic side. And the figures I quote to my patients for a hip replacement is that only 20% of people will have a revision surgery within 20 years. So the vast majority last longer than 20 years. Or actually, that figure is slightly fudged because quite a lot of people are in the elderly category and they'll die before 20 years. So their, their implants will outlast them and the majority are extremely satisfied. So, in hip arthroplasty, we're talking about 98% of people being highly satisfied in knee arthroplasty. It's slightly less, less and probably around 85%. So, despite them being very good, they have rare but devastating complications. And that's gonna be your next question to think about is what are the complications of lower limb arthroplasty? And I'll pose this question for um, maybe a minute or so. So just type in and you can type multiple times if you want to um to suggest some answers here. So I'll give you, I'll give you a moment to think about it. Try to think of as many as you can. Good. It doesn't matter if you repeat your, your answers that somebody else has said. I think about any other ones. Fracture. Yeah. Brilliant. Couple of people I think infection dislocation, ongoing pain. Absolutely. Bleeding, loosening of the implant. Yeah. OK. Excellent. So we're getting a, a load of really interesting ones coming up here. I'm just gonna put my slide back up again. So these are, these are slightly more rare ones. So infection we've meant or we've mentioned instability. Um That kind of includes dislocation, nerve or blood vessel damage. That's very rare, wear and loosening, possibly leading to revision surgery. And then all the medical complications that we might see. Um basically thromboembolic disease is the big one. So, pulmonary embolism, deep vein thrombosis, um myocardial infarction, stroke and death. So your chance of that are one in one in 1000. So 0.1 of percent. Um but still, obviously a major problem. And what I usually do when I'm consenting a patient for surgery is I would split things up into common things that happen less common and rare and a lot of these things are rare. So infection for a hip and knee arthroplasty, somewhere around 1% instability and dislocations kind of 2%. So a little bit more common. Um nerve vessel medical complications like these are significantly less than 1% caveat to that though is pulmonary embolism. That's a symptomatic medically significant pulmonary embolism. So a lot of people will have pulmonary pulmonary emboli after a surgery on their lower limbs, but they're tiny little ones that don't cause them any real major problem with that. So these are kind of significant life threatening. Um Pulmonary emboli, let's just flip back back to the slide and see if anybody's added any other ones, bleeding, pain and bleeding. They are relatively common So, bleeding, I'd say to my patients, they lose 250 mil of blood for a hip and negligible amounts for a knee replacement. So we do them with usually not very much blood loss. But another caveat to say to that is as the surgery gets more complex. For example, if it's revision surgery, then our risks are gonna go up quite significantly. So the risk of a primary knee or hip replacement is 1% risk of infection. But for vision, it's going up to 5% and dislocation instability, things like that go up as well with that. Ok, let's pop our next slide up. So, um any special, so we've got a question here. Um Any special considerations for patients with rheumatoid arthritis and history of trauma with long term systemic steroids and biological immunosuppressants? That's quite a compound question. Um Yes, you know, the, the important part with arthroplasty in its, in its diagnosis, in its um uh kind of planning the operation and its consent process is it should be individualized to a patient. So things like rheumatoid arthritis for the knee, we might worry a little bit more about instability. So they're more likely to have ligamentous laxity, they're more likely to have sinovial problems. So, synovitis. So we might think about doing a sinusectomy, um history of trauma. Yeah, we might think about, well, you know, can we do our standard referencing? So for example, somebody that's had a femoral shaft fracture, we might not be able to do intramedullary referencing for a knee. So we might think about other things like that biological immunosuppressants. Um, you know, we've, we've moved on for the days where most people are on methotrexate for a rheumatoid. Um, so methotrexate these days we continue with during the course of the treatment, but biologics, it's individualized of whatever treatment they're on and it's often done um, as part of a multidisciplinary approach, with the advice of the rheumatologists, we often have guidance from major orthopedic institutions like the American Academy of Orthopedics or er, the British Orthopedic Association, um who have um guidelines on what to do with them. But, but as I say, the, the key part there is it should be tailored to the patient and to the patient's medication and presentation. So I think we've got, we'll spend maybe 20 minutes looking at some case examples. Um And then if there's time at the end, we'll see how we get on with um a little bit of chat about um education. But you know, the focus of this will be the arthroplasty. OK. So what I'm gonna do here is put up some x rays. We'll start with relatively easy questions and see what you get with that. So our first question is gonna be on uh this series of x rays. So, uh let's pop our picture up here. Where is that coming up? Here we go. OK. So simple question here. What is the diagnosis? We've got an ap pelvis and we've got a lateral of a hip and be as specific as you can with your suggestion of what the diagnosis is here. I'll just give you a moment, maybe 30 seconds. I'll hide the answers here that people have put in and, and see what you come up with. Ok, let's re review what we've got a right intracapsular neck of femur fracture. Excellent neck of femur fracture. Um I wouldn't say there's much osteoarthritis going on there. Um I might say it's pretty normal hip joint looking, but certainly we've got a neck of femur fracture, don't we? And you're quite right. It's intracapsular is the important part of that. So let's go back to our patient and see what the details are. So this is a 35 year old cyclist whose bike has slipped on ice. We just look at how we're gonna interpret this X ray. What I've drawn on here is Shen's arc. So this is a line. If you follow up the medial cortex of the femur should go up the femoral neck and then go round beautifully into the obturator foramen. So, going along the superior pubic remi um and we can see it's perfectly normal on the left side, but if you look on the right side, we've got it stops there, that line comes up and you can also see that the um the leg is shortened and er kind of displaced laterally, this lateral view, er we'd expect to have to be able to draw a line straight at the femoral neck. So here's the, the anterior and posterior femoral neck intersecting with the femoral head. That's not the case here. So, we're right in saying this is an intracapsular neck of femur. So this patient was treated. Uh oh, in fact, here we go, we've got another little bit about um the importance of er anatomy when we're thinking about hip fractures. And again, it's something that orthopedic surgeons will bang on about particularly during your orthopedic uh attachments. We'll quite like to ask F Ys, you come to theater about this as well. So you don't escape when you, you're a post graduate. But basically, we split the proximal femur into three segments, excluding the femoral head in inter capsule fracture. If it's um medial to the, the attachment of the um joint capsule, intertrochanteric fracture, and then below the lesser trochanter, that's a sub subtrochanteric fracture about five centimeters below that. And then it's a femoral shaft fracture. And the reason that we're interested in that is this diagram on the right hand side here, the um capsule attaches just around here. And that means that if you have a fracture medial to that, then the retinacular vessels which are the blood vessels that go up closely adhered to the femoral head will be at risk if it's displaced. And that's the only blood supply that you get to the femoral head. Although the only significant blood supply, the other supply is through the artery, the ligament and theories. But it's tiny in adults who are completely obliterated. More important for Children when they have a phys that crosses here. And that means if you have an extra capsule fracture, we don't worry so much about the blood supply to the femoral head. Cos it'll include this little bit of the medial circumflex artery here. So, intracapsular fracture, we worry that the blood supply here is, has been rogered and generally, we're going to dispose of this and do some sort of a arthroplasty to replace that femoral head. But what have we done here rather than arthroplasty in this patient? We've done a sliding hip screw, which is this part of the er implant here. And we've done a uh a cannulated screw in addition to that. And if you look at this picture, which was taken two months after the operation, it looks quite a bit different to the interoperative view. So things have been beautifully reduced in the operation. The, the um bowls been put back on top of its um, its golf tee and the cannulated screws head is hard up against the edge of the, the bone on the lateral side here. Compare that to this at two months where things are beginning to back out. Seven months, things have almost completely backed out and we're gonna see the the barrel of the screw, sorry, the, the screw coming out of the barrel. And also importantly, if you look at the shape of the femoral head here, it's flattened and collapsed down. So this patient has gone on to develop um, avascular necrosis. So their, their femoral heads collapsed. And it means that those arteries that are up here were damaged beyond repair. And they've gone onto that. And what we've ended up doing is removing the metal work to see if that's improved, the patient's pain. It's not, you can see the tracks of the femoral, of the, um, metalwork and a completely squashed femoral head, 35 year old. That's not gonna be particularly good to go on their day to day life. So then they've had a, a beautifully done hip arthroplasty on the other side. So my next question to you, given that history and what happened is, was the initial treatment, correct? So, this is a yes or no answer. People being hesitant, I have to, I, I'd, I'd remind you that this is, this is completely anonymous. So there will be no, um, identification of, of correct or, or not answers. In fact, can we see what people are saying? I suspect that's the yes at the top and no at the bottom. Ok. Can somebody just type and chat if they 100% if they've typed? Yes or no is option number one? Yes. So I can't see them labeled in this one. So, for us, um, it doesn't say they're just both blank boxes. Oh, are they? That's a bit of a failure then, isn't it? Ok. Um, what I'm gonna do is edit that. Oh, yeah. Ok. Yes and no explain now. Oh, there we go. Ok. Now I've, I've forced people who've already answered that. Yes. Is there? Ok. Let's pretend that's, that's correct. Um, I would agree with everyone who's been forced to say yes, the treatment is correct there. And the reasoning for that is, that's a 35 year old person. And if you reduce and fix in situ a fracture like that, they've got about a 70% chance of it being successful and them avoiding a hip replacement. So if you do that in seven out of 1035 year olds, then those people will go on and not need a hip arthroplasty immediately or, you know, within AAA decade. Um So if you replace those hips, then, you know, you'd be doing a lot of people who might keep their own hip for a bit longer. This person's been unfortunate. Um, and they have um, gone on to develop, develop, am so, yes, I think the treatment there was correct for this person in an elderly person. They're not gonna be as put out, it's not like they're gonna be subject to having multiple revision operations over their life. So we generally go in an older person, they're displaced into a capsular fracture. We'd go straight to an orthoplastic of some sort. Ok. So I'm sorry for that technical error in uh sorting out we clap. So let's go to the next case. Then we have a 75 year old who's got some groin pain. Now, have I got a question on what the diagnosis is here? No, I've not. Ok. So let's just go to this bit. So this person has been seen in the outpatient clinic with deep left groin pain and the X ray, we can see shows pretty, pretty nasty hip arthritis. So hip osteoarthritis. So we've got lots of joint space. We've got cysts, we've got sclerosis, we've maybe got a osteophyte. So they've been seen here and we've listed them for a hip arthroplasty. Um, a year has gone by as things do post COVID and they come back to their pre assessment clinic for their actual pre op check and we're getting an, an up to date X ray at this point. Ok. So here's what the, the picture looks like now. And er, the question here is what has happened since their initial listing. So this is the most recent radiograph, what's, what's changed, what they developed? And again, we'll give you 2030 seconds too. Uh, make a, an assessment. A VM somebody's put excellent aide. Good. Ok, just for time or maybe just switch forward a wee bit. So what we can see is, um, the femoral head has collapsed and there's a big load of sclerosis around here. So we're actually kind of fairly far along the line that it's collapsed and that it's already had, had a chance for it all to collapse down and then become sclerotic. And if we think about the classification of, of, of AVN, the earliest part of AVN is before you actually see any radiographic changes. And it's actually, it's an MRI diagnosis that we begin to see. AVN. Then you get to start to see um changes around the usually the weight bearing surface in the superior femoral head and you might see some cysts in it. And then as the bone cells have died and they're no longer turning over, they're no longer repairing the bone, it crushes down. And then the final stages of that is when you start to have that then causing secondary erosion and arthritis of the acetabulum. So we've got that here. We've got change in shape, collapse of the femoral head and it's pretty miserable for the patient. It may happen suddenly or it may happen over a few months um with, with this patient and what they've gone on to have is a, um, a hip arthroplasty fill up. Ok. So next case, we've got a 68 year old who's had a um arthroplasty maybe a few years ago, they got back to doing what they like doing. And one of those things is, is tennis, maybe, got a little bit over exuberant during a tennis match dived to um return a serve landed awkwardly and they come into coming into the emergency department with, with this injury. So the next question for you is what's your emergency department management of this patient? So as many things as you can think, think of this patient has come in on a um on a stretcher. That's this appearance here. That's the metal bit. What are your thoughts on the emergency department management? So everything that you can think to suggest for, for this patient and again, you can type something out, submit it and type out something else once you've submitted that. Ok. So IV access. Yes. Pain control. Yes, analgesia. Yes, at assessment. Yeah, good. So, you know, trauma happens or fractures happen through trauma. So we want to be thinking about um you know, has the patient sustained any other injuries? Um keep him flat. Yeah. Fine. Uh bleed Ortho. Yeah. Ok. Um We're gonna get involved at some point. But yeah, absolutely. So there's a few things to do. Pain control. Absolutely. And then we want to do something to straighten this out and to stop the blood loss that you'll get from a fractured femur, which is effectively what this is, although it's peri prosthetic, um there's, there's a femoral fracture, so they're going to be bleeding quite a lot. So, uh what we want to do with this patient is, and here, here's the actual x rays from this same patient is, this is a Thomas Splint that's been put on this patient, um, which draws things out to length. You can see the difference between that. It's all smashed to pieces. It's, it's, um, given longitudinal traction and reduces slightly. Um, and, uh, just a bit of history about the Thomas Splint. It's one of the orthopedic devices that save more lives than I think anything else since its invention in the first world War in the first World War before the Thomas Splint, femoral fracture and mortality was 90%. Introduction of the Thomas Splint down to 10%. So it's, it's a pretty, pretty major, um, er, orthopedic innovation and we still use variations of it today. So this is the kind of thing that's done for this patient. Oh, my next question. Actually. Here we go. Oh, hold on. I think we've got an issue with that one as well. There you go. You've got some options there. Does the stem look stable or well fixed? And I'll put my images back up here. Yes. No, unsure. Ok. So glad people aren't saying yes. Um, but I think there's a reasonable split between no and not sure to my eyes looking at that, that stem is, is completely burst apart. So there's no support for that stem whatsoever. And there's a classification system we, we use called the Vancouver classification system which has different bits to it. But one of them is, you know, this is visibly unstable and this needs something more than just, um uh you know, just putting things back together. Um, and, and another part of it is we're not really sure if it's unstable, so we'll check it during the operation. So, you know, as an orthopedic surgeon, you, you look at an X ray like this and make an assessment, you know, do we need to do something to replace the stem? And you know, th this stem isn't just gonna be able to cable things back together. And certainly that's what's been done here is that this is a, a different implant that's been put down. It's got a long stem on it to get to a bit of the bone which is not fractured. So if you look here, you know, this is quite a distance away from the, the tip of the, the implant that um the fracture extends to. So it's smashed to pieces. So we've got a long stem with a new implant and then cabling everything back onto that. OK? I think this is the final case to do and let's just pop our next question up. OK. So your question is, where is the abnormality here? So these are the two same pictures, just one zoomed in a little bit. So you might want to use the zoomed in to answer and you can click on multiple, multiple spots. So where's the abnormality? It is a good sprained. These are always great. I like seeing um, these ones and there's just dots all over the shop. I think when you see the abnormality it's eas easier to see it with a retrospectoscope. But unless you're looking at these really closely, a lot of the time, it's sometimes a bit difficult. Ok. So some people are getting close here, some people are getting close. So let's pop up on screen what's going on. So if I draw an outline over a difference that you can see in that right hip, what I'd like you to look at is cortex coming up here. And then there's something funny going on here, compare the color here to the color or the, the um brightness up here compared to here and compare what that greater dander looks like to the other side and to my eyes, there's a lytic lesion in this proximal femur. So I'm just gonna go forwards and backwards a few times and actually sometimes squinting and taking a step back with the resectoscope. As I say, you can see there's something going on here. So this patient has gone on to have an MRI scan and a CT scan. And there's been two things. So this is a 34 year old, they've got severe hip and thigh pain. It's been uncomfortable and waking them at night for maybe nine months or so. But then relatively recently, it's got much worse and the MRI show the MRI and CT Combined Show two different things. One is probably a fracture through that remaining cortex that's sitting here and there's a very different looking invasive um lesion in that proximal femur. So anything that's going outside of the bone is malignant. Um so it's not benign, benign things stay within the bone, but this is going into the surrounding muscular tissue around it. So this is, this is pretty nasty, this is a a um bone metastasis most likely. And the kind of things we're thinking about with bone metastases are, you know, where do they come from? And you may have heard the er the lead kettle. So, um BK TL um um acronym or Pneumonic to remember. But this, this is a, a slide that just outlines where the, the most common uh origin sites are for am uh metastatic bone lesion. And so this patient will have their CT and their MRI looking at the, the lesion itself and then we'll get probably a full body ct or certainly chest abd or pelvis to look for a source of the primary, about 90% of bone tumors are, are secondary metastases and only 10% are um are are primary lesions. So, the two things this patient has had and I think this patient, it, it was found to be a, a renal cell carcinoma. So it came from the kidneys. One of the issues with the renal cell carcinoma is that the um the metastases that they, they um cause are extremely vascular. So, in working up for their later operation, one of the things that we do is um uh uh uh um clipping or um uh basically interrupting the blood supply to the, to the thing. I can't remember the word. It's disappeared from my mind for a moment. Embolization. That's what I was looking for. So it's a catheter going in with a, an arteriogram and then they um embolize the arteries that are going to the affected area. So it doesn't bleed and that happens before the operation. So it needs to give time for then the um the uh renal cell carcinoma to, to then shrink a little bit to become less vascularized and then we can go in and do the operation with a less risk of bleeding. This person has had um proximal femoral replacement um with their, with their um acetal replacement as well. OK. I think that's the end of my questions here. Yes. And that's the end of my slide. So I'm, I'm going to open up to questions if anybody's got questions about arthroplasty, any of the case that we've just talked about. Any of the things we've talked about, you know, how one gets into arthroplasty? Anything like that? Do do feel free to, to fire away from now. And thank you for listening. OK. So the question, what factors influence periprosthetic fracture management between revision and fixation. So probably the main one is what we kind of saw there is whether um, the, where the fracture is in relating to the, to the implant. So, if it's a tiny little avulsion, so, you know, we, we do see fractures which are just the great tranter, just as, as, as fractured or um, something that's, that's completely undisplaced, we might fix in situ um, you know, periprosthetic fractures happen around the knee as well. Um So the, the location related to the implant will dictate how we, how we manage that. Um, and the, the kind of the main thing that we worry about with a, um, periprosthetic fracture is whether it's interfered with the interface between the, er, the implant and the bone that it's sitting in because what we don't want to happen is we fix something but we don't quite fix it properly and then everything rattles about and causes kind of secondary problems with it. So, part of that is you can make a diagnosis of an X ray if it's very obvious like we've had there, if it's very obvious, it doesn't involve anything that would cause it to be um, er, unstable and then there's the interoperative um assessment. So some of them, you, you think they look ok and then you go in and it's a mechanical wiggling the, the implant and, you know, does it move up and down in the cement mantle is the cement intact. It's a little bit difficult sometimes to, to tell from radiographs whether the cement mantle has been breached um because X rays are, are two dimensional pictures and it's a three dimensional objects. So there's a little bit of combination between the radiographic appearance and then the interoperative appearance. And often when you're managing um a fracture like that one has to have multiple plans. So plans A B and C or plan if stable plan, if unstable. And you know, one of the, the big bits of advice for er people going into these is, is make sure you have the implants to revise if you're going into it. Um I know, you know, even if you're pretty sure you don't need to revise it, something might happen interoperatively. So that as I, as I say, that that's the main, the main um considerations with it. So question what influences choice of material for the socket in a total hyper arthroplasty. So sorry with polyethylene a lot of that's surgeon's choice. Um Personally, I don't use ceramic um implants. And my reasoning for that at the moment is that um it doesn't buy you that much more. We kind of improvement. There is a slight rare improvement, but the risk of a ceramic implant is that ceramic is very hard and it's very, very low friction, but its hardness means that it's quite brittle. So um when it breaks, it breaks catastrophically. Um and um when ceramic breaks, ceramic is, is made out of, II mean it's kind of sand basically that's been put under very high pressure is that it breaks and then releases tiny, tiny fragments and basically fills the joint with sand and that then causes a lot of problems later on. So it's pretty catastrophic if, if a ceramic implant fails. And in recent years, we've been promised that the most, um, advanced ceramics don't fracture. But the fourth generation ceramics is what we're on at the moment and we've had two or three of them in our unit in Edinburgh. And we don't do very many. So, you know, I II don't see the advantage to using it over um a polyethylene implant. Um and a metal head. So the only, the only um kind of people that would use them maybe in very young people who aren't particularly heavy in their overall um uh body weight. So, if you have somebody that's an overall body weight, that's kind of 100 kg or more, you probably wouldn't use, wouldn't use one, somebody's going to be doing activities where you've got a sudden shock going through the legs. So, you know, horse riding long distance runners, things like that, you might want to avoid it. Um But, but certainly for the socket, all of mine are polyethylene. Um I only use metal heads but there are some people in Edinburgh that use ceramic. So it's, it's surgeon preference. Um But, you know, there, there's a little bit of evidence behind it. Next question is, is there an age limit for arthroplasty. Um And what other factors would influence your decision to not offer patient arthroplasty? So in answer to your, to the, the first question, is there an age limit? No. Uh I say that to a lot of my patients is that there isn't age, doesn't come into the equation, but the medical comorbidities that come with age do so as you get older, you're more likely to have medical comorbidities. So you're more likely to have heart disease, lung disease, diabetes, all these kind of things. And those are the things that affect the risk of doing an operation. And as people get older, you get more of them. But if somebody's very poly, um, comorbid, then I'll refer that patient to a anesthetic preassessment clinic and they go through the operation with the patient, they go through a calculated risk. So they'll tell the patient, well, you know, you've got a 10% risk of dying within a, a month and a whatever percent risk of a major complication, whatever percent risk of um, a one year mortality. And at the end of the day, if the patient is accepting of that, and they say I would rather die than go ahead with the pain that I'm in, then we'll do the operation. But there are enough patients that then say, actually, do you know what I can cope with mobilizing in a wheelchair? So I'm gonna avoid the operation and there are some people who I very strongly advise not to go for an operation because their risk of on table death is so is so high. So, you know, it's not age, it's the problems that come with age that they are, they the the part. And I think that hopefully kind of even influences your second question of what factors influencing your decision or not to offer a patient arthroplasty uh offering arthroplasty is a uh uh interaction between you and the patient. So II don't like refusing someone AAA joint replacement. And you know, there are some people that would do once their BMI. So their, their body mass index reaches a certain threshold. I wouldn't do that. I often have a discussion with the patient of, well, this is an elective procedure. Let's get your body mass index as low as possible to make it as safe as possible. Um And then there are some people who try very hard but can't get below a BMI of 45 or something like that. And at that point, we then say, OK, well, we as a team, you and I as a surgeon and patient accept the risks and then we do the operation. So next question is, what are the attractions of lower limb arthroplasty compared to other orthopedic subspecialties? Are there any downsides the attractions with lower limb arthroplasty? Is the outcomes are about as good as you could hope for in surgery? You know, I don't I don't think other than, as I say, other, other than cataract surgery, I don't think you'll find another procedure that patients love more than a hip replacement. Um, you know, 98% of people are giving you two thumbs up with hip replacement, in particular, the thumbs go up almost as soon as they wake up after the operation. So it's incredibly rewarding. Um, it seems like you're doing the same procedure again and again, but actually each patient's slightly different. There is challenges, there's a bit of carpentry, there's a bit of playing with mechano, there's material science, there's all kinds of things to think about. So it's a challenging thing to do and you can subspecialise even in arthroplasty. So you could be a, you know, a vision surgeon, you could be a tumor surgeon, you can do all kinds of things with that. So I would say those are some of the, the advantages. Other thing, if you only do arthroplasty, your own calls are pretty good. So, you know, you won't be in at midnight in your late fifties, early sixties doing anything. Um Like some of the trauma surgeons are might might my own call is pediatric trauma. So I am in at two o'clock in the morning doing things and I'd prefer not to be. So there's advantages there downsides to it. You know, I guess there is an element that you do get into habits and you, you're seeing often pretty routine stuff. But, you know, there's, there's enough variation in it. Um, it's very demanding the patient sometimes because it's elective surgery, they expect a lot. Um, and when complications happen they are personally, um, devastating. So, you know, if you have a patient who's got an infection or there's something that, that hasn't quite gone as planned during an operation, it, it, it does weigh in you and it does cause a lot of stress from that point of view. So, you know, the personal responsibility is, is, is high with that. I would say it's a great thing to get into. Um II, that's the bit of my clinical job. I enjoy the most. Ok? I think we're a bit over an hour there unless there are any other questions coming in. Um Should we, should we end things there? Yeah. So thanks very much Mr for giving such an interesting talk into an area of orthopedics. Um and also some really great questions in the chat. So thanks very much for coming along today guys. I've posted a feedback like into the chat. I'll resend it just to see people scrolling. It'd be really great. So if you could just fill that out, it helps us provide better talks in the future. We're also running several other talks as part of the Subspecialty series. So the next talk is our pediatric spin talk, which is on the fourth of December at 6 p.m. Again, I'll pop a link into the chart so you guys can sign up for that if you're interested. And again, please start the feedback. If you attend most of the tops in the series, you also get a personalized certificate. So there's that as well. Once again, thanks very much for coming along and thanks to Mr Brown for taking the time out for your evening to come along and do this pleasure. Thank you all for attending and for engaging in the, in the questioning. Have a good night, everyone.