Perfect. All right. We'll move on to hip dysplasia this point. Fortunately becoming a little bit less common overall, which is great. Some of our selective breeding programs have been, been helpful in that regard. So hip dysplasia is another, kind of early developmental disease where these animals have abnormalities in, especially the soft tissues of their joints. So, remember the joint capsule and the capital ligament or ligament of the femoral head has a bunch of different names, those structures should normally be nice and tight, and they should hold the head of the femur nice and securely up against the acetabulum. And then as the animal grows, the head of the femur, the acetabulum should grow together such that the, such that they remain in good apposition and there's good congruency. You know, they should fit together nice and smoothly. And so that should be a process where they are growing together. If the soft tissue structures are too lax, then that means that the femoral head may not be adequately contacting or may not be contacting in an appropriate place, the acetabulum. And so over time, we start to see that the acetabulum may not develop, you know, that nice rounded appearance such that it can easily cup the femoral head as they grow. You know, we tend to see that the acetabulum might stay more shallow than it should be. And so if that happens, then we don't have very good dorsal coverage in support of that femoral head. So when they're weight bearing then they have a tendency to subluxate the joints to some extent. Additionally, if those bony structures are not growing and developing together the way that they should, that again sets them up for abnormal force distribution across the joint that sets them up, then for damage to the articular cartilage, progressive osteoarthritis. So this is kind of an interesting disease process because we can identify these animals at slightly different stages in their presentation. So often we think about animals with hip dysplasia presenting young. And many of them do. And when we identify it in these young, large and giant breed dogs, often they're painful, primarily because of hip laxity. If I go back to this picture that I had on the other side, look how far away this dog's femoral heads are from the acetabulums. Obviously, you know, this is a pretty extreme case. That's why I put it in there, because I really wanted to kind of emphasize what I was talking about. You know, but the, acetabulum is a mile away from the femoral head here. And so if this animal is walking around, since there's such poor dorsal coverage of this femoral head, it's going to be able to subluxate. And so when it does that, that's going to be tugging on the joint capsule, tugging on the ligament of the femoral head. Those are very well innervated structures. And so often those guys are quite painful when they present. And they might also have gait disturbances. A lot of times when they walk, especially severe cases, they'll, kind of move their back in together as one. So we call that bunny hopping. And so they'll often have gait disturbances. They'll be painful with hip manipulation. They'll often have hind limb muscle atrophy. Look how little muscle mass this dog has visible in this radiograph. You know, this poor dog is really like offloading its, weight bearing as much as possible to the forelimb, because it's painful when it's trying to use its back legs. 

Okay. So that's generally what we see in the young dogs who come in who have hip dysplasia. They're painful because of hip laxity primarily. But with time, like we said, these guys, as a result of their abnormal hip morphology and abnormal force distribution, they're going to start to get degenerative changes in their joints. That's actually going to reduce the hip laxity because part of joint degeneration is actually thickening in periarticular fi, like thickening of the joint capsule periarticular fibrosis. It's just like the animals with cruciate ligament tears who come in, who stifle is now, you know, super thick, because the body's response to that abnormal laxity is to lay down fibrous connective tissue. And so that's going to get rid of some of that laxity. You know, and in an extreme case like this one that I have the radiograph of, that's probably still going to have a lot of laxity. You know there's only so much we can do. But for more minor cases the laxity is actually going to improve as articular fibrosis occurs. So a lot of times the animal actually starts to feel better because now they're not subluxating as much. You know they've got some early degenerative change, but the hip is actually like the shoulder a fairly forgiving joint. And so, they're probably going to have a little period of time, you know, when they're like a year, two years, maybe three years where they're better, you know, they're more comfortable even without doing anything to them. But then we see them come in again when they're getting older, because at a certain point they develop enough degenerative change, enough damage to their articular cartilage where they start to be painful again because of the DJD. So now they're not lax anymore, but now they're painful because of their osteoarthritis. So we do see with hip dysplasia this bimodal presentation. We see the young dogs present, they're painful because their hips are lax, and so they're stretching on those painful soft tissue structures. And then we see the older dogs come in, they're not lax anymore, but they're painful because they have, degenerative, bony and joint changes now. 

Diagnosis. Generally, this is something where we can get by with just our plain film radiographs. This is not something where generally we would need a CT or an arthroscopy or anything. We're actually really good at looking at hip dysplasia on our plain films. So in a juvenile I've got here some examples of what we might see, and I've got this guy back again, you know, this horrendous hip laxity. So this is a pretty extreme case where, you know, there's subluxation of the hips, where there's like zero coverage, dorsally, with how flat and abnormal in appearance this acetabulum is. But other than the changes in the acetabulum, the bones look pretty normal. You know, the femoral head looks like a femoral head on both sides. You know, it looks the morphology is quite normal at this point because this animal is so young and has not yet really developed any of those degenerative, bony changes. This is a more subtle example of the same thing. So if we drew an imaginary line across the dorsal aspect of the acetabulum to kind of mimic where that acetabular rim would be, ideally we'd like to see at least 50% of the femoral head recessed within the acetabulum. So underneath that little imaginary line that we draw. And so, you know, this is an example where, you know, it's not the worst. It's certainly nothing as bad as the picture on the right. But it's not the best either. Probably only about, you know, maybe 30% coverage of the femoral head, just to guesstimate. So we have poor, but more, we still have poor femoral head coverage, it's just a little more subtle as compared to, this dramatic example on the right. Once again, the femoral head right now looks pretty normal. But there's still likely, as a result of this, poor femoral head coverage, there's still likely going to be some degree of abnormal force distribution. And so this animal is still at risk to develop osteoarthritis over time because he's below that minimum 50% that we would like to see. 

In an older animal, the rads will look quite a bit different. So both of these cases have pretty significant degenerative changes, especially the one on the right. What we can identify in animals who have developed significant coxofemoral, DJD, degenerative joint disease, arthritis, I've been using these terms interchangeably, but I guess I should, you know state flat out OA or osteoarthritis is the same thing as degenerative joint disease or DJD. So those are interchangeable terms. What we can see is that the femoral heads now have become flattened, kind of mushroom shaped. There's often a rim of osteophytes that develop around the margin of the joint capsule. You know, we can see those over here, and we can see this abnormal, flattened, mushroom like shape to the the femoral head. And then we also see answering changes in the acetabulum. Again it's kind of shallow, it's getting wider, there's osteophyte development on the cranial and caudal margins, and so we see these more significant bony changes in older dogs. These take time to develop as compared to younger dogs who have relatively normal anatomy, but are painful because of their laxity. And we can often appreciate signs of hip laxity, via looking at the poor coverage of their femoral head. 

Alright. So there are a couple of screening tests that can be done to try and identify animals with hip dysplasia, especially ideally while they're still young, so that we can start lifelong management of osteoarthritis for them. The older technique is the, OFA screening technique. Those guys need to be at least two years old, so at least 24 months of age. And the nice thing about OFA is that you can submit radiographs that you take in your own clinic. You don't have to be certified to take a OFA rads. That said, when you send in the rads they do have to be very carefully positioned. So you know the picture over on the right there is showing a well positioned hip radiograph. You know everything needs to be very straight. The pelvis needs to be straight. The femurs need to be parallel. The patellas need to be centered over the groove. And all of this is so important because if we're just looking, you know, primarily at this, it's called hip pulldown or hip extended view, you know, the biggest thing we are looking for is this femoral head coverage and if the animal is tilted, that can either make the hips look better covered or not as well covered just based on an artifact of positioning. So we really, really need good positioning for OFA rads. Otherwise they won't be able to, adequately evaluate the animal. Alternatively, another screening system, is the Penn hip system. Currently it's available through antech. The thing with Penn hip is that, it does need in order to get certified, the images do have to be taken by a certified individual. And so that's not something where you can take the rads and then send them to Penn hip. They have, you know, one of their people has to it has to take them. Someone who is certified as a to take Penn hip views. So that is a little added complexity there. But the benefit of Penn hip is that we can do it in younger animals. So again, if we are doing OFA that animal has to be two years old. You know, a lot of times breeders are looking to make decisions about which puppies they're going to keep, which puppies they're going to sell early in life. And so if they are two years old, you know, that's that's less helpful a lot of times for, developing these breeding programs. With Penn hip, the animals can be four months old, can be 16 weeks old. And so that's, that's helpful. The reason that we can, do that and you know, why we, you know, do love being able to, to do Penn hip in these guys is because we specifically can look at how much laxity is present, because the series of images that they take includes a distraction view. So essentially, they have a view where they distract the femoral heads as far out of the acetabulum as possible and when we look at that distraction index, that ratio of how far they come out of the of the acetabulum, that is, quite well correlated with the likelihood that they will develop hip osteoarthritis in the future. And so if you have a breeder who, you know, is worried about hip dysplasia in her stock, then pointing that breeder towards, the Penn hip system can help with, choosing which of those young animals are going to be, the best candidates for, for breeding, at least in regards to, their hip health.  It can be very helpful. 

Right. Treatment for hip dysplasia. Almost always we'll start with nonsurgical management. And it's actually really effective. You know, I was a little iffy about how well dogs with elbow dysplasia do, but dogs and hip dysplasia again, this is a really forgiving joint. Sometimes you'll take an abdominal rad and you'll see that there's horrible hip OA and the animal is completely asymptomatic. It's running around, it's comfortable. It's great. And so, you know, again, this is a often a very forgiving joint. So there's a lot that we can do medically for these guys. Our primary concern, of course, is try to reduce and control inflammation of the joints and discomfort. So we can use NSAIDs as necessary in these guys. Obviously they're lifelong. Probably going to need more NSAIDs than the average dog is, so we always want to be judicious with our NSAID use. We also want to make sure that these guys are staying lean, engaging in lots of low impact activity, potentially considering a joint diet or, or fish oil supplementation again here. And then there's a lot of different adjunctive options out there, things like Adequan and various like pain control adjuncts like, acupuncture and you know, cold laser and all sorts of things that, you know, I think some of the evidence, unfortunately, can be a little bit iffy, but it is one of those things where every little bit might help these guys. And if we can reduce our dependance on NSAIDs, that's going to be great for their kidneys, is going to be great for their liver. But definitely the number one thing that I tell my owners of young dogs who've been diagnosed with hip dysplasia is to keep them lean. That, lean BCS is going to be the number one thing that helps to keep these guys comfortable. 

Once we get to the point, where that is not enough, or if we are trying to be preemptive about improving hip function, that's when we consider surgery. So we'll talk first about the surgical options that we have in juvenile patients. So the idea is if we are doing one of these techniques, the idea is that we are doing it preventatively. So we've identified that an animal has for poor femoral head coverage. So if you look at this radiograph on the left here again if we put our little line down and did our imaginary, measurement of how much of the femoral head is actually within the acetabulum, it's not a lot like what, 20% maybe in this dog? Just guesstimating. It's, you know, pretty poor. And so this dog we know has hip laxity. This dog is going to likely be at risk for developing DJD long term. And so we can consider an option to improve the coverage of the femoral head. So if the dog is very very young when this poor femoral head coverage is noted less than 16 weeks of age, so pretty rare that we find one that early. But sometimes it happens. We could consider what's called a JPS or a juvenile pubic symphysiodesis. And essentially what we do in those cases is we come in with a cautery pin and we go along the pubic symphysis and we burn the crap out of the, the pubic symphysis. It's a little a little more elegant than that, but not much. Essentially, we're trying to shut down the pubic symphysis, such that bone growth ventrally is halted. And so if we have less bone growth ventrally, that's going to result as the dorsal structures of the pelvis continue to grow, they're going to be tethered ventrally. And so that's going to result in external rotation of the acetabulum and improved femoral head coverage. So if we find a very, very young puppy with signs of hip laxity, great, we can consider a JPS.. Alternatively, most of them, unfortunately, are going to be too old by the time we, we pick up on that, they have to have enough potential growth remaining for that to even be considered as an option. But if they have passed that point, we do still have a, an option that we could consider to try and preemptively improve their femoral head coverage. And that's a TPO or DPO. So a double or triple pelvic osteotomy. It's just surgeon preference. They're both. The idea is the same. It's just do you make that extra cut or not? So this image is the same dog is on the the first side. This is a dog who has had a TPO, so there is a cut made in the ilium, a cut made in the, the pubis and a cut made in the ishium, and then that section, because then, then we have basically a free section of pelvis, that section of pelvis has then been externally rotated. And then now when you look at this femoral head, you see how he is now more recessed as compared to his pre-op. He's now more recessed within the acetabulum. We probably hit that 50% if we draw our little imaginary line. So hopefully this guy will now have improved function on this side. Less less discomfort because he's no longer tugging on those painful, well innervated structures. And hopefully he will, be less likely to develop DJD or at least develop it more slowly with time. Unfortunately for both of these, it is a little unpredictable how much of a difference it will make long term. Certainly our goal is that this would be a one and done. You know we do just the TPO and then he lifelong is able to be maintained with medical management. Essentially the goal is to try and prevent him from needing a salvage procedure in the future. Which in my experience has been pretty good. Again, the hip is a pretty forgiving joint, so, you know, this can be a good option. That said, we do have some good salvage options out here. And so especially if you have an owner who's a little hesitant to go forward with a, you know, procedure that does have a higher risk of complications, does require exercise restricting for you know, young dog for an extended period of time. Or if we're, you know, may we're not seeing any bony changes, but we're a little worried more about how does the articular cartilage look, because he's already, you know, 18 months or so if we're considering doing this. You know, in those cases, it's also completely appropriate to say I'm not going to do a TPO. He's too old for a JPS, i'm going to focus on medical management right now. And then in the future if necessary, look at the salvage option. 

So these are salvage options. We talked about them before when we were talking about avascular necrosis of the femoral head. Once again, we can either do an FHO or a femoral head neck excision if you want to be fancier. Or we can do a total hip replacement. For the little dogs with the avascular necrosis, I said I would totally my own dog just do an FHO because they do great with, FHO's generally. Some exceptions, of course, but, most of them do very well. In a large breed dog, you know, honestly, we can still do very well with an FHO, but they often, especially if they have disease on the other side as well, they often need a lot more support than the small dogs do postoperatively. So that's a consideration, especially because I feel like these large, heavy, you know, dogs with hip dysplasia, they always belong to like the 85 pound little old lady who can absolutely not help get the dog up. But, they also, I feel like, have more gait disturbance and tend to have a little bit more impact on their athletic ability as compared to toy breed dog FHO's. So it's a consideration. But you know, the benefit of an FHO is still that it is expected to help control discomfort, and it is way cheaper and way more available than the alternative, which is a total hip replacement. So total hip replacement should return normal or very near normal, athletic function to this dog. It's great if they have disease on the other side, because now they've essentially been given a normal hip, which can do a lot for them being able to get up and do normal dog things. But it's very expensive. If complications occur, they can be very challenging to deal with. So it's a big decision. You know, it's a lot going forward. But especially in these large, heavy, older dogs with bilateral disease, you know, I do feel like they benefit a little bit more from the total hip replacement over an FHO. Not that they can't have an FHO, but, you know, it is a little more or something that I would consider for my own dog versus if I had a toy breed dog, I would probably never do a total hip. There are people who do it, but personally, not me. All right.