Robotic Joint Replacement, Dr. Christopher Grayson

All right. Good morning. Thanks for having me here to talk. So first some disclosure I have no financial relationship with any of the companies here but I have been utilizing the Mako system which is from Stryker. It’s the largest of the robotic systems currently in use for about the past 18 months since we got it at our hospital, I’ve used it for probably 99 percent of the primary hip and knee replacements we do. So I’ll start off and talk a little bit about hip replacement first. So hip replacement our total hip replacement refers to resurfacing of the femoral and as a tabular side of the joint we replace this with metal components. There are four components in a typical hip replacement with a metal femoral stem metal acid tabular cup and then a plastic liner or ceramic liner and a ceramic or metal head on the femur.
So the surgery takes anywhere from one to two hours and with minor joint replacement techniques. As Mike just talked about these are patients that are now instead of staying in the hospital three to five days or going home the same day. It’s a big important thing we’ve done is out there our therapies are now working with the patients the same day of surgery and so often within a few hours at the hospital of a patient coming out of the operating room. Our therapies have them up and moving in the halls and that just helps the patient gain a little trust in that joint. And as we go to rapid discharge protocols has been extremely important. Patients have. Are having a lot less pain because our pain controls have improved substantially and we and virtually every patient home. The days of patients go into a rehab facility for two to three weeks are kind of frowned upon as we found they had higher risk of infection and readmission to the hospital.
However, everything is not perfect. We still have complications dislocations happen components come out now position leg discrepancies components fail and loosen early and then sometimes patients just have continued pain and bursitis and we have to wonder if those are indirectly related to component positioning. So when we look at how we define excellence in any particular field Ted Williams the last major league player to hit 400 for a season and Steph Curry a forty three point seven percent career three point shooter. These are the best of what they do they’re at the top of their game. But I don’t think anyone would be happy with an orthopedic surgeon who hit his target less than 50 percent of the time but this is exactly what we were doing. So a study from Harvard with experience joint replacement surgeons showed that when we were looking at our position of the hip that’s a tabular component we hit the target 50 percent of the time.
These are very good surgeons who do a lot of joint replacement and most these patients still did well but as we’re going forward and trying to look at better and better outcomes we’re going for more narrow targets and we’re trying to customize position of components to the patient instead of trying to make everyone fit a certain mold. And until we can reliably hit that target, we’re not really able to advance forward. So the solutions that have come about are similar to what’s been found in most industry in manufacturing is that employing computers and robotics to improve our accuracy and the reliability of our procedures. So there’s currently numerous options out on the market Mako is certainly the most prevalent and I think there’s like 50 or 60 mega robots here in Florida alone. But Rosa from Zimmer and have you from Smith and Nephew Omni bot from Corrin or all other options that are now within the past year really coming to give some competition to Stryker.
So as I said I am a Mako user so we’ll kind of focus on that. But robotics in general has the same goals. I think the big misconception a lot of my patients have is they’ve all heard about the general surgeons and OBGYNs who are using DaVinci for robotic procedures where there’s a console over in the side of the room the surgeon is not actually physically touching the patient. Mako is different. So I’m still performing the entire surgery the robotic arm just helps guide my hands to make sure that the plan that I decided upon before surgery is the exact plan that’s executed and it will not move without me doing so. The day of me being able to sit in a cot in the lobby with a cup of coffee hasn’t quite gotten here yet.
The process starts well before the patient ever enters the operating room. We get a preoperative C.T. scan which helps us to know what the patient’s anatomy truly is that’s our control. What we saw with computer navigation prior to this robotics is that we were feeding the robot and from that are the computer information. However, the information was an accurate you’d have an accurate result. We then are able to 3D play in the surgery before we ever step foot in the operating room.
Interoperability we confirm anatomical landmarks to the C.T. scan to make sure that we have an accurate plan. And then the robotic arm aligns my hands for the preparation of that acetabular component the hope what we’ve proven is this Does should give us a more accurate component positioning.
It gives me ability to make fine adjustments to the patient interoperability. And there’s been some early studies showing improved outcomes and reduced amounts of dust legacy issues and dislocations. This is performed through any surgical approach. It’s just a tool it’s not a procedure.
So, I do about 60 percent of my hips to an antiwar approach. And there are others through a poster or lateral approach and do them all with make a robot.
Here’s a little example of what it looks like when we’re able to plan the surgery. This is done on a laptop prior to ever setting foot in the operating room. You can scroll through the 3D plan and see what the component looks like or look through a traditional C.T. view. We can change the sizes of the components we can anticipate if the patient had previous hardware or they have a large parish tabular cyst and adjust the components to make our component fit better make our surgery go more smoothly.
So, we’re trying to move from a reactionary standpoint to a predictive standpoint and kind of anticipate any potential problems before we ever step foot in the operating room during surgery, I use a pointer to tell the computer where the anatomy is. Those are the green dots the computer then gives me the blue dots which I have to pop within less than a millimeter of accuracy. And that is how we’ve confirmed that we have the correct plan. The computer knows where the anatomy is and we can go forward with the surgery the robotic arm comes in across the patient. And there are two screens the screen in the bottom right corner is the one the rep uses to run the robot and then I would be looking at the one that’s facing away from us.But it gives us the alignment of the as of tabular component as we’re reading. So we’re reaming in the same exact place that we’re going to put the component to the same exact size. The component that is put in and it’s within a few degrees of the plan post-operative X-Rays are no longer a surprise.
Before this one out of 100 may not look what you thought it would look like. And that really bothered me as a joint surgeon we all tend to be pretty much a perfectionist and you want to know that you’re going to have a perfect outcome when the patient leaves the operating room. So looking back at that study from Harvard 50 percent success rate.
The same study was repeated with the make a robot. And so they were able to put the cup in the correct position 100 percent of the time. This group did do better with their conventional methods of 80 percent success but still 20 percent success. More success putting the component where we want to put it with the robot. So a few case examples these the robot is really made difficult cases much easier and less stressful for me.
This is a 74-year-old male who had had a history of cancer and had radiation to the pelvis. He had developed they’ve actually the necrosis and had lost almost his entire femoral head.
He had a large leg length discrepancy when this patient came into the office, he had gone from being a very active healthy man to being bound to a wheelchair. He was in tremendous pain unable to do any of the activities he previously enjoyed. And with the Mako robot we were able to replicate the leg lengths to get the cup in a great position. I used a couple of screws because of the previous radiation just add a little extra fixation. But this patient within two weeks was transitioning off the Walker back to normal activities. He’s now back to enjoying life. So as a patient who was really on the verge of wasting away in a wheelchair who’s now back in an active member society.
But it can even be used for much more complex cases. So this is a forty five year old male who presented with a severe left hip pain he has a history of hip. Hip dysplasia with a high dislocation of his left hip. There he had had multiple previous procedures as a child but as dysplasia cases do. He now was really limited unable to play with his children. So this is these complex cases that are where it really comes to the importance of preoperative planning. So the C.T. scan gave me a great visualization of what we’re looking at the flat surface at the top is what we call the pseudoacetabulum and that’s where his hip had been articulating for the majority of his life.
But one of the things with dysplasia cases to be successful is I need to get that’s a tabular component back to where his natural assets have him will be to give that couple the chance of lasting for the rest of his life.
Prior to surgery at a long legacy dislocation. But you can see there we’re moving the cup on the proper plane back to the native area of the traditional ice pabulum and it becomes a much easier execution. Extremely happy with the composition and we’ve restored our native hip height. And we were able to do this without an osteotomy. Used a little different stem just because of his extremely small acetabulum.
So moving on to total knee replacements again about a one to two hour surgery. This is we use metal caps to resurface the femur and the tibia. There’s a plastic liner that goes in between plastic or metal bag plastic liner that goes on the back of the patella.
Traditionally we have done this with an intermediate leg guide right in the femur. This was generally then cut the femur was cut at a standard angle introducing a rock guide right into the femoral canal led to increased blood flow and was less accurate. The margin of error of these more traditional instrumentation has been shown to be at least three degrees and when we had a three degree margin of error we had to shoot for a more standardized target to avoid having extreme outliers that would lead to early failure of the implants here’s an example of what some of these instruments look like.
The saw was then used by hand through these small cutting slots and with these implants a lot of times we were kind of cutting the femur in the same way of cutting the bone in the same way every time and then adjusting the ligament its tension to make the knee be balanced and fit well.
So we were in in essence making the patient’s body fit what the implant wanted to be instead of trying to customize the position of the implant to what the patient’s body wanted. Preoperatively we were able to know exactly what size implants we’re going to use we can see how the bone is going to fit or how the implants get to fit the bone how much we’re going to need to take from each area. We registered the bone intraoperatively. these the blue object in those scrub techs hand there with those little reflective disks is how the computer sees what we’re doing that is we use that to point to the bone and confirm these landmarks and then we’re total knee really is a powerful tool is before we make any cuts we can test the ligaments tension that the patients and he has and then adjust the position of the implants within small degrees of acceptable alignment changes to balance those ligaments out without having to go in and release the ligaments the sore then positions itself in air and aligns itself for the cuts. I watch it on the screen to see this all passing through. This is a little bit with that screen looks like the outlines protect the MCL, the latter collateral ligament the PCL, and then also the patella tendon.
So we’re able to we’ve been able to show that this has decreased soft tissue injury decreased complications so we make a very accurate cut because the saw blade is thicker than a normal saw blade and doesn’t have the same tendency to bend when it encounters hard bone and we’ve been able to use this to tackle some really complex cases.
This is a 62-year-old guy who had had this tibia fracture 50 years ago. He worked as a tile his entire life. The fracture he had lived well with. He then suffers another tibial plateau fracture which was fixed in place and failed. And then the patient. Develops severe knee pain. He had no knee pain or no pain from that tibia deformity and then it functioned well his entire life. However, the knee is now causing the problem. He can’t work. So our options when we look at this patient are he has a severe deformity. It would be very difficult to align this which additional tools but to fix that deformity would be a very involved procedure you you usually would use some type of external fixation device with slight correction over time can take a year having pins in the body for a year high chances of infections that can compromise his ability to have a total knee replacement in the future and one of my trauma partners and I talk this over at length about whether that was the best option for this patient but in that time he’s not working for a year he’s living off disability and I think it becomes less and less likely he’ll get back to work.
However due to the robot we’re able to very closely plan this surgery. He had a large defect on the inside of the knee. So we’re having to decide how are we going to compensate for that defect. And here I was able to see that I could actually use a smaller tibial component take out some of that extra bone to help balance the need better and not have to use as much metal you can see that defect. Here there is a flat surface and we’re missing about a third of the tibia. And so when we got interoperability and went to balance his ligaments he had extreme tightness along the medial side.
Which to release completely would probably end up leaving the MCL deficient. And neither would fail we were able to take out this extra bone along that side get the knee well balanced and give this gentleman a knee within an acceptable mechanical access. So he will be able to hopefully use this for many years is still time will tell if this was the right surgery for him but he walked 500 feet the day of surgery the next morning he asked me when he could go back to work.
And so you know I think getting this person back to normal activities will hopefully stand and be the best thing for him in the long run. Not every patient is complex though sometimes it’s a straightforward patient. This is a 52-year-old active male no past medical history. He is very active it a competitive bowler but has developed severe arthritis which limits his ability to do what he enjoys.
This was a more straightforward procedure. We did a relatively standard total knee use this limitless component because a very accurate bone cuts I feel more comfortable doing cementless components which hopefully will translate to a longer lasting implant for this gentleman.
He was done as an outpatient in our hospital. And here he is at his two week visit and really has no limp and he actually went and bowled that night. So. Clearly you know this by adjusting the components to fit his body. He’s had a great outcome. To be fair he would probably have a great outcome no matter what. He is a top notch patient and I think patients have a lot more to do with their outcomes than we do at times. So the robotic platform has only been out for a few years now and so the research is just now catching up. But this is a study out of England.
Guy Ferris Hadad is doing a lot of research on it and they did a study comparing it to their conventionally jig based total knee system and found that these patients were having reduced post-operative pain and decreased pain medication requirements.
They had less blood loss because they weren’t instrumental in the femoral can now. They had return a quad function more quickly were able to use less Petey sessions and had more knee flexion at discharge.
So, it’s an early study but we’re seeing that hopefully using these advanced tools can help us have better outcomes. And so that’s really exactly what we’re hoping better outcomes less pain faster return activity fewer complications having a more accurately placed implant that will last longer. And in the end what we all care about is just having happier patient. Thank you.