Advance with MUSC Health

Robotic-Assisted Joint Replacement Surgery

May 20, 2022
Eric Hansen M.D.

Robots are assisting MUSC Health surgeons to offer more personalized and precise procedures that can lead to a quicker recovery. Erik Hansen, M.D., an orthopedic surgeon specializing in adult reconstructive surgery, talks about how robotic-assisted joint replacement surgery is being used at MUSC Health and the benefits of this technology.

“[Some] patients develop arthritis or other debilitating conditions that involve their joints and it's affecting their quality of life. To be able to go in there and replace the joints and give them a new functioning joint, that lets them get back to the things that they want to do and be able to enjoy their life, is a remarkable and powerful procedure.”


- Erik Hansen, M.D.

Topics covered in this show

  • Arthritis is a debilitating condition and having surgery can improve quality of life for 20 to 30 years after the surgery.

  • There are two options for surgery that can be discussed with a surgeon. One is partial replacement, which is when the surgeon takes the arthritis out from one specific area. Second is a full replacement, which may require the surgeon to adjust other ligaments, but is necessary in some cases.


  • MUSC Health is using the CORI robot, which is a 3D-screening tool that allows surgeons to see the whole joint on a screen, and then the surgery itself is hands-on and controlled by the surgeon. The robot helps the surgeon get the implants in the perfect position by mapping out the join on the screen and allows the surgeon to size the implant accurately and then put them into a position that's specific for that patient.

  • Robotic-assisted surgery helps with quicker recovery. Patients are up walking within several hours of surgery, and about half of the patients go home the same day. The other half stay overnight, but all surgeries include outpatient therapy to improve function and recovery.

  • Research has shown that being on opiate medication prior to surgery leads to worse outcomes after surgery. Because the body is already used to the medication, it doesn’t provide the same pain relief post-surgery to the patient. These patients tend to have more pain after surgery and recover at a slower pace. There is an effort to wean patients from narcotic pain medication prior to surgery to improve outcomes and quality of life.
  • Mental health is another important part of post-surgery outcomes. Because everyone perceives pain differently, one important indicator of positive post-surgery outcomes in good mental health treatments prior to surgery.

  • MUSC Health provides pre-surgery education through a preoperative clinic. This clinic offers a class on joint replacements to provide important information and improve a patient’s experience post-surgery.


  • Using robotics expands what surgeons can provide to their patients including better quality of life and better outcomes. As the technology improves, MUSC Health will introduce the most advanced technology to improve their patients’ lives.

Read the show transcript below

Erin Spain [00:00:04] Welcome to Advance with MUSC Health. I'm your host, Erin Spain. This show's mission is to help you find ways to preserve and optimize your health and get the care you need to live well. Robots are assisting MUSC health surgeons on many different parts of the body to offer more personalized and precise procedures that can lead to a quicker recovery. Dr. Erik Hansen, an orthopedic surgeon specializing in adult reconstructive surgery, joins me to talk about how robotic assistant joint replacement surgery is being used at MUSC Health and the benefits of this technology. Welcome to the show, Dr. Hansen.

Erik Hansen [00:00:47] Thank you for having me.

Erin Spain [00:00:48] Tell me about joint replacement surgeries and what joints do you work on? Which are the most common types of surgeries as well?

Erik Hansen [00:00:55] Sure. I'm primarily a hip and knee surgeon, which are probably the two most common joints that people have replaced. There are other joints that people have replaced, but by far the hip and knee are the two most common. In overall hip replacement surgeries, very successful surgery. As far as patients develop arthritis or other debilitating conditions that involve their joints and it's affecting their quality of life to be able to go in there and replace the joints and give them a new functioning joint that lets them get back to the things that they want to do and be able to enjoy their life is a really remarkable and powerful procedure. We take care of not only the simple cases, but also the most complex cases. So we have significant skill and familiarity with the whole array of complexity when it comes to replacements.

Erin Spain [00:01:41] Tell me about a typical patient. You mentioned arthritis. Maybe these are some older folks.

Erik Hansen [00:01:46] Yeah, the majority of our patients are older. They have degeneration of that cartilage in their joints that leads to pain and loss of function. But there are other reasons we do it, too. If there's injury to the bone, from disruption of the blood flow to the bone and that bone is no longer longer healthy, or patients who have inflammatory conditions like rheumatoid arthritis or lupus, and that inflammation causes the degeneration of their cartilage. Those patients also could benefit from this type of operation.

Erin Spain [00:02:12] You said you do these procedures quite a bit. They're very common.

Erik Hansen [00:02:15] Oh, yeah.

Erin Spain [00:02:16] Can these surgeries be complex?

Erik Hansen [00:02:18] For sure. No two patients are the same. Every patient has their unique qualities about their joints, and which is why I think robotics can be helpful to be able to really personalize the surgery. And the more information you can have, which is one of the benefits of robotics, it gives you more information to be able to then do a more accurate and precise surgery, helps reduce the complexity to some degree, and makes the surgery a little bit easier. But there are definitely varying levels of complexity when it comes to joint replacement surgery.

Erin Spain [00:02:48] Explain how you use a robot here at MUSC Health called the CORI robot. The benefits of this technology you already mentioned, it kind of helps you map out the person's anatomy before you even get into surgery.

Erik Hansen [00:03:02] It's an image list system, which is nice. So there's some robots that require CT scans and things before surgery, and this one doesn't. This one, when we get to the operating room, we open up the knee, we essentially map out the knee, create a 3D model on the robot, which then allows us to compare that anatomy to a database of millions of CT scans and MRIs that have been uploaded to this database to then create this model, which then lets us be able to size the implants accurately and then put them into a position that's specific for that patient. We stress the knee, we get range of motion information and ligament stability information that then lets us precisely put the implant in to millimeters of accuracy.

Erin Spain [00:03:46] What does the CORI robot look like? How do you use it? What's it like to use it?

Erik Hansen [00:03:51] It's really not that big of a robot and I think robot somewhat of a misnomer. It's not truly like a robot, if anything. It's a screen that has information that we can then manipulate or change with a handheld instrument or a bird that then the surgeon can then use to perform the surgery. So it's not a robot where this robot is doing the whole surgery and that the surgeon is in the corner of the room kind of manipulating things over there. The surgeon is still doing the surgery and so we're still hands on operation.

Erin Spain [00:04:23] For patients the experience probably isn't that different. I mean, they're coming and they're doing a consultation, but what's going on behind the scenes that could enhance the experience because you're using robotic assisted surgery?

Erik Hansen [00:04:34] I think there's ability for more information for the patient or following these patients out and seeing how they do following the robotic surgery. And in my experience, they seem to be recovering quicker than doing the manual surgery. I think the ability for us to then put the implants in specifically for that patient is allowing them to recover quicker. And I think that will bear out in the data that we're collecting for this. But overall, for the patient's experience is really not a whole lot different. When they come in, they see me in clinic. I sign them up for surgery. There's no additional pre work that they need before having surgery for the robot specifically. And then they have the surgery. They go home after surgery. There's really no difference. Besides, with the goal of having a quicker recovery.

Erin Spain [00:05:17] You mentioned the 3D modeling that takes place as soon as you get into the O.R. How is this for you as a surgeon? Just elaborate on that a bit more about how this technology really is a game changer.

Erik Hansen [00:05:30] Sure. In my position as a professor and an educator here, I think it helps twofold. It helps. One, with me, I like having as much information as I can when I'm doing the surgery. Our classic way of doing a knee replacement surgery is kind of a one size fits all type technique where we make our bony cuts kind of similar to every patient to some extent. And this 3D model gives us an ability to really analyze the anatomy of that patient's bone and how their deformity is and how we can correct it. It just gives us a lot more information. And then from a teaching standpoint, it allows me to show the resident and be like, when we change the implant position this way, this is what happens. And so it gives us a visual and objective information about how we're putting the implant in.

Erin Spain [00:06:20] Tell me about the typical recovery for patients who have these types of joint replacement surgeries.

Erik Hansen [00:06:25] We get the patient up walking within a several hours of surgery. About half of the patients go home the same day. The other half stay overnight. And we're doing more and more outpatient therapy. Classically, patients will stay in the hospital for a couple of days and go home and have a therapist out their house for several weeks and then they get into outpatient therapy. But we're really trying to accelerate the recovery. I'm getting patients up and walking, get them home and then getting them into outpatient physical therapy where they can really work on their motion, the strengthening and getting them back to doing those activities that they wanted to do earlier.

Erin Spain [00:06:57] So how can somebody know when it's time to come see an orthopedic surgeon? Tell me about the symptoms that lead up to this.

Erik Hansen [00:07:05] Sure. A lot of it is pain related and stiffness when it comes down to especially knee arthritis. I mean, hip arthritis similarly. But a lot of it is pain and trying those things like modifying our activities, taking medications. And when you can't do the things you want to do, that's the time to come and see and get an X-ray and kind of see what's going on. There's different things that we can do as far as like injections and things to improve the symptoms. But when those conservative things don't no longer work, then that's the time to have that discussion about if surgery is the next step.

Erin Spain [00:07:37] Well, and you're particularly interested in this pain aspect and how pain is controlled with joint issues and you've actually published some research about this. Tell me about your research that you've published with opioid use and joint repair and replacement surgery and also mental health.

Erik Hansen [00:07:54] We were looking at the reasons why patients that we think should be able to go home the same day of surgery don't and some of those different things or the reasons why is being on narcotic pain medication prior to surgery. And that's one of those things that we know from a lot of different data that being on opiate medication prior to surgery leads to worse outcomes after surgery. Part of the reason of that is because you're already on the medication that we're going to put you on after surgery. And so your body's already used to that medication. So if we are then trying to give you more medication, you don't respond to it as well. And those patients tend to have more pain after surgery, recover at a slower pace. And so trying to get patients off of narcotic pain medication prior to surgery is something that we strive to do to improve outcomes. And then mental health is another big component of pain. There's a lot of different ways of reasons why people have pain and how they perceive pain. And that's one of the things that another factor in that algorithm. And so having good mental health treatments prior to surgery helps improve the recovery after surgery. And then also after surgery, we try to control pain in multiple different ways. We have a multimodal pain protocol. Instead of just treating patients with opiate medication after surgery, putting them on an anti-inflammatory, putting them on a nerve pain related medication to try to control pain in different ways because there's a lot of different factors that go into how people perceive pain.

Erin Spain [00:09:21] So given this information, there is quite a bit of pre-work that can go into surgery. Tell me about the ideal situation. How long does it take from when a person comes from consultation to when they get to leave the hospital and then some of these maybe longer cases or people are working through getting off of a certain drug?

Erik Hansen [00:09:40] One of the ways that we strive for good outcomes after surgery is getting patients optimized prior to surgery. So there's various amounts of time that are required to get a patient ready for surgery. And so that can be quite variable. You know, ideally at the perfect scenario, a patient comes in, they see me in clinic and then they have surgery up to a month later. We have an excellent preoperative clinic here, which all of our patients go through where they see a medicine provider and they to make sure from a medical standpoint that they're optimized, they see anesthesia and they have the joint replacements class and everything at that point to make sure that everyone understands the expectations, that everyone is good for surgery so that we try to prevent those complications from occurring down the road.

Erin Spain [00:10:21] So you've had the opportunity to really get it on the ground floor of some of this robotic surgery like the CORI Robot. What do you see for the future? Can you see this technology improving even more?

Erik Hansen [00:10:33] I think it's going to continue to expand. We're primarily doing it now. We're initial, as we say, primary knee replacement. So we're going in and we're taking the arthritis out, we're putting a knee replacement in. But sometimes we have to do surgery where it which is a big part of our practice, where we're taking a knee replacement out and putting a new one in revision knee replacement surgery. And that's an even more complex surgery. So to be able to use robotics and that additional information we get from robotics I think is the next step up in that spectrum is to be able to expand that. And then we get into, you know, right now we're primarily doing knee replacements robotically here. And then in the coming months, I'm going to be doing some hip replacements robotically. And so I think that the indications will be continuing to expand as technology improves. We'll continue to expand the uses with our joint replacement patients as well.

Erin Spain [00:11:22] That brings up a good point. How long do these replacements typically last and how often do you have to do revisions in a lifetime?

Erik Hansen [00:11:30] The goal is to get 20 to 30 years out. I think there's plenty of data that that these joint replacements should be lasting that long, but sometimes they don't for a lot of different reasons why they don't. But the goal is anytime we put them in until at least 20 to 30 years.

Erin Spain [00:11:43] Is it a pretty good mix of men and women that you see coming through as patients?

Erik Hansen [00:11:47]  It's probably 50-50 would be men and women that we see. Women can have earlier arthritis if they have hip dysplasia. That tends to be something that we see more commonly in females and younger females, more so than males.

Erin Spain [00:11:59] Are there different considerations with the different genders when it comes to doing these surgeries?

Erik Hansen [00:12:04] No, not really. You know, when it comes to knee replacements, one of the advantages or one of the things we can do in knee replacements that I do quite frequently is partial knee replacements, which I think is a very one of the main reasons I use robotics actually is partial knee replacements, because in those surgeries, the implant position is very, very important. And that's what the robot helps us do, is get the implants in the perfect position. But for younger patients who want to stay active and partial knee replacement's a very good surgery. If you have arthritis and only one area of the knee, we're able to go in and just take the arthritis out from that one specific area and we leave all your knee ligaments alone in which we do a total knee replacement. We have to take out the ACL, sometimes the PCL. And so some of those biomechanics then have to be done through the implant. While in a partial knee replacement, it feels a little bit more normal because all of your ligaments, we leave all your ligaments alone. And so that's another advantage, especially for the younger patient who has arthritis is another option for them.

Erin Spain [00:12:55] Tell me about some of these results and how life changing this can be for your patients after they've had this surgery, they've done the rehab and they're back out in the world doing what they loved to do.

Erik Hansen [00:13:05] Arthritis can be a really debilitating condition. It can really affect your quality of life to the point where you can't really walk. And so I've had patients who come in, who are on a walk, are only able to walk very short distances, and then you replace their joints, and now they're able to walk without any assisted device. And it's a night and day difference. The outcomes and how you can affect somebody's life is pretty dramatic.

Erin Spain [00:13:27] What do you do to optimize your health and live well?

Erik Hansen [00:13:30] Sure. I try to exercise regularly, at least a couple of times a week when I can and then try to eat a balanced diet. I think a lot of that I thank my wife for, but just trying to live a healthy lifestyle is trying to stay active, not smoking. Being as active as I can be.

Erin Spain [00:13:46] I bet some of these patients inspire you, too.

Erik Hansen [00:13:48] Some of them they want to get back to doing for after their surgeries. It's pretty remarkable. They will me to be more active when I see how active they are.

Erin Spain [00:13:58] For more information on this podcast, check out Advance dot MUSC Health dot org.