Michael Smith, MD (Host): This is Southwest General Health Talk. I'm Dr. Mike. And with me today is Dr. Daniel Karns, an orthopedic surgeon with Southwest General Health Center. And we're going to be talking about knee and hip replacements today, who needs them, what surgery and recovery really looks like, and how these procedures can help people get back to an active life. Dr. Karns, welcome to the show.

Daniel Karns, MD: Hello. Great to be here.

Host: Thank you. Let's start off with what are the most common reasons a patient may need a hip or knee replacement?

Daniel Karns, MD: So, the most common reason is the advancement of arthritis, which is the protective layer in the joint that wears away. And so when that layer wears away enough, pain progresses and deformity and function.

Host: And what, like, age range do you normally see this occur at?

Daniel Karns, MD: So, it's interesting. I've been in practice for 33 years, and we see this in all age ranges, including, you know, people as young as their 40s. And years ago, when I first started practice, we didn't do knee replacements on people under 60, and it has slowly progressed that we do it in younger and younger people because it's a great option, and the technology has gotten better over the years.

Host: Before you determine whether somebody is a good candidate for knee or hip replacement, what kind of workup do you go through with the patient? Like, what makes you help determine whether they could do surgery or not?

Daniel Karns, MD: Sure. So typically, when I see a patient, the first step is speaking to the patient, finding out what the problem is, how it affects their life on a regular basis. I examine the patients. X-rays are an important part of the diagnostic part of this. And typically, X-rays alone can tell us the degree of arthritis that a patient has in that joint. So, that's the initial assessment.

Host: When you're with a patient and you're in the middle of making kind of this decision, they do look like they're a good candidate for surgery, is that it? Are you just rushed off and you go right to surgery? Or is there a time period of maybe you do try exercise, medication? How does that process work?

Daniel Karns, MD: So certainly, the first time I meet a patient, I never say, "Let's do a hip or knee replacement." There are certain conservative treatments that can be done that can be beneficial and maybe put off a hip or knee replacement. So, physical therapy, cortisone injections, sometimes braces can be helpful. Sometimes anti-inflammatories taken orally, Advil or Motrin. So, there's a whole gamut of things that can be done before we rush to do a surgery.

Host: One of the things I remember years ago when I was in medical school, you know, doing my rotations and everything, a lot of the surgeons back then would often wait to do surgery almost to the point where the person simply could not go through a normal day, right? Is that the case still, or are we more prone to go to surgery a little bit earlier when the person's a little younger and maybe recovery's maybe a little bit better?

Daniel Karns, MD: So, we talk about quality of life. I talk about that with all my patients, and that affects everyone individually. And if lifestyle is affected, where they can't walk and do grocery shopping, where they can't participate in some element of exercises, then we're more apt to do something if the conservative measures have failed, such as injections, therapy, braces, and things like that. So, there's no doubt that we do it sooner than we have in the past, because no one wants to live in misery for an extended period of time.

Host: Now, you said you've been doing this how many years now, 30 years or so?

Daniel Karns, MD: Thirty-three years in practice. Yep.

Host: Thirty-three years. So, you've seen probably a lot of changes in just the surgeries themselves. Tell us a little bit about what you've experienced from when you started and to what you see today.

Daniel Karns, MD: If nothing else, materials that we use now have longer-lasting properties. So whether it's the metal, whether it's the cement, things like that, that's a big issue in terms of why we're doing it sooner. The recovery and the post-op course has changed significantly. When I first started, people were in bed for two days in a machine that bent the knee, not even getting out of bed. Now, our patients, whether it's a hip or knee replacement, they're out of bed within two hours with physical therapy, getting up and standing and walking.

Host: And that's made a big difference, right? Getting people up and moving quickly, right?

Daniel Karns, MD: And people go home sooner. Instead of two weeks, instead of one week, instead of five days, instead of three days, now people are going home the same day or the next day. And that has made a huge difference, because I think people do much better when they're in their home environment. Sometimes they're doing outpatient therapy, sometimes they're doing home therapy where someone comes out to their house and works with them.

Host: Speaking about like how surgery is today, you know, we're hearing a lot more about robotics, AI, all that kind of stuff. How is that affecting what you do?

Daniel Karns, MD: So, I don't think AI is in the operating room yet that I know of. We use it in the office setting. So, it is helpful from that standpoint. There are robotics that can be used in doing knee and hip surgery. I've been to courses. There are some studies that say that the ultimate outcomes are pretty equal, whether a robot is used or not used The idea is that it gets it in the perfect ideal position. That's the kind of the idea behind a robot, but it still takes a surgeon's hands behind the robot to execute what needs to be done.

Host: And you mentioned before, probably one of the greatest advances is simply the material that you're using, right? That's really allowed these artificial limbs to last a lot longer. Can you tell us a little bit more about that material and why that's lasting longer?

Daniel Karns, MD: We're using a combination of cobalt-chrome, stainless steel, titanium, high-density plastics that have less wear over time than they did 25, 30 years ago. So if a joint replacement lasted ten to fifteen years, 30-plus years ago, we now in the lab have simulated some of these joints to last 30-plus years. And the cement techniques and the cement that we're using, which is part of the whole process, works better than it did previously.

Host: Can you walk us through, if I was a patient of yours and we're about to go into surgery, what would you tell me? What can I expect a little bit before, a little after, and what is my recovery going to look like?

Daniel Karns, MD: With knee replacement specifically, most patients get a nerve block. So the anesthesiologist will perform a novocaine-type block, typically in the groin that provides some postoperative pain relief. That's also done for some hip replacements too. And so, that's become the anesthesiologist expertise in terms of the location of where that block is done. And that can provide anywhere from 12 to 24 hours of some additional pain relief in addition to the narcotics or anti-inflammatories that we're giving people. So, that's done before you get into the operating room itself. Once the patient goes to the operating room, and then they are either put to sleep with a general anesthetic or have surgery under a spinal anesthetic, there are some advantages and disadvantages of both methods. And that's done pretty much according to what the anesthesiologist prefers from that standpoint. So, that's the basic preparation in the hospital right before surgery.

Host: Let me ask you. So, given the option of general anesthesia versus spinal, what do you prefer as a surgeon? And, I guess, can you go into the advantage of the spinal a little bit more?

Daniel Karns, MD: Well, I think that some of the advantages of the spinal is that you're not getting a full general anesthetic in terms of whatever that does to affect your mental status, your physical status afterwards. They still get a twilight medicine. So, the patient doesn't really know what's going on. They're still out of it from that standpoint. They can't participate in our drills and hammers as we're doing our hard work in the operating room. From my standpoint, as long as I can do the procedure and the patient obviously is comfortable, then I don't have a preference in terms of which one is done.

Host: Now, between knee and hip, you've touched on this, hip replacement is going to have a longer recovery. Is that true?

Daniel Karns, MD: Well, in general, I tell people the recovery is pretty much the same regardless of whether it's a knee or hip. In the initial recovery, my patients are on a walker or a cane, you know, from two to six weeks roughly. A lot of patients come to my office on a cane at two weeks. Some people are on a walker for a month. From a knee and hip recovery standpoint, there's more intense physical therapy for a knee replacement because we're really working on gaining range of motion and things like that, whereas the hip is a little bit easier. We're not working on just getting around and working some of the muscles. So, the hip in some ways has a little bit of an easier recovery, but there's still the timeframe of four to six weeks. I tell my patients four to six weeks to feel decent, and it can take up to four to six months to really recover, and that's an active recovery process where they are literally up within two hours of surgery. And they're doing all the hard work right from the beginning.

Host: And that obviously includes physical therapy right off the bat.

Daniel Karns, MD: Yes. Physical therapy right off the bat, and that's the mainstay of the whole recovery. My part, I tell my patients, is the easy part. Mine takes an hour or so to do, and they have the hard part over the next, you know, three months in terms of doing all the hard work.

Host: But that activity, would you, I guess, agree that that's critical, right? To keep that joint moving.

Daniel Karns, MD: It's critical to the recovery and the overall outcome. And if the patient is not doing their part of therapy, they're not going to get the best result.

Host: What do you see in your experience? Are most people engaged in this? I mean, they start to feel better, I would have to assume, down the line. So, they stick with the physical therapy. Or do a lot of people just, it hurts and they just can't do it?

Daniel Karns, MD: Well, I think that's probably a small percent of patients who really don't participate for whatever reason. And that being partly the nature of the patient. So, part of my job is to counsel people before surgery and warn them, "This is going to hurt initially. The first two weeks are going to be rough. You got to work through it, and you are going to get better." And I think that, patient expectations really has a big part in the role of the recovery. You tell them it's going to be a breeze from the beginning and it isn't, you know, then they're going to sit back and do nothing. So, part of my job is to give people realistic expectations.

Host: So, what can patients realistically expect to be able to do after a knee or hip rep- replacement?

Daniel Karns, MD: The normal activities, I tell people non-pounding activities, which includes golfing, biking, swimming, gentle hiking, walking unlimited. There are recent studies that show pickleball and maybe some other racket sports don't have as big a detrimental effect on the joint replacement as we had thought previously, meaning that the pounding of some of these sports can reduce the longevity of the prosthesis. I don't recommend anyone to jog and run as a form of exercise or to play basketball. But the pickleball, tennis activity where if you're playing doubles and you're covering a smaller amount of territory, that may be realistic in the recovery.

Host: Is there any last word you have for the audience who, you know, maybe somebody is having to decide between surgery for a hip or knee replacement? Any last words you'd like to give to that person?

Daniel Karns, MD: Well, it's not uncommon that I hear my patients, you know, when they've recovered three months down the road, they say, "Wow, I wish I had done it sooner." I hear that very commonly where, you know, people are nervous about taking that step. But once they've gone through, and I see patients, you know, six weeks post-op, three months post-op, I see them a year and two years after surgery. And it's not unusual people come back a year later and say, "Wow, it feels like I didn't have anything done, and I feel great."

Now, I also warn people, nothing is a hundred percent, you know. And there are a small percent of patients who have some persistent pain despite going through therapy and doing their effort.

So, I don't want to give anyone the misnomer that, you know, you do a knee replacement and, boom, you're just a hundred percent back to normal. It takes everyone's hard work to really accomplish that.

Host: Dr. Karns, this has been fantastic. I want to thank you for coming on today. I know the information will help a lot of people. To request an appointment with Dr. Karns, you can visit swgeneral.com. If you found this episode to be helpful, consider sharing it and check out our full library for topics of interest to you. This has been another episode of Southwest General Health Talk. Thanks for listening.