Transcription:
The Swollen Knee

Scott Webb (Host): Though having a swollen knee is fairly common. Did you know that gout or Lyme disease may be the cause? I didn't either, but that's why we have on experts, like my guest today. I'm joined again by Dr. Barry Hyman. He's an Orthopedic Surgeon with Montefiore St. Luke's Cornwall. And he's here this time to talk about all the causes and treatment options for swollen knees.

This is Doc Talk presented by Montefiore St. Luke's Cornwall. I'm Scott Webb. Dr. Hyman it is so great to have you back on. Last time, we talked about common knee pain, knee injuries, treatment options, and so on. And today we're going to talk about the swollen knee and I, you know, back in the day, I think we used to refer to a swollen knee is having water on the knee. But I think effusion is probably the better medical term today. So, how do people end up with an effusion?

Barry Hyman, MD (Guest): So, that's a common thing that I see in my practice. Somebody comes in with a knee that's quite swollen and painful, and there are many reasons why that can happen. And obviously in my position as an Orthopedic Surgeon, I have to try to figure out what is the reason. So, first thing as we all start, we start with the history to find out has this been going on for a while? Is this the first time? And then you can ask a little bit about family history. For instance, one of the common causes of knee swelling, obviously there could be trauma, but there are non traumatic causes and gout is a common cause, where people have too much uric acid in their body. And they create crystals and that forces fluid inside the knee. And so one of the questions you ask in your history is have you ever had gout before or have anyone in your family have gout? And a lot of people know gout is a big toe problem with swelling and pain, but it can also occur with the knee.

So, you would start by asking the patient the history and you would get that, but there's some condition called pseudogout, pseudogout, pseudo in Latin means like gout and in medicine, we like to use Latin words to make us sound important. But it's like gout because there's calcium crystals in the knee instead of uric acid crystals in the knee.

And that can also form fluid, push fluid into the knee joint. And some people, you can see it by getting an x-ray. If you look at an x-ray, you can sort of sometimes see calcification along the meniscus. And you know, that's probably the reason why the person has a swollen knee. But sometimes you don't see it on an x-ray and the best way to find out between gout and pseudogout is you actually take the fluid out and send it to the lab. And they look at it under a microscope. It's called a polarized microscope, when the crystals go one way it's gout and the other way, it's a pseudogout. And so, those are two very common causes of knee swelling that I see. But there are many others.

Host: Yeah, I'm sure there are. And I was going to ask you what are the signs and symptoms, but I, I sort of thought to myself, well, obviously if your knee is swollen, that's a pretty good sign or symptom. So, maybe, I want to rephrase that question as, when is the swelling too much swelling? Like when we look at our two knees and one is bigger than the other, when is it swollen enough that we should reach out to our primary or get a referral?

Dr. Hyman: Well, one is when you have trouble walking or you can't walk with a normal gait, you're walking with a limp. If you can't extend your knee all the way or when there's a lot of pain, when you move your knee. I live in the New York area and one of the common things that I see at my office as an Orthopedist is a swollen knee, secondary to Lyme disease.

And that's something that a lot of people might not think of. But that's because Lyme presents in so many different ways. In a medical doctor's office, somebody may be tired and exhausted or have multiple joint problems, but for me as a knee specialist, when people come in, that may be their first symptom, a swollen knee, and I've diagnosed as many, many cases of people who've had Lyme as that, that was the reason why the knee is swollen. So, you have to think of that. That's usually just a blood test. But you want to rule out the other causes of swelling. So, sometimes I'll take the fluid out of the knee, check it for crystals. There's no crystals there. And then I'll do the blood test for Lyme.

But are you going to ask, also ask questions? Do they have a dog at home that they take out? Do they go do gardening? Are they in the woods? If they have none of those, it's unlikely that they have, Lyme. But, that is a common cause of knee swelling that we see.

Another cause is a bleed in the knee. We, we again use a fancy Latin word. You can say hemarthrosis bleed into the knee joint. Arthrosis is a joint. And that could be either trauma. Somebody could have some trauma or it could be spontaneous. So, another question to ask, are you on blood thinners? Or you've been taking aspirin or an anti-inflammatory cause somebody can have a minor trauma, be on aspirin or on blood thinners, and then you can bleed into the knee also.

Now, when you bleed into the knee again, once you got the history, when you take the fluid out of the knee, you can have a different color. So, it could be a yellowish fluid that could be the gout or pseudogout, or sometimes gout and pseudogout, are a little more whiteish yellow. It could be blood. Then they've got the hemarthrosis and blood could be again from taking blood thinners or some people can injure their knee, like an ACL injury, which often will cause some bleeding and you can have some trauma and that can cause that, and then rarely though you can have an infection in the knee and then that you take it out and it'd be pus. But the exam of an infection of a knee is so different than the exam for everything else I mentioned. Although everybody has pain when they move their knee for the others, when you have an infection, the pain gets really severe and it's really incredibly severe, even just for a little motion. But again, you can often tell by just removing the fluid. Now we don't remove fluid on every single person who has a swollen knee. So, some people who are needle-phobic, don't have to worry that if they're going to go to the doctor, they're going to stick a needle in, that doesn't always happen. A lot of times, if it's trauma, for instance, we can get an MRI and that'll tell us what's going on. So, it really depends on the history is so important. The exam is very important. Those things are really important to determine what to do for somebody with the problem.

Host: This is really interesting, really educational. Things that I have not heard before, gout, Lyme disease as causes of a swollen knee. So, I'm so glad to have you on and be able to pick your brain a little bit. I'm sure listeners are enjoying this as well. So, besides you, you know, you mentioned taking the fluid out, obviously you have a swollen knee, which is full of fluid, so let's take the fluid out and then we can look at it and figure out what's going on. What other treatment options are available to folks who have a swollen knee?

Dr. Hyman: The treatment is sometimes real simple. If I suspect there's gout or pseudogout, while I take that needle or the fluid out in the same needle, I can throw some cortisone in without an extra stick or anything, and that often will solve the problem. By the time we get the results from the lab, the patient's already feeling better. That's one treatment for that. Obviously, if you get blood, you know, not to put cortisone in, cause it's a different problem. But just taking blood out sometimes helps with the pain, especially if somebody has it for trauma and then you may send them for the MRI to find out more specifically, if there's no fracture that shows up on an x-ray.

Host: Yeah, I was just taking all this in and I'm thinking to myself, you know, a lot of folks probably live with things, right. Even though things like a swollen knee, it might be affecting our quality of life. A lot of us have trouble reaching out to our doctors or finding the time and then getting a referral and so on. But I'm guessing there are some complications if a swollen knee goes untreated.

Dr. Hyman: Absolutely. It's not normal to walk with a swollen knee. And, you can throw out your back cause you're walking with a limp, and sometimes it's so easily treated, though sometimes it's a little more complex. I mean, one of the causes of knee swelling that we didn't mention are auto-immune, your body's own system fights against that. People who could have rheumatoid arthritis, lupus, there are other causes of an auto immune response and that's treatable also though, you don't have to live with that.

You find out what it is. You do a blood test that shows that you have something like that. And there are great doctors who can help treat these things. So, a swollen knee is very treatable. And why walk around with a swollen knee when it can be treated?

Host: Yeah, that makes perfect sense to me. Why do that if we don't have to? And in so many things that most of us drag our feet on and go into the doctor, but in hearing you today and talking about how relatively easy it is to diagnose and to treat, every good reason to reach out to an orthopedist or yourself.

And as we wrap up here, and you mentioned earlier about family history, when it comes to swollen knees, so I'm sure folks would be left wondering, well, what can we do to prevent having a swollen knee? You know, knowing our family history would be good, avoiding things, the triggers or risk factors, things like that, but I'll leave it to you in your words. What is there anything we can do to prevent an effusion?

Dr. Hyman: The answer is if you as a person who knows why you have it, like, if you're a person who has gout to your knees, it's diet, there's certain things that you shouldn't be taking. Red meats, cheeses. And, so maybe a little too much beer. But there are certain things that you can do to avoid that if you know that that's the cause of it.

If you're on blood thinners, obviously you've got to be a little more careful with yourself and not let yourself collide into things. Other than that, it's like anything else? If you exercise and take care of your body, there's a less of a chance that you can have an episode with some sort of trauma.

A couple of times, people can pull a muscle or tear a muscle, and that can cause a problem. By exercising, you can prevent that. Swollen knees are a little harder to, to prevent unless it's something like gout that, you know, what you can do to prevent it. But often they are treatable.

And once you find out what's the cause of it, then, for instance, if it's from a autoimmune disorder, this is what are you treat the autoimmune disorder. And so, if it's from Lyme, you treat the Lyme. So, often it's treatable. And then once it's treated, especially with Lyme, which is just a course of antibiotics for maybe three or four weeks, and you're finished with it. And you don't have the problems later on. It's really worthwhile going ahead and getting yourself treated. Prevention's a little harder.

Host: Yeah, I hear what you're saying. And as I said, this has been really educational between gout and Lyme disease, I have learned so much. I've really enjoyed these conversations that we've had. So, thank you so much and you stay well.

Dr. Hyman: Thank you very much.

Host: And visit montefiore.slc.org for more information. And if you found this podcast to be helpful, please be sure to share it on your social channels and be sure to check out all the other Doc Talk episodes. This has been Doc Talk, the podcast from Montefiore St. Luke's Cornwall Hospital. I'm Scott Webb. Stay well.