Transcription:

Melanie Cole (Host): . Welcome to Right Beside You, a Reid Health podcast. I'm Melanie Cole and today, we're exploring cartilage restoration techniques for focal cartilage damage. If you don't know what that is, you're going to find out on this podcast. Joining me is Dr. James T. Redshaw. He's an Orthopedic Sports Surgeon with Reid Health. Dr. Redshaw, thank you so much for being with us. Before we get into this, I'd like you to give us a little physiology lesson. Tell us what articular cartilage is and how it differs from say meniscus, things people have heard of.

James T. Redshaw, MD (Guest): Hey, nice to be here. Thanks for having me. Focal cartilage defects are localized, usually contained injuries to the articular cartilage of the knee, whether it's the end of the femur or the top of the tibia. The articular cartilage in your knee is the smoothest surface in your body, it's meant to articulate. It's a thousand times smoother than ice on ice.

And so injury to those areas can cause a lot of discomfort, mostly by affecting the surrounding structures, whether that's the menisci or the bone, as well as cost mechanical issues, whether it's clicking, catching, or just unpleasant sensations in the knee. This is a little bit in contrast to what other providers might deal with in terms of larger global cartilage loss, which is commonly referred to as osteoarthritis that a lot of people might be familiar with.

Osteoarthritis tends to affect large kind of diffuse global areas of joints. Whereas these focal cartilage defects that we're talking about today, are usually the result of kind of an injury. And they're very specific in one location and a much different problem to deal with. Things like your meniscus can be thought of this shock absorbers in your knee, which many people have heard of, they help protect this cartilage because of how valuable it is.

But injury to things like other structures in the knee, such as your menisci, such as your ACL and other ligaments can all have negative impacts on this cartilage. And so a lot of the times people will undergo surgeries on certain ligaments and structures in their knee or other joints merely to protect this cartilage. And so it's very, very valuable, especially as people want to live active lifestyles, that their joints are moving properly and that they can avoid osteoarthritis or that global breakdown of cartilage for as long as possible throughout their lives.

Host: Excellent explanation. It really does allow the bones to glide over each other with very little friction. So, how is it damaged? What are the most common causes of injury to this area?

Dr. Redshaw: The most common injuries that would result in kind of a focal defect of the cartilage in the knee, it's usually a traumatic injury. You can get it from a direct blow to the area. It's usually a little bit more higher impact. So, we'll see these things with anywhere from certain falls from height, maybe falls while even on your feet with a direct impact to the joint. You can see this in automobile accidents. You can see it in even high level collisions with sporting events, certain times certain twisting injuries even, can cause a shear type injury to the cartilage where a flap of cartilage might be affected. And those are a little bit more common just because they require less energy than the other high energy injuries that we're speaking of.

But usually it's an event that people can kind of remember or recall, and they know that their knee was okay before that event. And then after, something was drastically different. This is kind of different than osteoarthritis in terms of that's more of a general wear and tear. And it takes place over time, months, years usually in the making. A lot of the times we think of it as kind of the tread on your tires. If you were to pop a flat in your tire and need to get it patched, that's more of a focal defect of the cartilage. Whereas if your treads on your tires just wear down over time, because it's been several years or it's been through so many miles, that's more of a picture of osteoarthritis.

Host: Well, so tell us a little bit about articular cartilage. Will it regenerate? Does it, it has poor healing qualities, right? So, will these kinds of injuries, sometimes people get a tear or they get, you know, something and they're wondering if this will regenerate or heal itself or does that kind of an injury lead to further deterioration over time?

Dr. Redshaw: That's a great point. The problem with the articular cartilage injuries is, is that the number one, the articular cartilage is so important. And two, it has very poor ability to heal on its own. Once people reach maturity, you know, adult age, the articular cartilage actually has a very poor blood supply and thus poor ability to regenerate or heal itself. Most of it's nutrients actually come from the diffusion, from the fluid within the joint. And so all of these things in combination make it difficult for the articular cartilage to heal on its own in adults, which is why this has been such a problem in the past for orthopedists, when we were dealing with the injuries previously, there wasn't a lot of great solutions other than to maybe clean up the debris or the flap or the floating piece in the knee. And hopefully the knee wouldn't continue to deteriorate into more of a global arthritic picture. We would merely try and hold off that diffuse injury and thinning until the patient was old enough for a joint replacement.

So, now the good thing with newer treatments, specifically the ones that I'm interested in for focal cartilage defect, being able to treat these injuries, surgically, hopefully we can not only fix the injury, but we can prevent any further wear and tear that might propagate and then lead to a more global picture.

Host: Well Dr. Redshaw, and we're going to get into treatments in just a minute, but briefly, can you tell us any symptoms that a patient would have since it doesn't really have pain fibers? Correct? So the pain symptoms may not be equally proportional to the amount of injury in some cases. How do we know, how do you diagnose it? Is an MRI? Is that not really great for this? How do we know this is the situation?

Dr. Redshaw: Yeah, that's a good point because articular cartilage does not have pain fibers itself. Most of the time, the early symptoms of focal cartilage injuries include mechanical symptoms, such as a strange clicking in the knee. The knee could catch and not glide as smoothly as it does. You might have limits in range of motion. Your knee could become locked from the loose body of that articular cartilage floating around freely in the knee. That's also doesn't mean though, that these injuries are not painful because when you do have cartilage injury, it places a substantial amount of stress on the surrounding cartilage and thus the supporting bone and the bone is extremely sensitive to pain.

And a lot of the times, when these patients do experience pain, it is from subsequent bone marrow edema and increased stress on the bone, in that area of the cartilage lesion. And you were right on about needing an MRI. A lot of the times the MRI, can help see mostly the soft tissue structures in the knee, but can also help with the articular cartilage on certain sequences. It can eliminate not only the location of the injury, the size of the injury, any possible loose bodies floating in the knee, any subsequent bone marrow edema or swelling as a result of this injury. And also times a lot of these injuries happen, in combination with other soft tissue injuries, including ACL tears, meniscal tears, or even patellar dislocations and things like that.

Host: So, then tell us about some of the treatment options available and your interests in this particular type of injury. If you could briefly go over some of those treatment options for us.

Dr. Redshaw: Right. When we speak about articular cartilage injuries and the treatment options available now, obviously you can always start with conservative care, which would include non-surgical treatment options. Usually this involves just treating symptoms and pain, however. If you really want to get at the issue of the focal cartilage defect, a lot of the times this will require surgery, usually arthroscopic procedures, first off to not only evaluate the knee and the integrity of the cartilage, but also to size the defects, clean away any capsular debris, as well as any loose bodies that might be resulting from the cartilage injury. There are three main treatment options when it comes to restoring the cartilage defect. The first one would be an autograph technique where you take a cartilage plug from the same knee in an area that's less demanding on the cartilage and you place that healthy cartilage plug into the area of injury or defect.

It's usually more necessary for weightbearing and function of the knee. This treatment option is usually younger patients and provides a good option for small defects. The second option would be an allograph technique where you are able to take a corresponding cadaverknee with a appropriately sized cartilage plug five match for the patient's defect, and you're able to replace the injured cartilage with a fresh frozen cadaver plug which can be used for adults of any age. It can fill essentially any size defect and it's a one-time surgery that usually permits for earlier return of function. The last option is the newest technique and it involves taking a cartilage sample from the patient of healthy cartilage cells, sending that to a lab, where in the lab, the cartilage cells are propagated to upwards of 5 million cells. These are placed on a membrane and then the membrane is shipped back sterilely, and then the patient would undergo a second procedure where the cartilage implanted membrane would be placed in the defect and allowed to subsequently grow and proliferate over the next several weeks and months. And thus the patient has their own cartilage cells filling the defect, which could be used for again, larger areas.

Host: That is so exciting and absolutely fascinating. What an exciting time to be in your field. As we wrap up Dr. Redshaw, tell us a little bit about cartilage restoration rehab, and since patients or an athlete have to be able to accept the load of the sport or whatever it is that they're doing. Tell us how this necessitates a multidisciplinary approach to rehabilitation and transformation from that transition from therapy to performance care. Wrap it up with your best advice about this type of rehab and what you'd like listeners to know.

Dr. Redshaw: The main thing with any cartilage procedure, is that the rehab is fairly intensive. I like to say that it is not for the faint of heart because the recovery process from these surgeries is usually the hardest part compared to what we actually do. There's going to be a time of protected weightbearing because we need this cartilage to heal.

We already talked about how difficult it was for cartilage to heal itself. We still need the surgical procedures to heal in place if we really want long-term results. And so rehab generally involves not only a time of limiting the weight bearing on that limb, but also intensive physical therapy afterwards with a dedicated physical therapist that work on anything from range of motion to strength. And then focusing on getting back to your dynamic exercises or whatever activity or sport that we're trying to get back to. The main thing, like I said, this cartilage is very precious. And so the rehab is a significant part of the process and having that time to allow it to heal and really take hold is what allows for not only success in the short term with pain relief and return of function, but long-term health of the joint, avoiding osteoarthritis and getting everyone back to their preferred activities and sports.

Host: Thank you so much, Dr. Redshaw for joining us and sharing your incredible expertise with us today. You can call 765-962-4444 to schedule your appointment today or for more information, you can always visit Reidhealth.org to get connected with one of our providers like Dr. Redshaw. That concludes this episode of Right Beside You, a Reid Health podcast. Please remember to rate and review and subscribe to this podcast and all the other Reid Health podcasts. I'm Melanie Cole. Thanks so much for listening.