Hi, my name is Norman Waldrop, foot and ankle surgeon at Andrews Sports Medicine in Birmingham, Alabama. Today we're going to talk about osteochondral lesions of the talus, not just athletes, but all others. Kind of look at the various modes of treatment and where we stand in today's world. Have no disclosures related to this talk. I am a paid consultant for Arthrex and Crossroads. These are my disclosures. Certainly looking at the history of the OCD, it goes back a long way, right? Sure, as long as time, but they were first described in 1856. The term OCD was coined by Koenig in 1888 when describing lesions of the knees seen on an x-ray. If you look at the various classifications, there are multiple out there. The Burton-Hardy classification is one of the most common that's out there. On page 1-4, there's the ICRS and various other imaging-based classifications out there. Originally, this was a historical diagnosis made based off the history of physical patients that complained of mechanical symptoms and swelling with clicking, popping, catching in the ankle itself, radiographs, certainly. As they improved over time, it became a better way to diagnose them, though those of us who treat this tend to understand that they underestimate the size and the extent of the lesion. More advanced imaging techniques have become the primary way of evaluating these lesions, both CT scans to evaluate the bony component of the lesions, as well as MRI to look at the cystic aspect of it, fluid, the soft tissues around it, and even some of the cartilage mapping involved with these. Treating these can be very difficult, and you'll see we'll go through all the different techniques that are out there. Certainly, non-operative treatment was the mainstay of treatment until many of the arthroscopic techniques evolved. Oftentimes, that meant a cast, a period of time of non-weight-bearing, often 6-8 weeks. Even as recent as an FAI back in 2000 showed that this was only about a 45% success rate, so flip the coin. Outcomes weren't great, so we began to look at other avenues. Operative treatment became often the mainstay in patients that were symptomatic. Arthroscopic debridement and bone marrow stimulation was certainly the first line of defense for these. The results showed an 80-85% success rate. Champ Baker, out of the Houston Clinic in Columbus, Georgia, published his first results and was one of the pioneers of this early technique back in the late 70s and 1980s. There have been, obviously, multiple, many, many studies that have looked at this. Certainly, probably the most common or the most important parts of this are outcomes that are based primarily on the size of the lesion and the age of the patient. How do we fix these? We talked about bone marrow stimulation, which is probably still worldwide the most common, but there are other techniques out there. Osteochondral autograft transplants, an OATS procedure using either a contralateral or ipsilateral knee, can be seen as a primary procedure or a revision for failed microfracture where a plug is taken out of the knee, size-matched and placed through an open technique into the talus. It's typically used for lesions greater than 1.5 to 2 centimeters. Certainly, some of the newer scanning techniques that we have can provide a better road map and improved outcomes. Hangedy was one of the first to publish on this back in JBGS in 2023 and, probably, most importantly, he showed a small morbidity rate of only 3%, but the success rate that he showed was greater than 94%, so it certainly got people excited about that technique. Many people, however, don't like going to the knee and creating another site, including donor site morbidity. Osteochondral autograft transplants became more common. There was no donor site morbidity, however, there was a significantly increased cost and multiple studies showed that there was no difference between the autograft and the allograft other than higher cost. But, certainly, there's some concern for a higher non-union rate given the fact that this is a cadaveric specimen and could potentially risk for non-union of the bone to heal. ACI, which is autologous chondrocyte implantation, was first described in 2005. This is, unfortunately, a two-stage technique. It requires harvest and culture in a lab, growing the chondrocytes, and then re-implantation back into the talus. It requires well-contained lesions, so lesions that get into the shoulder of the talus don't do as well. Meta-analysis questions the use of this technique published back in 2012 in KSSTA because of the significantly increased cost and morbidity of two-stage procedures didn't tend to jive well with outcomes that weren't significantly improved. MACI, which is a matrix, utilizing a matrix, was improved by the FDA back in 2017. It obviates the need for the periosteal patch, which was described with ACI and doesn't require quite the extensive joint exposure of the osteotomy and oftentimes has been proven to be efficacious. However, this technique's not near as common. Juvenile particulated cartilage did significantly increase in usage from essentially 2010 on. This was a Zimmer product. It was a particulated juvenile cartilage that was a single-stage procedure. The high cost, though, did limit its usage. Oftentimes it was difficult to get it approved. It is becoming more commonly used now. Several studies have demonstrated good outcomes well over a year. Most importantly, though, they did seem to be size-dependent. Micronized cartilage matrix, which is one of even the more newer techniques, is essentially a scaffold to allow the proliferation of the chondrocytes to grow within the lesion. No significant long-term results available. It's one of the newer techniques over the last five or six years, but it has been shown by Shi and his partners in Cartilagin 2020 to be an excellent proof of concept with good outcomes in the first 24 patients that he treated. Mark Dracos compared the micronized cartilage matrix to microfracture alone, which showed that they had improved MoCART scores relative to microfracture. He published his results in 120 head-to-head patients back in FAI in 2021. PACE-E, Particulated Autologous Chondrocyte Implantation, is also one of the newer techniques that uses a trap that you can see here to catch the cartilage lesion and to mince it. It allows us to harvest it, prep it in a single procedure, mix it with BMAC or PRP, and re-implant it. This has also been shown to have good outcomes. It's in a two-year outcomes by Lopez published in Cartilage. They had excellent AOFS scores of 90 and MoCART score of 73 in his first 24 patients. There are some other techniques out there that are a little more of the fringe. I won't get into those quite as much. This kind of sums up my thoughts on those. Biologics though are an important part of this process. PRP has become much more mainstream in the last decade. Research is trying to catch up to that. It has the potential to enhance the healing environment. One of the issues, however, is that there's very little consistency across the board. It makes research a little bit difficult. There is some promise in conjunction with bone marrow stimulation, but where that actually goes and will we see better outcomes with the particulated juvenile cartilage or the micronized cartilage matrix remains to be seen a little bit. BMAC, it's also become more common over the past decade. It isolates the pluripotent cells of the mesenchymal cells of the iliac crust. It has potential for improved graft engrowth, which I think is important to allow for that chondrocyte proliferation. Kennedy and his partners out of New York were the first to show improved outcomes with graft in BMAC. I think many people do use it as an adjunct with some of the techniques that I already described. There are some other techniques out there, embryonic-derived mesenchymal stem cells that are still in the early investigational stage. There's no real in vivo data in the ankle. It's controversial. There's still a lot of questions that need to be answered before we dive deeper into this. What are we really using? What about in the acute setting? It's a little different. What are we doing for athletes? I'm going to show one case real quick. This is an NFL running back who had a mesenov fracture dislocation. He'd had a previous injury on the contralateral side. You can see here the proximal mesenov injury and the deltoid avulsion on the medial side. Here's his stress injury. It's clearly unstable. He was treated with a four-hole plate, one flexible end-to-button construct with a screw, which I do in the mesenov setting, remove that screw down the road and replace it with a second flexible end-to-button. Unfortunately, he did have a fairly large osteochondral lesion of his talus that was acute. How do we treat these? If you think about it, one of our worries is using microfracture bone marrow stimulation techniques. Can that cause edema and cysts that can be persistent? Can this lead to further issues down the road? Two to four years later, you don't get the appropriate healing environment, it leads to cysts and further troubles for that patient. Because of this, I have gotten away from microfracturing in the acute setting, oftentimes just using a burr to score the subchondral bone and letting the traumatic environment heal the lesion. What do we do post-operatively? Some believe that weight-bearing and motion are contradictory for OCD healing. Weight-bearing creates a shearing force, whereas the motion creates a smoothing or conforming force for it. Systematic reviews show no difference with delayed weight-bearings and the recommended early weight-bearings. It can be difficult to decide. Personally, I do four weeks of non-weight-bearing, but I believe that motion is essential for swelling control as well as for shaping the lesion, so oftentimes I will take them out of their either boot or cast a little early and start motion. I'll have them full weight-bearing by six weeks and in regular shoes by eight weeks. How do you treat? In today's world, there are all different kinds of techniques, from micronized cartilage matrix to the plugs of the OATS procedures and microfracture. I've gotten away from some of the larger procedures and certainly use those for more tertiary failures and rely more heavily on the micronized cartilage matrix type procedures, the arthroscopic techniques first. There are many options available. The meta-analysis didn't show a difference in bone marrow stimulation in some of the osteochondral grafting techniques looking at 317 different talus. Our outcomes are still in that 80-85% success rate, so how are we going to get them better and can biologics get us over that hump? The size of the lesion and the age of the patient tends to be the most critical and I have that discussion with the patients when I'm counseling them on what their expected outcomes can be. Can we speed up? Ultimately, you have to let the body heal it. Still 3-4 months is returned to play as a reasonable goal, but unfortunately it's difficult to push this any harder because it certainly will push back. Ultimately, techniques continue to evolve. Biologics are decreasing in cost and have promising early research to support their use oftentimes in conjunction with other techniques. It's likely a combination of many of the above techniques will provide the success we're looking for. However, we're still searching for that holy grail. Thank you.

foot and ankle surgeon

osteochondral lesions

diagnostics

treatment options

advanced imaging techniques