 History. Nineteen-year-old female, hyperextension, while dancing. Nine days ago, prior to this study, pain in the popliteal area, severe pain with straightening. I'm going to drop down all the water-weighted sequences first, and you can see that as typically a habit of mine for efficiency and speed. I've already established in my mind that something's wrong with the ACL, right off the axial. Where is my straight, linear, hypo intense ACL that should be hugging the inner border of the lateral femoral condyle? It's not there. It's torn right there. We already know there's an ACL tear before we've even looked at anything else. Just on our so-called axial scout, we know that the intromedial tibial collateral ligament and the superficial layers that include the retinaculum and the MPFL and the patello tibial ligament and the patello meniscal ligament, they're a little bit abnormal. They're puffy-looking. We go to the coronal. Once again, we've got micro-tribecular impaction injury, subcortical micro-tribecular fracture. This one, I don't think was depressed. Actually, slightly depressed. Very slightly depressed. On the T1 on the lateral side. So we know there's been a pivot shift. Let's keep looking, shall we? Our theory that the MCL was injured anteriorly was correct. There's blood. The superficial fibers of the intromedial MCL, irregular, ill-defined, not contiguous. The meniscofemoral anterior ligament, ill-defined and swollen. But to your question earlier, look at those condyles. I like to see a ratio of about 0.8 medial to lateral femoral condyle. So the lateral condyle is always a little wider. The lateral meniscus is C-shaped. So this one is not a ratio of 0.8. In fact, it's another example of a condyle that's hanging too low and it's too narrow. It's displastic. Let's keep looking, shall we? I've now got up a T1 on the far right. I'm going to bring down my water-weighted T2 and blow it up in place of my axial just to show you that there is no ACL anymore. It's gone. Filled with shredded fibers of the ACL, blood and gore. All right, let's pull down our water-weighted sagittal. In a long-standing ACL, usually what you get is scar tissue that forms a pseudo-ligament that can simulate an intact ligament and sometimes actually behaves as a structural functional ligament. This has happened in my own family. One of my first-degree relatives had an ACL tear, non-operated. It scarred to the PCL. She has done fine. Knee is completely stable. All right, let's keep looking, shall we? Some of you have noticed that the meniscus on the medial side where the displage is too long, too deep. The meniscus in the midbody should always be a triangle. It should end or truncate right about here. That's what the meniscus should look like in the body. Got all this extra tissue, a tongue. The patient has a Discoid Medial Meniscus. One out of 100 to one out of 500 Discoid Menisci are medial. So I'm not common. So we have dysplasia, Discoid Medial Meniscus. There is intraminiscule signal. Now, typically I don't mind intraminiscule signal in a 19-year-old. I don't mind it at all. But in a Discoid Meniscus I mind it a lot, especially if it's not centric. What do I mean by centric? In the middle with two little bunny ears. This one is not centric. It's eccentric right there. It's not symmetric. That fascicle is a little brighter than that fascicle. So there is an intraminiscule injury which you're not going to touch because you can't. You're going to call it an injury because you don't want them to touch it. That's what the word injury is for. Don't touch it. Tear. Unstable tear. Complex tear. Those are acute, aggressive words. That means you want them to touch it. You are in a position of enormous power. You just don't realize it. What you say is on paper forever. It's electronically there forever. You are speaking code. You are speaking in tongues. In this case, your tongue says meniscus dysplasia, intraminiscule abnormality in your mind. Probably intraminiscule tear in a Discoid Meniscus because they always are. And you know this from experience over time. You might call it a contusion because there's a contusion underneath. You might look for a ramp lesion because you know the ACL is torn. There's a lot here. There's a micro-tribecular fracture there and there. Let's check out the posterior menisco capsular reflection. Swollen, ramp one. Plus there is a posterior menisco tibial ligament that goes something like this. So it's this thing right here. And then it goes down around the back. Look at what's happening down around the back. Swelling, no ligament, a fracture. So the infro posterior menisco tibial ligament is torn. There is a ramp lesion at the capsular interface. There is an intraminiscule injury in a Discoid Meniscus. There's an ACL transsection. I don't think we're done. We've got a lot more. We do have contular dysplasia, yes, which we mentioned. And we also mentioned that the patient had a valgus moment with a low-grade MCL. Superficial cruces swollen, tibial collateral intact, menisco femoral ligament intact. Let's blow it up. See it a little better. There it is. Menisco tibial ligament or coronary ligament intact. We're good. So conclusion. Meniscal dysplasia, contular dysplasia, Discoid Meniscus, intraminiscule injury, Discoid Medial Meniscus, ramp lesion, Discoid Medial Meniscus, ACL transsection with low-grade valgus moment and low-grade MCL. You can put the micro-tribecular fractures in the body. Could I point out the ramp lesion? When you see this exaggerated appearance of the capsular reflection, it's too clear. And this swollen tissue, especially right here. Now, granted, you might say, well, that's right over a fracture. It's true, fracture, bleeding. You say to yourself, OK, is that just bleeding from the fracture? So you have to follow this thing. You have to follow that ligament. So that ligament is not, it should plunge down behind the tibia. It is not. So it's this, it's this, and it's all this tissue. Too much gray, thick tissue. And by the way, look at the capsule. Little wavy, isn't it? The wavy line sign. That capsule got dinged a little bit, too. What grade? As you know, just with pirads and pirads, you know, grades don't always work. So you would call this a grade one. However, most advocates of ramp lesions feel that when you lose the inferior menisco tibia ligament, that it's a more serious type of ramp injury. So classically, this would be a ramp one involving the capsule. But as I said earlier, it's a ramp one plus. Because you've got the capsule and you've got this menisco tibia ligament that's affected, which is usually affected with higher grades of ramp lesion. So it doesn't perfectly fit in to any one of the ramp lesion categories one through five. What do I think about the anterior horn of the lateral meniscus? I didn't think much about it, but let's have another look at it. Here it is. Now, the anterior horn of the lateral meniscus is really a problematic area. And here's why. So nice C-shaped lateral meniscus, a little thinner up front, so not as wide here as it is back here. It's pretty long. It's got a long tongue in the front. The medial meniscus is usually more C-shaped. And when you get to the front of the lateral meniscus, remember that the ACL is coming right to it. And the root ligaments are going to blend with the ACL. But another thing happens. The root attachments and the capsular reflection interdigitates with the anterior lateral horn and gives you plenty of horizontal signal. So if you look at the meniscus laterally, sometimes it'll look like this. You'll see a little wisp in it. This is at the root, the anterior horn root area. So all the way around this locus. So it might even look like this. It might even be a little bit oblique. It can come in obliquely. It can come in horizontally. So your question is a commonly asked one. You might say, okay, well, when do I diagnose a tear? When you have swelling around it. When you have a conral lesion around it. And when it goes to here. When you do your sagittals and you start to get into the body horn junction and it persists, it's a tear. If you have a cyst, it's a tear. If you have a large area of blood next to it, it's a tear. So you're going to use a combination of morphology and the indirect signs of swelling to decide. This one is not a tear. Let's look at it again. Just to be sure. You know, we miss stuff too. That's the medial side. Here's the lateral side. And that is that interdigitation that I showed you. Now, you might say, well, that's right over a fracture. You're right. It is right over a fracture. And there is a conral injury there. That's the interdigitation I told you about. But it doesn't go into the body. So why is that look a little more conspicuous? Because it's capsular tissue that's been compressed. So it isn't normal tissue. It's swollen tissue. But you're going to see that in virtually every terminal sulcus injury. We would call this a subcortical, subconral, pivot shift-related microchrobacular fracture. And if you want, you could call this a meniscus contusion, because it is. And if you were wading through the body of the report, you would probably call that an osteocondral microchrobacular fracture. Because the conral tissue, not normal. Blow it up. Gray, normal. White, abnormal. So there is an osteocondral injury there. There is an impact injury there. But I would not use the T word in this case. You're going to see something very similar to this in almost every meniscus, not quite as bright. Thank you.