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<v ->Now, there are a lot of patterns of cartilage failure,

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but generally they relate to compression or sheer forces,

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or both types apply to the surface of articular cartilage.

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And the names you use,

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I don't know exactly what they are in your language,

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but in our language, we're very specific

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about the terms that we use.

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Fibrillation comes from the English word, fibrillation;

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process of forming fine fibers or fibrils.

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So when we talk about chondral or cartilage fibrillation,

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we're talking about a surface phenomenon

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with slight irregularity of the surface

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of the articular cartilage.

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It's in the layer of lamina splendens.

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Fissuring in the English language means a split or crack

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that is long and narrow.

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So when we talk about chondral fissuring,

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we're talking about these vertical clefts.

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Here, the arrow pointing to one of them.

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Chondromalacia, well in the English language,

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malacia means abnormal softening of tissue.

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Chondromalacia, osteomalacia, laryngomalacia.

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For chondromalacia, the main abnormality we see

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is an alteration and signal intensity

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typically within the midzone of the patella.

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All right, now I know orthopedic surgeons

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talk about grade two, grade three, grade four chondromalacia

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for virtually every single cartilage abnormality,

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but that's not the derivation of the term.

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It refers to a specific pattern of softening

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of articular cartilage

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that leads to signal intensity changes.

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And then we come to the word delamination.

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So once again, let's go to the English dictionary.

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If you look up the word delamination

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in the English dictionary,

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it's a mode of failure

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in which a material fractures or separates into layers.

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So if you're talking about,

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and using the term chondrodelamination,

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keep that English definition in mind.

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Yes, we see chondrodelamination,

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I'm gonna show you exactly what it is in a few minutes.

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But you see, delamination is not a new phenomenon.

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It occurs in a lot of structures.

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Here are pictures of delamination of cement,

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delamination of ceramic,

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delamination of wood.

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Layers, separation of one layer from another.

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When we talk about delamination of a tendon,

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or of a ligament,

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we talk about a specific pattern of failure

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between collagen bundles.

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That is what a delaminated tear is.

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So, if you have a purely delaminated tear of a tendon

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or of a ligament,

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it's a collagen's sparing tear.

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And if you test the muscle that owns that tendon,

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that muscle strength would appear to be normal.

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So tendon and ligament delamination

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specifically one direction parallel to the long axis

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of the collagen bundles.

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Now you see the problem.

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When we deal with articular cartilage,

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we have columns of collagen and we have rows of cells.

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And so we have two patterns of delamination,

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depending upon what you are using

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as your point of reference.

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If you're using collagen columns,

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you're talking about vertical delamination,

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and one pattern of transverse delamination

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that I'll show you.

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If you're talking about delamination using cellular rows,

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you're talking about horizontal delamination.

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Two patterns can be seen.

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So you will see in fact,

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drawings like the one I have created here

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of what may represent delamination of articular cartilage.

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Number one is a horizontal vector of failure

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in, not the middle zone,

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but a lower zone of articular cartilage.

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You are separating rows or layers of articular cartilage.

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Number two is different.

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It's occurring at the base of a cartilage

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in the area of the tidemark

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separating most of the cartilage

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from the calcified layer and subchondral bone plate.

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That is delamination using collagen columns

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as your point of reference.

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So, let's look at an example

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of delamination of cellular rows.

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This one is obliquely oriented, a nice specimen.

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It's not from the patient images you see below,

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but it looks very, very similar.

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So this is an obliquely oriented pattern

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of chondral delamination with a horizontal oblique direction

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disrupting the surface,

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so it would be visible to the arthroscopist extending down.

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Here, we look at these images to the midzone

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separating rows, cellular rows.

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Let's look delamination using collagen

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as our point of reference.

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One pattern would be vertical in nature,

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parallel to those columns

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are arcades of collagen of Beninghoff.

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And so this pattern we would call chondral fissuring.

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Chondral fissuring is cartilage delamination

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parallel to the arcades of Beninghoff.

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A second pattern of chondral delamination

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related to collagen occurs at the tidemark.

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That is an area in which sheer will lead to failure.

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So this is horizontal delamination.

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Look at the case below.

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We see an example of delamination of cartilage

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mainly related to collagen orientation.

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This particular pattern is producing surface disruption

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with deep chondral fissuring,

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and then separation of a long segment

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of articular cartilage at the tidemark

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in the lower area of the articular cartilage.

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Surface disruption.

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During arthroscopy, this would be clearly visible.

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But how about this one?

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Here, we see chondral delamination at the tidemark.

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But the surface of articular cartilage,

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although bumpy and irregular, is not disrupted.

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A good arthroscopist would be palpating that cartilage

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and realize it's too movable

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and be able to predict that there's deep delamination,

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but it's hidden to some extent

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as the surface is not disrupted.