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<v ->Let's move on next to the superior plica.

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And the superior plica is located just

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above the patella one or three centimeters.

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And if you look at its course,

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it extends from a most posterosuperior portion

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to a more anteroinferior portion,

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so it extends obliquely downward.

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It may have an opening,

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that opening is called a porta, P-O-R-T-A,

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or it may be complete without a porta.

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Most of the plica will have

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at least a small opening associated with them.

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Now, I wanna tell you why these become symptomatic.

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As you look at this normal superior plica,

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you can imagine that what happens in a normal joint

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such as the knee joint, is as you move the joint,

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the fluid, the physiologic fluid moves

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around the joint from one portion to the other.

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But if you have a plica,

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particularly if it's thickened, that normal distribution

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and movement of fluid is interrupted.

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And so what you're gonna see is the effects

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of abnormal movement of fluid and stasis of synovial fluid

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that will lead to the symptoms of superior plica syndrome.

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It's probably uncommon to see this.

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It's associated with a thick superior plica,

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and it leads to abnormal compartmentalization of the joint.

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So here in one of our cadavers,

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you're seeing a thickened superior plica

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that at least on this image is complete.

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It probably was slightly incomplete

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on other sagittal sections,

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but you can see how it kind of isolates this part

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of the suprapatellar recess

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from the remaining portions of the joint.

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It creates stasis.

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So what you end to up with in many of these cases

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is a focal synovitis located either slightly above the plica

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or slightly below the plica, or in both locations.

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Okay, that's what you're kind of looking for in this.

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And you can see here by the way

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maybe a slightly thickened medial plica as well.

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Here's another example.

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And on this one, we could see with conventional radiography

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on your right kind of some fibrofatty areas

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of synovial proliferation producing some radiolucency

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in an area that has also some increase radiodensity.

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And this is what it looked like.

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It's an old case, but again, you can see the superior plica.

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And look at all of this synovial proliferation mainly below

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but a little bit above that area of that plica.

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Now, once again, there's a classification system,

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A, B and C.

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A representing a complete septum without a porta,

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B by showing you a porta, and C said to be more

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of a crescent-shaped appearance to the plica.

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Let me show you a few examples.

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Here is a slightly thickened superior plica

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with synovitis and synovial proliferation located

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above the level of the plica,

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again due to abnormal movement of the synovial fluid.

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Because of that abnormal compartmentalization,

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disease processes can localize above the plica.

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Here's an example where most

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of the intraarticular bodies associated

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with osteophytosis in this case are located superiorly

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within the suprapatellar recess.

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So this is kind of a funny looking appearance.

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There were some osteophytes,

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and I think there were some bodies elsewhere,

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but almost all of them had eventually become located

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above the thickened plica.

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And the same for pigmented villonodular synovitis,

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that I have seen a number of cases

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because of abnormal compartmentalization,

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that the disease process here PVNS was located only

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in that segment of the joint above the abnormal plica.