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There are three classic patterns

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of displaced meniscal tear.

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A bucket handle tear, which is a uh, a displacement

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of a longitudinal vertical tear.

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A flap tear, which is a displaced horizontal tear

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and a radio tear displaced.

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We call that a parrot be tear.

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I show you here some examples of them.

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This is the bucket handle tear with a flap

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of tissue present within the central aspect of the knee.

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Here is a horizontal tear with a flap extending down,

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eroding the peripheral margin of the tibia.

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And here is a bar the tear, we've already discussed that.

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So let's talk about bucket handle tears.

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Now in general, what we're dealing

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with are longitudinal vertical tears occurring in the

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peripheral portion of the meniscus.

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We call these bucket handle tears,

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although I'm not sure exactly why

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because typically the peripheral aspect is thinner than

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the central aspect.

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Yet the peripheral aspect is the bucket

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and this is the central portion of the bucket handle.

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Tear the handle of the bucket, handle tear.

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There are three diagnostic criteria that we have

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for a classic bucket handle tear

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numbering them here for you.

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Number one, peripheral rim of meniscal tissue.

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Number two, centrally displaced meniscal tissue.

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And number three, a connection between the peripheral

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and central portions, both anteriorly and posteriorly.

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So here I show you with coronal images, the take off

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of the bucket handle tear.

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Here we follow it continuously, centrally

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and we can see in fact now it connects

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to the posterior horn.

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All three criteria have been met.

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This is a bucket handle tear.

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We all also recognize these hairs

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because we end up with tissue flaps

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of the meniscus located centrally for a bucket handle pair

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of the medial meniscus, the so-called double PCL sign

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and what I call the pseudo torn ACL sign

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for a bucking handle pair of the lateral meniscus.

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This looks like a torn ACL,

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although the ACL is located behind it and is intact.

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Now there is a pattern that I don't think is well recognized

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in the radiology literature

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that is called the consular entrapment pattern.

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So I'm gonna show you what this relates to.

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This relates to a bucket handle tear

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with progressive inversion of the central meniscal tissue.

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So it ends up upside down. Okay, located centrally.

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And if this occurs, there is kinking

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between the peripheral aspect

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and the central portion of the meniscus.

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And further that inner margin of the bucket handle tear may

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Work its way up along the inner aspect

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of the ipsilateral femoral condyle ENT trapping

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that femoral condyle.

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Now this is an interesting type

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and it is probably fairly common.

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And when you have that, particularly when you have kinking

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owing to the inversion of the central part, you will see

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what has been called AV sign like this, okay?

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Right at those areas of distortion connecting the peripheral

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and central portion, I've seen this most commonly involving

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bucket handle pairs of the medial mucus

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and located anteriorly as shown here.

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So I'm showing you two cases here of the V sign.

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A very important sign.

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Both of these involving the anterior aspect

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of a bucket handle, tear of the medial meniscus.

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Now in addition,

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if the bucket handle tear is not treated immediately,

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you can end up with brakes in the handles

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or buckets that are leaking.

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So here would be a broken handle

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and this would be a peripheral rim failure,

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A leaking bucket, just to show you an example of

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that here in fact is a bucket handle pair

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with further tearing of the peripheral portion.

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We're dealing with a leaking bucket handle tear

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with regard to the repair.

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Uh, repairing these, there are certain criteria

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that generally indicate these

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pairs can be repaired rather than resected.

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A peripheral segment that is less than four millimeters

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tear length equal two or greater than 10 millimeters,

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and minimal damage to the central or peripheral segment.

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And here's a case where in fact this is a nice, uh, tear.

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It's occurring actually at the meniscal capsular junction

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and, uh, taken from the literature, this is one

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that could be repaired.

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Finally, to complete our story, be aware

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of the Hemi bucket handle tear typically associated

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with longitudinal horizontal tears involving the meniscus.

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Generally of the inner margin, you may end up with a flap

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of meniscal tissue essentially,

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and the peripheral part doesn't look too bad there.

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These are two cases showing you minor irregularity.

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So some of the meniscus has displaced essentially

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and some remains intact, known as a hemi bucket there.

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And then also the flip meniscus where the point

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of failure is not within the meniscus

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but is at the meniscal capsular junction.

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You see this most commonly on the lateral side in the region

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of the posterior horn of the lateral meniscus.

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And indeed this is an example,

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beautiful picture from Mike Sta.

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And this is what it might look like on the MR images.

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Meniscal capsular

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Injuries are uncommon, all right?

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They are hard to diagnose, typically they don't occur alone.

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They're associated with other abnormalities

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including ligament failure and discoid meniscus.

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More common on the medial side.

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Okay, difficult MR diagnosis.

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And if they are long, they may require a repair

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with multiple sutures.

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I show you a discoid meniscus with separation here.

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Meniscal capsular separation.

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This is an ACL tear, a ramp like lesion, a failure adjacent

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to the posterior horn,

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and a similar one here with a partial separation.

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Note that very important clue, the edema posterior aspect

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of the medial tibial plateau.