Knee Case Review: Adult Female Chronic Meniscus Tear
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Okay, this is an older woman,
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not going to say what's older
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to be politically correct in the current environment,
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but she has a meniscus tear that is
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not unique to anybody over the age of 50.
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In fact,
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the overwhelming majority of people over 50,
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you're going to have something like this
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that's maybe a little less severe.
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And what does she have?
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She has the typical chronic body cleavage tear
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in a pseudo extruded lax meniscus
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whose attachments have grown progressively
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more lax over time due to the altered
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hoop stresses and tension from the femur,
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pressing down on the tibia.
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Part of this exacerbation of hoop stresses
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comes in the form of bony remodeling.
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The femoral condyle is not a
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nice half circle anymore.
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Kind of has a little bit of a dippity-do right here.
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It's also shifted.
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You can see the femur is shifted
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relative to the tibia,
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and that doesn't do the lateral meniscus any good.
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In fact,
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it's a very unfriendly phenomenon
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to either meniscus.
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It's also a very unfriendly phenomenon to the knee notch.
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Because now, you've got these spines
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that are pressing against,
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or in some cases,
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tugging on the cruciates aberrantly or abnormally
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because you're no longer aligned straight up and down,
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so you end up with some notch synovitis.
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So notch synovitis,
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remodeling shift and meniscal pseudo extrusion,
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or meniscus displacement from meniscal capsular laxity,
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they all go hand in hand.
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These are not surgical menisci.
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You can't fix this.
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Person's lying on their back,
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the meniscus is not even sitting
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between the femur and the tibia.
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It's doing the patient no good supine.
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So imagine how little good it does
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than when they are standing up.
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Never should you see signal in the
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inner third of the meniscus,
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at least not in a normal person.
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You're going to see it in just about everybody.
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As we said, over the age of 50,
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certainly over the age of 60,
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these are a source of pain.
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They are not resected.
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They are usually either injected
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or they're treated with lubricant
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injected into the joint,
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steroid injected into the joint,
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or some unloader brace
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until finally the patient requires a total knee replacement.
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Now, one of the reasons why these tears
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are so often underdiagnosed,
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and maybe it's a good thing
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that you're under diagnosing them
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because then they won't have an unnecessary resection.
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But if you're going to diagnose them,
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call them incidental,
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trizonal, horizontal, cleavage tears
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in a degenerated knee.
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If you really want to slam the door shut
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on a surgery,
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call the tear degenerative,
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although some surgeons may object
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to that descriptor.
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Now, again,
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one of the reasons why this tear is so often undercalled
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is because it's hard to see in the sagittal projection.
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It's coming straight at you,
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right?
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It's kind of like a line.
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Here it is.
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There is the tear.
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It doesn't often articulate with an articular surface
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because it's coming into the screen.
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It's going from medial to lateral.
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So, you're cutting it like you're cutting through
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a turkey sandwich.
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So, here's the turkey.
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The dark is a piece of bread,
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and the other dark is the other piece of bread.
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So, that is the same tear as this,
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just coming straight at you into the sagittal projection.
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So just for emphasis,
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tears that are shaped like this in degenerated knees
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that begin in the inner third
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and kind of go straight out
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and get a little irregular
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and somewhat mushy looking,
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they're non-surgical tears.
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They're common,
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they're chronic,
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they're often degenerative.
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They're even more common in women,
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and they're especially common in people
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who are overweight.
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Let's do another one, shall.
Stephen J Pomeranz, MD
Chief Medical Officer, ProScan Imaging. Founder, MRI Online
ProScan Imaging
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