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Okay, we're in our office together, and, uh, we've

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got a 63-year-old male with medial ankle pain.

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I've got up my T1 on the left, my proton

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density fat suppression in the middle,

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and on the right, I've got a gradient echo,

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which is more of an articular sequence,

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with very thin sections called adage.

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But if I'm in the reading room with you,

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or we're in my office together, because

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it's medial, eccentric to the inside,

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eccentric to the outside, I'm going axial

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first because I want to be efficient.

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If you're not efficient, you're not valuable,

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and if you're not valuable, you're out of a job.

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So, now I've put up my axials,

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and I've got three sequences.

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My proton density fat suppression, which

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is my user-friendly, sensitive sequence.

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In the middle, I've got my T1, my

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all-purpose anatomy sequence, and

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sometimes a modifier for fat and blood.

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And my T2 on the far right, which

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I'm going to use for dating.

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Not for online dating, but for actually

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dating the age of an abnormality,

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and what's inside the abnormality.

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You know, do I have fibrous tissue

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inside, cystic tissue, and blood?

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And I'm going to go back and forth between

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these sequences to make those decisions.

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So, I've been told that I've got medial

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pain, rule out posterior tibial tendon

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tear, and so naturally, I'm going to

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scroll my images and follow my posterior

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tibial tendon, all the while keeping an

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eye on the other flexors, which I've done.

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And you're all aware, if you're

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not, you will be, that the posterior

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tibial tendon is a very skittish tendon.

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It can do anything, go anywhere, be

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anyone because when it gets to the

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bottom, it sends branches and insertions

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to virtually every single bone in the foot.

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You can see a lot of these little

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spots going off to the side.

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Then it comes back together as an arc,

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and it normally inserts on either an

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accessory navicular or contains an

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accessory bone or inserts on the navicular.

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And so far, unimpressive.

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I will allow about a millimeter of fluid

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around my posterior tibial tendon, but that's a

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little more than a millimeter, so my posterior

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tibial tendon intrinsically is okay. There's a

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little bit of swelling around it, and there's

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a scant amount of fluid around the FHL.

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So why? Why do I have medial pain?

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Thank you.

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Well, there's some medial soft tissue swelling.

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Could it be just swelling?

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Maybe the patient had a contusion.

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There's no history thereof.

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I'm thinking about the case the way I'd think

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about it if we were together by ourselves.

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So now I'm going to wrap my way around

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and still stay medial and go over to the

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EHL. Because the extensor hallucis longus

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is going to go to the great toe, right?

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And my EHL, at least what I

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have of it, looks pretty good.

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But my tibialis anterior, which should be

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one pretty robust, black tendon, it's not.

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It's irregular.

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It's separated into pieces.

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It inserts on the tibialis anterior as one

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of its main insertions, but not its only one.

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It also has a small fascicle to

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the base of the first metatarsal.

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But look at how abnormal it is.

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Looks pretty good.

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I'm focusing on the proton density,

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spur, stir, spare, or special.

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Looks a little worse, looks a lot

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worse, looks a lot worse, split into

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two, split into two, and too big.

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It looks like mashed potatoes.

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It's still split into two, starting to come

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back together, starting to come back together.

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It is back together.

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Well, almost back together.

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Still a little bit delaminated.

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But all the while, on the T2, which is highly

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insensitive for subacute to chronic abnormalities,

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it looks pretty darn black, doesn't it?

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It's not until you get to the really

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worst portion down low where you start

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to get an inkling that something's wrong.

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So do not use the T2-weighted

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image for diagnostic sensitivity.

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That is not what it's for, even

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though it's a water-weighted image.

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Now the T1, it does a pretty good job.

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It doesn't tell you really what the tissue

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is, but it tells you that the tendon is

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buried in some amorphous inflammatory

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tissue and has an inappropriate,

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irregular, non-oval, non-round shape.

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It also does a terrific job at showing

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you the shape and configuration

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of the bones to which it attaches.

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Which is one of its great strengths.

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So, we don't have a posterior tibial tendon tear,

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but we do have an unexpected anterior tibial

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tendon tear, and we've excluded an extensor

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hallucis longus tear, which is very important.

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Now while we're at it, since they were worried

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about the posterior tibial tendon, we look

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at the character of the bone, we see that

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the navicular is a simple navicular. There's

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no accessory navicular or os tibiale externum

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in the posterior tibial tendon, or a type

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2 accessory navicular with a cartilaginous

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synchondrosis or an arcuate navicular.

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So we've excluded some of the

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main anomalies that occur here.

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There really aren't any anomalies that

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occur back here on the back or dorsum

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other than some spurs that can get in

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the way, which this patient doesn't have.

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So we have proven that there

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is a tendinous abnormality.

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But I like to go around in a circle, right?

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I'm a, I'm a simple kind of guy.

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And I like to check out my Achilles,

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which, number one, there's only one

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tendon back there, so that's pretty easy.

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Then there are three tendons over here.

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We've done that.

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So we should go one, two, two tendons

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over here on the lateral side.

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Let's check those out and see how they're doing.

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The peroneus longus is doing very well.

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The peroneus brevis?

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Well, not so much.

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It's got this small, but definite

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tear in it that wants to perforate and

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split the tendon, which it often does.

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That's usually the kind of

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tear you get with a brevis.

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The brevis is kind of like this.

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It splits in the middle, and then it

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usually separates into two almost arrow-like

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structures that drape over. I'll draw it in

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orange, that drape over the peroneus longus.

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Okay.

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It's starting to want to drape over the

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peroneus longus, but it hasn't done so yet.

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There's our slightly thickened,

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irregular calcaneofibular ligament.

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So we definitely have a tear of our

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peroneus brevis, the lateral aspect.

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Let's troll it, or let's scroll it.

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It starts to look a little better when we get to

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the retrofibular region, but it does flatten out.

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Now the most common cause, for missing

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a peroneus brevis tear, besides the fact

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that nobody directed you there, is you

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have acquired the study incorrectly.

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So, here's our brevis coming down in the

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sagittal projection, and you did this.

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When you should have done this,

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always perpendicular to that tendon.

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And did our team do that?

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They sure did.

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Let's put up a sagittal.

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Let's see where we are.

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They're oblique.

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They stay perpendicular to the tendon.

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And that is why you, and I, are here.

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In the reading room, we're able to

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pick out this peroneus brevis tendon.

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So, let's keep going, shall we?

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We said that we checked out 1, the Achilles.

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2, peroneus longus and brevis.

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3, the medial flexors.

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Tom, Dick, and Harry.

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And 4, we found a tear in the tibialis anterior.

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We confirmed that the longus was normal.

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And we see a little bit of swelling,

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but otherwise, pretty normal looking.

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Peroneus, tertius, and extensor digitorum.

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So, we're done with the intrinsic tendons.

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But we're not done with our search pattern

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and the axial projection, because we have

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established that there are two tendons diseased.

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So how about the anterior retinaculum, also

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known as the anterior inferior retinaculum, or

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extensor retinaculum, below the ankle joint?

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Is it ruptured?

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Well, if it was ruptured, it would roll up

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into a ball, but it certainly has thickened.

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And that's not unexpected, considering

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the structure right under it is sick.

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What about the lateral retinaculum?

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This one's a lot more important, because this

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one secures via a small little thorn that's

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fibrocartilaginous like, right, right here.

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Let's see if I can get my

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magnifying glass to work.

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Right there.

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That little thorn.

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Connects directly, the tip of it connects

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directly to the retinaculum, and guess what?

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The retinaculum is not connecting

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to its tip, it's on top of it.

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That should be attached to that.

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So the retinaculum, which is too gray

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and slightly thickened, is stripped.

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Which place, places this peroneus brevis

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and longus at risk for future damage.

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Now let me show you a real wow.

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Let me show you what a massive

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peroneus brevis split tear looks like.

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But one more caveat before I do.

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When you're looking at the peroneus

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longus and brevis, don't forget to

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inspect the retrofibular groove.

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It should be convex forward

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most of the time, about 82%.

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It's flat about 11%, it's convex back 7 percent

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of the time, it should be smooth, make sure you

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check for spurs, which predispose to a tear.

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Now let's look at the GOAT, the greatest

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of all time, peroneus brevis tears.

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Here it comes.