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This is a 55-year-old woman with posterior tibial

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tendon dysfunction, the sensation of instability,

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and they want to know if there's a rupture.

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They obviously suspect that there is a tear.

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So I have before you three sequences, a proton

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density fat suppression detection, a T2 for

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qualification of the age, and activity of the

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tear, and the T1 as my basic, basic sequence.

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So within the tendon, which is

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hypertrophic, as most of these tears

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are, there's a signal, it's gray.

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On T2, it's less conspicuous,

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suggestive of chronicity.

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And on the PD, it's detected as a tear

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that's irregular, and involves almost 50

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percent of the cross-sectional area of

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this markedly enlarged hypertrophic tendon.

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And we're going to scroll it in a minute,

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but before we do, let's re-emphasize

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the way we want to image this tear.

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We want to look at the peroneus, sorry,

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we want to look at the posterior tibial

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tendon, as it comes down to the navicular,

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and we want to make sure that our sections

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are perpendicular to the PT tendon.

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We want to follow it all the way down.

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We also want to go back and forth between

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our water-weighted, our T2-weighted, and

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our T1-weighted sequences as we scroll.

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And while we said earlier the T2

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weighted image was unimpressive,

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suddenly it becomes very impressive.

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Which means there's a hole, there's

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a gap, there's a cyst in that tendon.

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So it further elevates the diagnosis to one in

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which the patient is at risk of a massive rupture.

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They haven't done it yet,

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but it's like a wailing tear.

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She's about to blow.

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And we also have another finding.

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The site of weakness in this patient

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is related to the remodeling of the

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groove that this structure exists in.

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Look at the little spur that's

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projecting off to the side.

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That is one potential area of weakness.

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Look at how dysplastic that groove is, and our

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tendon is filled with blood and fluid on even

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the T2, which is normally not that sensitive.

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Let me move my structure in a little

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bit so you can see it a little better.

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And we're going to keep following it.

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Look at how it balloons out

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into its hypertrophic state.

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Let me move the T1 over a little bit.

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And then it becomes black

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again, which is the norm.

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Normally it re-opposes and looks a

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lot better as it begins to insert on

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the navicular, which is pretty smooth.

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Here are some of the other

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fascicles going off to insert.

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on metatarsals and cuneiforms.

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So we go back, it gets hypertrophic,

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and then we start to see the tear in

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the typical inframalleolar position.

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Usually patients like this, because they've

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lost the ability to invert, the evertors

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pull on the foot and will produce tremendous

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stress on the spring ligament, causing it to

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thicken, as we see here, and maybe even rupture.

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It has not yet ruptured.

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Now when I'm describing these abnormalities

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to clinicians, I want to give them a length,

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which I can do in the sagittal projection.

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There's the bottom, there's

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the top, and I'll measure it.

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I'll also describe to the clinician

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whether it's insertional, not.

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Inframalleolar, yes.

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Retromalleolar, yes.

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Supramalleolar, yes.

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Myotendinous, no.

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So I will systematically go through from high to

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low, or low to high, where that tendon is located.

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What's its character, is it hypertrophic,

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what is the percent of involvement, and I will

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give them a measurement for length, and the

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status of the spring ligament, and the status

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of the navicular and any navicular anomalies.

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That's the checklist.