Interactive Transcript
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So this case is a 29-year-old man.
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The provided history was that he, um,
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was a professional football player and had proximal fibular
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and ankle fractures.
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Um, with that history, even without looking at the imaging,
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I think we're thinking is the proximal fibular fracture a
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mazen nerve type fracture
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and maybe there's an unstable ankle injury resulting from a
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pronation external rotation type mechanism.
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So we wanna confirm that our clinicians did not lie to us
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and that there truly are fractures.
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So looking at the bones, we can see there is this fracture
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of the posterior malleolus.
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Um, right here, there's some edema related to the fracture.
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So we can, um, guess that this fracture is recent.
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As we scroll further distally, um,
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you can see some bony irregularity, little osci at the tip
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of the medial malleolus and distal fibula.
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At these, um, sites of bon irregular tn ossicles,
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I don't see a lot of edema,
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so it's not clear if these are related to the recent injury
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or from a preexisting injury.
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Um, so now that we've looked at the bones,
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let's turn our attention to the ligamentous structures.
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So going to our posterior malleolar fracture, we can see
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that this involves that volkman fragment or tubercle,
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and so it's at the attachment
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of the posterior inferior tibial fibular ligament.
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If we look anteriorly,
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the anterior inferior tibial fibular ligament also looks
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disrupted irregular fluid signal in the structure,
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um, clearly abnormal.
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As we come a little further inferiorly, we can see that
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that additional structure, um, that's a little more inferior
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and deep to the posterior inferior tibial fli lament.
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That inferior transverse ligament also looks, um, injured.
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Going to our coronal plane, you can see
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that more triangular structure,
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our posterior inferior tibular tibial fibular ligament,
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that more horizontal structure,
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our inferior transverse ligament looks like
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that inferior transverse ligament is also attaching to, um,
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a non-displaced bone fragment.
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There on our coronal images, um,
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we can see that interosseous ligament,
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but if we look back, cross-referenced to our axial images,
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it's not clear to me that
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that interosseous ligament ever truly attaches to the tibia.
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So I think that's probably injured as well.
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Um, quite a bit of edema within that syndesmotic space
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and more proximally that, um,
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syndesmotic membrane also looks a little irregular,
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though we're getting kind of to the periphery,
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so we're losing signal a bit, um,
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at this more proximal portion.
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So all of these findings together compatible with
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as syndesmotic injury, that high ankle sprain, uh,
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much less common than your typical low lateral ankle
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ligament injuries.
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Only about 1% of all of your ankle injuries.
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Um, and interestingly, that injury
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to the posterior inferior tibial fibular ligament has
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specifically been reported to be associated
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with a longer period of disability
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in professional football players.
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So this person probably gonna take a little while to heal.
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Uh, syndesmotic injuries are often gonna be associated
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with other ankle injuries.
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So if we turn our attention
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to the low lateral ankle ligaments, you'll see
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that your anterior talo fibular ligament also torn,
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um, posterior talo fibular ligament.
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Um, again, emus, irregular, partially torn.
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And then looking at our calcan fibular ligament, um,
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a little bit thickened, so possibly from old injury,
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but there is some increased signal in the ligament near
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the calcaneal attachment.
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If we turn medially, we can see
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that our superficial deltoid ligaments are, um,
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stripped from the medial malleolus.
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Actually, it looks like on our coronal images,
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that the torn fibers are kind of redundant
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and now interposed in the expected location
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of our deep deltoid ligaments, which are also torn.
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Um, so putting it all together,
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thinking about those concepts of the greater
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and lesser rings, um, that Dr.
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Resnick introduced in his talk on the ligaments.
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So we're thinking about the greater ring.
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It looks like there are at least three breaks.
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Our deltoid ligaments medially,
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our lateral ankle ligaments laterally,
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and then our syndesmotic ligaments.
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So that's an unstable ankle injury right there.
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And then thinking about our lesser ring,
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we have a quadruple break.
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So the anterior
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and posterior inferior tibial fibrillary ligaments,
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our interosseous ligament,
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and then also our inferior transverse ligament.
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So there's total tibial fibular instability here.
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Um, so thinking about the bones one more time, we did see
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that posterior malleolar fracture,
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but when you see a syndesmotic injury, what you wanna do is
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also carefully inspect your tail art dome
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and your tibial, hon.
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Because these high ankle sprains are also associated
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with osteochondral injuries,
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you'll get bone contusions elsewhere, um, in
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the ankle as well.
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And then you wanna inspect that tibial fibular joint
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for incongruity.
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In this case, I think he's actually fairly well aligned.
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Not much displacement or distraction here.
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Um, but those are associated findings in the setting
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of syn asmatic injury that you wanna be careful to look for.