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Our next series of cases are in the setting of

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trauma.

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So this patient came in with polytrauma, and normally, I think you would

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have seen up until now, we acquire everything from the abdomen pelvis down to the

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feet. Very rarely we do unilateral examinations, which is

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what happened in this patient. We're only imaging their left lower extremity

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because they're a young patient who doesn't otherwise have any

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morbidities, and they're coming in with

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significant trauma burden in just that one lower extremity.

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So as we're scrolling down, we can see that there's

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a patent common iliac, external iliac, and internal...

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external and internal iliac artery system on both sides, and we're really going to

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focus just on that left side with a patent superficial femoral

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artery going all the way inferiorly.

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But before I do that, we're actually going to

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stop after we look at that popliteal artery, and we're going to focus looking at

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the soft tissues. Up until now, we haven't talked much about

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looking at the soft tissues, but it's really critical when we're looking

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at the lower extremity arteries to also pay attention because they can give clues.

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A lot of the times these patients present with osteomyelitis, so it's important to

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look at your bone windows and make sure there's no osteomyelitis, no cortical

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erosions. In a patient of trauma like this one, we want to make

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sure we describe the burden of soft tissue

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trauma. So over here you can see that there's basically a defect along their whole

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posterior calf, and you barely see a skin and subcutaneous tissue.

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Their bones are also broken, so there's a compound fracture right here.

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You can see how angulated and displaced this tibial fracture

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is. That bone fragment is really just protruding outward

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into the air, and there's also a fibular

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fracture right here. So we're going to look at that fibula fracture

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right here, which is angulated and displaced.

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Coming back to the arteries, though.

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So now that we know this person has had a significant amount of

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trauma, we have that compound fracture of the tibia, the fibula, we

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have all this air fossae, lots of soft tissue

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defects. Really, this muscle is entirely bulging.

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There's no skin over here. And focusing back

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on our arteries here, the popliteal artery is patent and it gives

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rise to the anterior tibial, which is patent.

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The tibial peroneal trunk was patent.

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Peroneal artery is patent, and as we're following it down, while the

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anterior tibial and peroneal remain patent, we lose the

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posterior tibial artery and it's occluded.

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So it never really comes back, but we see that anterior tibial and the

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peroneal artery supplying everything

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all the way up until that distal calf.

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As we move on, right at the ankle is when we start

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seeing that posterior tibial artery again, which then forms the plantar

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arteries. And really at the level of the plantar arteries, that posterior tibial

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artery is reconstituted. There is thrombosis of that

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posterior tibial artery in the setting of trauma, so traumatic injury

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of the artery. Other ways an

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arterial injury can present is basically a transection or a dissection,

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and all of that would have... a dissection would have an appearance of a flap

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within, just like we've seen previously.

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And sometimes, it would

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be extremely hard to differentiate a thrombus versus a

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dissection flap within, just because of the small caliber of vessel, and especially

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if it's completely obstructive.