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Scaphoid angles and wrist imaging.

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Simple?

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Well, not so much.

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We've got a coronal water-weighted

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image on the viewer's left.

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And instead of having a straight sagittal, as

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you've seen with some of the sequence analysis, our

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sagittal is along the long axis of the scaphoid.

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And here we've displayed it with a

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sagittal, fat-weighted, T1-weighted image.

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And there's a fracture through and

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through, transgressing the cortex.

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Now you'll notice this black line that is

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parallel to the long axis of the scaphoid.

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That black line tells a story that

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perhaps is better told with a CT scan.

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Let's have a look.

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So here is a CT scan with a coronal projection using 0.5

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20 00:01:03,415 --> 00:01:08,454 or 0.6 millimeter slice thickness with 50 overlap so that

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the edge detail and intramedullary bone character

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is well seen and you might then form an axial off

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this coronal in the direct orthogonal projection.

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But for the scaphoid, which has a screw, a compression

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screw inside it, that's not really what we're after.

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The clinician wants to know, medullary

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character of bone, where is the screw?

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They want to see the entire long axis

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of the scaphoid, all at the same time.

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They want everything.

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Dogs and cats living together, 10 days of darkness,

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the plague, mass hysteria, they want it all.

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They want the edges of the

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cortex, and I don't blame them.

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This is a complicated area with important

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consequences if you get it wrong.

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We're looking for screw position.

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We're looking for medullary bone character, and

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we're looking for fracture healing, which we

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want to see at least 50 percent of the volume.

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of that bone bridged.

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When I say bridged, I mean both

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cortical and medullary bone bridging.

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So we take our coronal and we form a

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sagittal oblique through that coronal.

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That will then look like this.

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That sagittal oblique looks more like an axial oblique.

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By the way, there's a crack still in this scaphoid.

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It was difficult to see in the other projections.

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There, somewhat on Foss, or in its long axis

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projection, is our compression screw, properly

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positioned, wholly intramedullary, but not

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yet transgressing the site of the fracture.

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Oh, but we're not done yet.

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There's more obliques to be had.

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This is like an oblique soup.

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So from this oblique, we take another

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long axis oblique, and we come up with

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something that looks rather sagittal, not

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an orthogonal sagittal, an oblique sagittal.

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And now, we see that our screw is properly positioned.

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That it does transgress our fracture.

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Our fracture is not completely bridged.

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There's an area of lucency.

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There's still a tiny crack present.

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And the dorsal aspect of the

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scaphoid is beginning to sclerose.

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And/or bridge, so at least 30 percent on this

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one slice of a very large acquisition is bridged.

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And we're gonna want to look at every single

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slice to get a feel, not for the area of

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bridging, but for the volume of bridging.

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But remember, we're in an oblique soup, a storm

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of obliquity, so another oblique is to be had.

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And that finally gets us to

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the ultimate, the penultimate.

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Thanks for watching!

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Scaphoid view that shows the entire structure on

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Foss, the screw position, and the fact that actually

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most of the distal aspect of the scaphoid is bridged.

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You are being shown only one cut of multiple

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slices, and in fact on many of those other

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slices, there was bridging of both medullary

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bone, but especially of cortical bone.

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Yes, there's a little bit of irregularity

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along this mesial aspect of the scaphoid,

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but this is a pretty darn good result.

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And over time, this medullary bone will fill in.

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The soup of obliquity.

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Multiple oblique planes prescribed for you in order

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to get you, on either CT or MRI, where you

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need to be to see fracture healing greater

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than 50%, the position of the screw, the

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conformity and/or deformity of the scaphoid.