Interactive Transcript
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So I'm here with Dr. Stern.
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3 00:00:01,670 --> 00:00:03,650 We're looking at a 14-year-old man who fell
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and now has snuffbox radial tenderness.
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And we've got a coronal T1.
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It looks like we're not in the plane
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of the scaphoid, but we actually are.
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It's just the scaphoid is edematous.
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We've got a coronal water-sensitive PD spur.
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The detection sequence on the left
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is the characterization sequence.
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And then we have on the right a 3D
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GRE, which is not so good in the bone.
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You can see how difficult it is to spot the edema.
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Or this little fracture line right here,
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or a slightly bigger fracture line.
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And, um, that's one reason why we don't
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use gradient echo for medullary bone.
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Um, one quick comment before we talk
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about the management of this case.
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The way this case was done.
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Probably a good teaching point in the
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improper way to evaluate the scaphoid.
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You know, they did a coronal, and
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then they went ahead and did a straight axial.
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And then off that straight axial,
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they did a straight sagittal.
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And a lot of my hand surgery friends
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frown on that technique, and the more sophisticated
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the surgeon, the more they want a parallel
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view, a perfectly tangent view to the scaphoid.
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So the way to get that is to do what I
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call a para-axial or a para-sagittal
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down the long axis of the scaphoid.
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Then you'll have something that looks like this.
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You'll see the scaphoid in that orientation.
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Then you hit it again with another oblique, and
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now you'll have the scaphoid in absolute profile.
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And this is a good way to do it, both on
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CT and MRI, and you will, you will have
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a happy clinician and happy surgeon.
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Wasn't done here.
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We still have the information we need, which is
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a microtrabecular injury of the scaphoid bone.
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So, the scaphoid, Let's scroll it, and
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I'm gonna blow this up a little more so
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you can see the scaphoid really well.
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And now you can kinda see these little micro
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trabecular lines creeping around the scaphoid.
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Alright.
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Surrounded by ill-defined edema.
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And then, on the next cut, you can actually see
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a linear fracture line that's intramedullary.
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There's no cortical step off.
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And there's plenty of edema to go around,
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but it doesn't go all the way through.
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So, we want to define what kind of fracture we have.
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Is it an enchondral bone, medullary
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bone, spongy bone fracture?
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Is it transcortical?
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Is there a step off?
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Does it go part of the way across?
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Does it go all the way across?
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Is it waist?
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Is it proximal?
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All the, all these things matter, uh, in terms of
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the management of the patient and the potential, uh,
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future complication risks such as avascular necrosis.
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And then one other comment before I turn it over to Dr.
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Stern.
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I like to, to grade my bone injuries.
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And this is just how I do it.
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So the earliest grade of bone
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injury is simply a contusion.
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I'm just gonna number them.
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Uh, just to give you some orientation.
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So a low-grade contusion, LGC, that would
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just be on the most sensitive sequence.
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You just see a little bit of edema, or you
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see some edema, but the T1 looks normal.
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Now that's not the case here.
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The T1 isn't normal in a, in a, what
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I call a stage two or the next level up.
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We have a high-grade contusion.
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So we have the same exact thing, except
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this time, edema here, and edema here.
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But you don't see any lines.
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Then in the next step, you have what I call a
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type of microtrabecular injury, of which all of
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these are, that I would call a microtrabecular
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fracture, or a so-called hairline fracture,
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which we've used culturally over the years.
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And that's when you have, we'll call
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this a microtrabecular fracture.
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And that's when you have these little lines,
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but no step off and no transcortical violation.
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Then you start to get into higher grades of injury,
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macro fractures, displacement, angulation, and all
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the stuff we know from conventional radiographs.
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And that's usually the progression.
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Now we're talking about acute injuries,
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we're not talking about repetitive trauma,
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like stress or insufficiency-type fractures.
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So now, what do you do with a youngster like
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this, where you have what I would consider a
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lower grade injury? I think the plain film,
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even though we don't have it, it
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would be normal in a case like this.
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You've been very articulate in describing this,
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and I think, uh, in my management of patients
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with snuffbox tenderness, the MR has made a quantum
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difference in my therapeutic recommendations.
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Uh, specifically, uh, in this case, uh, I think the,
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uh, integrity of the scaphoid is perfectly intact.
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And, uh, I do not think that, uh, operative
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fixation, uh, of any type, uh, would be indicated.
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I would treat this in a cast, uh, and
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anticipate over time, uh, six weeks to,
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six to ten weeks, uh, particularly being,
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uh, an adolescent, that this would heal.
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The, the really difficult decisions for hand
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surgeons, who are, of course, Orthopedic
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surgeons, of course, are biased, is if there's a
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complete fracture line, even if it's non-displaced.
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So the big issue in my field is, how do you
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manage a non-displaced fracture of the scaphoid?
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We know that if a non-displaced
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fracture is treated non-operatively in
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a thumb spica cast, it is going to heal,
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uh, probably 90% to 95% of the time.
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We also know that if you do surgery, there's
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always risks of, uh, complications from infection
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to hardware issues, et cetera, et cetera.
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I think the tendency today for non-displaced complete
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fractures, the high grade, almost macro injury,
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as you described it, would be to internally fix
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it because it heals
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more quickly and there's a more rapid
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return to play, so, uh, but certainly it's
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acceptable, for example, in Great Britain, the
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Brits are a little more conservative with that
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type of injury, again, non-displaced, completely
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non-displaced fracture, but they may
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very well treat it in a cast, thumb spica cast.
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Whereas I think in the States, there would
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be more of a tendency to do some type of, uh,
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headless compression screw internal fixation.
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Now, I've heard the term Herbert
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screw, a modified Herbert screw.
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Are there different types of
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screws that you put in there?
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What's the You know, too many to choose from.
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Yeah, lots
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and lots of choices.
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I think they all basically do the same thing.
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They're internally stabilizing the bone and
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providing some degree of compression to the bone.
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I just want to make one other point.
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And this is really relevant
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for healing, especially on CT.
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But you can see the technologist
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did a straight orthogonal.
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And now that I've lived in the hand surgery world
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for a quarter of a century, I've learned from them.
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What they need and why they need it.
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And for instance, if you look at even, even the
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orthogonal sagittal, the fracture line looks
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a little deeper than it does in the coronal.
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Here on the coronal projection, it looks
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like it's only about 50 percent depth.
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Now you go to the sagittal, it would have been nice
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to have a parasagittal right down the long axis.
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You can see that even though the line doesn't go
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transcortical, it does go more than 50 percent across.
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So, you know, you've really got to kind of
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weigh and look at every single projection.
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Now when we're talking healing,
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we actually have a fracture without
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displacement, but a cortical step-off.
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We use 50 percent bridging on CT to
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decide whether a person returns to play.
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Uh, have you ever used that number?
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Uh, because I know I've given it to you in the past.
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Well,
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it's, no, actually, uh, that's
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kind of been your number.
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And it's, uh, it's, uh, it's now in the literature, so.
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Again, there's some subjectivity to what 50
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percent is, but I think in general, uh, if the
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radiologist tells you that there's 50 percent
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healing, with a fair degree of certainty, you
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can let that individual return to play with or
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without some kind of, uh, protective splint.
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One
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other bit of clarity and then I'll log off.
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When we're talking 50%, we don't just look at
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one cut and say, okay, that's 50 percent across.
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We do it by volume.
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So we go all the way from front to back,
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we look in the sagittal, and we make sure
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that we're talking about a volumetric 50%,
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not a single area 50 percent on one slice.
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Let's move on, shall we?
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Yeah.
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Thank you.
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Sure.
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Dr. P and Dr. Stern out.
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