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This is a ten-year-old girl who has a "fracture."

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3 00:00:06,740 --> 00:00:08,730 And she's got a midfoot abnormality.

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You've got a long axis; it's actually

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a short axis, but you're seeing the

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foot in a long direction view of

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the cuneiforms and the metatarsals.

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And you are struck by how much edema

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there is at the tarsometatarsal

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junction and all these fractures.

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Like, like this one here, and that one at

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the base of the third, and this one at the

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base of the fourth, and this one a micro

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trabecular fracture at the recessed base of

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the second, at its junction with the cuneiform.

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And that is normal; this recession here, to

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help support the Roman arch of the cuneiform.

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Foot.

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So I wanna talk to you a little bit

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about classifying this injury, which is a

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Lisfranc, not a sprain; a Lisfranc ligament

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rupture that is the stump of the ligament.

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That little nubbin of dark signal is a little

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bit of blood that is the other stump of the

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ligament, so the proper ligament does not retract.

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Furthermore, she has also

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injured the plantar ligaments.

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This is the stub of the C

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one M two plantar ligament.

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Should have gone to the base of the

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second, and here is the squiggly,

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wiggly end of the C1M3 ligament.

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It should have gone over to the

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base of the fractured third.

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It did not.

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But let's talk about classifying this injury.

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The typical classification describes

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Homolateral, where all the metatarsals

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move together in one direction.

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Divergent, where the first goes

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this way and everything else stays

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the same or moves a little bit.

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And then isolated, where maybe one or two

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metatarsals move relative to the cuneiforms.

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In this case, we're gonna have to go

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with another classification system,

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because none of these really apply here.

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And let's go with a visual

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radiographic classification system,

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that of Nunley and Bertullo.

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So in stage 1 injuries, this represents

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a low-grade sprained and less frank

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ligament complex, a dorsal capsular

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injury, a dorsal ligamentous injury, but

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the proper ligament is usually preserved.

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On x-ray, there's no diastasis, there's

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no displacement, there's no separation

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between the base of C1 and C2.

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or C1 and the base of M2.

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There's also, in the axial projection, there's

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no collapse or loss of the Lisfranc arch.

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In other words, these bones don't

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start to fall forward or start to

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fall into a plantar orientation.

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At bone scintigraphy, one sees increased

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tracer uptake often throughout the

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metatarsal junction stage two injuries.

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These demonstrate about a two to five millimeter

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area of diastasis between C1 and the base

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of M2, but the arch, again, is preserved.

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Let's measure it.

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Let's see what we got.

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Let's look at the base of C2.

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M1, sorry.

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The base of C1 to M2.

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I apologize.

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And it's four millimeters, so

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right smack dab in the middle.

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Stage two.

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So this is a stage two, two to five millimeters

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of diastasis between C1 and M2.

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In stage three injuries, you've got a

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greater than five millimeter area of

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displacement at this interval, and then the

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arch is gonna start to fall or collapse.

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So let's have a look at that arch.

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Here is the arch, and let's have a look

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at the region of the Lisfranc ligament.

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Here are some.

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Intracuneiform ligaments; they're

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black, they touch each side, that

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is not a healthy ligament at all.

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It's a grey ball of fluff.

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It's blood; it's swelling;

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it's rolled up ligament.

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But this isn't the direction where I

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would typically go after the ligament.

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It would be the long-axis view,

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which is actually a paraxial.

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But you can see, very subtly,

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look at the slight twist.

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Look at the slight axis turn of

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this bone in the middle column.

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It looks like it's turning

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slightly counterclockwise.

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Look at the top of it.

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It looks like it's just starting to

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sag down a little bit, doesn't it?

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So these are some of the earliest, most subtle

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manifestations of arch collapse, but we would

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characterize this as a stage two Nunley and

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Vertullo type of Lisfranc tear or sprain.

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And I have a nice table to display at the end of

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this for your perusal and educational interest.