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This is a 15 year old man with unsighted elbow pain after a hyperextension

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injury four to five weeks ago.

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Evaluate for ligamentous tear.

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So I like to start my elbow images and assessment in the coronal

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projection unless I'm looking for a mass. So the ankle,

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I like to start in the sagittal projection in the elbow.

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I like to start in the Corona projection because I'm frequently looking at

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athletes who might have radio Capella lac,

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who might have a medial or lateral collateral ligamentous injury.

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And I get that information quite nicely in the Corona projection.

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I'm also very used to it from AP radiographs.

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And one thing I really like to do in all my joints,

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but especially in the elbow, is assess the elbow hinge.

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I wanna see that there's conformity.

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There is a best fit scenario between the alna,

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the sublime cubicle, the radius, and the humus,

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which should exhibit three bumps and two

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depressions. So five moguls, if you will.

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1, 2, 3, 4, and five.

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So let's keep scrolling in the coronal projection,

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and I'm gonna give you a third coronal.

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The first two are three millimeter sections, proton density,

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fat suppression, and the middle is a t1.

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And on the far right is A three D, 1.5 millimeter,

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G r e or gradient echo, known as additive gradient, echo or adage.

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All right, let's take our polling question now.

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Which of the following is true?

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The posterior and transverse components of the UCL are the main stabilizers, a,

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B, patient as sloppy hinge syndrome C.

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The anterior bundle of the UCL is a VST from its origin without bone D

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avulsion injuries of the UCL with bone or more common in children E.

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The distal attachment of the UCL is torn. The correct answer is D,

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evulsion. Injuries of the UCL with bone are more common in children.

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Let's go through these one by one.

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The posterior and transverse components of the ucl. First of all,

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those are not major stabilizers.

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They're best seen in the axial projection. Let's blow it up.

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Here's the posterior and transverse component of the ucl.

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They are minor contributors to elbow stabilization. There's your ulner nerve,

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so that would be absolutely false.

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The main contributor is the anterior bundle of the ucl,

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which is right here. Patient has sloppy HI syndrome.

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Very uncommon in children, unless they have radio Capella,

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LAC or Oticon decans, they usually have a smooth,

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best fit scenario between the radius, the Capella Thero, and the Alna.

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Everything is nice and smooth and fits together beautifully.

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There is no sloppy hidden syndrome now in the elbow. Very unforgiving joint.

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The joint with the smallest capsule, the elbow,

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the joint with the tightest capsule, the elbow,

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the joint with the least room for error for deformity elbow.

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So when you have minor deformities, minor spurs, small bodies,

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you get locking early on. C,

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the anterior bundle of the UCL is a VST from its origin without bone.

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That is not correct. That is cortex.

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You've gotta get your eye to trace that cortex.

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The proximal anterior bundle of ucl,

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which is the main stabilizer of the elbow, is fanned proximally.

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That's okay. It's even more obvious cuz it's swollen.

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It's swollen cuz there's an evulsion fracture.

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You know there's an evulsion fracture cuz you've lost the cortex and there's

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edema underneath the area of evulsion.

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It's too linear to be the free edges of a ligament.

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Let's take a look at the t1. I'm gonna close now. Let's take a look at the t1.

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That is a fragment of cortical bone. That's pretty tough.

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But you have to ask yourself, what is that thing on the gradient echo?

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This is something you always have to query in a child because children

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are more likely to AULs bones than to tear ligaments in many instances.

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Cause the attachment is weaker than the ligament itself,

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which is very resilient.

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Now another critical teaching component of this case is the distal

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ucl, which is a very common locust for UCL injuries.

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Lower intermediate grade, especially in throwers, in overhead athletes.

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These patients have had some type of valgus event.

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So I like to look at this area and I wanna see it be

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conical,

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a little bit rounded and smooth and no more than two millimeters in depth.

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So how would I measure this depth? Blow it up, get my little ruler.

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I would never measure it, but I'll measure it for you.

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You can see it's about 1.8 millimeters. That's okay.

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There's some cartilage in there too,

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but I don't wanna see this tissue stripped away.

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I don't wanna see fluid interposed here between the ligament and the sublime

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tubal of the ulna, which is a commonly missed abnormality.

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Just for completeness, let's put up our sagittal.

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The patient had a hyperextension injury and there's a good reason to put up the

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sagittal because theon could potentially be injured. Now,

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when you extend your elbow, if you're at home or at work, put your arm out.

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When you extend your elbow, where do you feel it? On the inside, right?

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Because you have a six to eight degree valgus carrying angle.

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So when you hyperextend,

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you're going to put stress on the inside of the elbow and compression on the

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outside of the elbow.

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So you can tear or AULs the U C L from the simple act of

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hyperextension.

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You can also fracture theon from the simple act of hyperextension.

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This patient did not.

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For those of you radiographers out there,

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I know you remember that there are certain ossification centers that can be

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multiple. The elau is famous for this and so is,

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so is the lateral. So is the tral also famous for this?

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The lateral epicondial can also be multiple. Now there's another finding here,

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and I'm gonna scroll for a minute and see if you pick up on it,

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it's on your left. It's on the proton density, fat suppression image.

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It's also on the t1.

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Some of you might have noticed that the hypothesis is a little

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bit gray right there and it's a little bit bright right there.

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What does that mean?

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That means that the patient has an sitis.

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So this patient likely had a preexisting micro instability or

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overuse syndrome where there is micro mobility of the

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medial epicondial giving it edema,

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and then the child had a superimposed trauma on top of that. Now,

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it'd be very hard to say that that is not an acute EMIS pattern from

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the injury itself, but at least it makes you think about it.

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And you go over to the gradient echo and you look at the joint right here and

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make sure that the joint is nice and smooth. Not the joint,

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but the interface between the hypothesis and the bone is normal and it is.

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So what's the treatment for this rest? This is a fracture.

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This is gonna heal without a pin because it's so close to its original locust.