Adequacy of the lateral cervical spine X-ray Dr. Mahadevan from Stanford School of Medicine explains adequacy for lateral cervical (neck) x-rays
Adequacy of the lateral cervical spine X-ray
- We're going to look at some radiographs of the cervical spine of the neck and try to determine whether they're adequate or not.
- What does it mean to be adequate? When you have an adequate view, you can see from the first
- vertebrae all the way down to the junction of the seventh cervical vertebra and the first thoracic vertebrae.
- I see. We call it adequate because it's adequate to make a diagnosis. That's right.
- You want to see the entire cervical spine so that you can make sure that there is not an injury there.
- So what are we looking at? What are we directly staring at here? We are looking at the lateral which shows
- essentially part of the cervical spine. It shows cervical vertebra one through five. I see.
- Just to make myself clear, these are both lateral x-rays--meaning x-rays from the side of a person. That's right.
- If I know my anatomy, this person is facing this way. They're actually facing the other way.
- Oh, I can see, and there's a little jaw. Okay, I was just testing you. Good job.
- Alright, so the person is facing that way. This way is the front. And you were counting the different bones.
- Exactly. You were saying this is one, two, three, four, five. That's why you hear people with back
- injuries saying they have problems in what do they call it? L5. Yes, exactly. Actually we count even
- further forward from there, and we look at exactly at those things that kind of look like squares.
- Those are the actual vertebra. Exactly, right there. Exactly. Although we're interested in the entire spine,
- we kind of go down. You can see if you look at the fifth square there; below that it's really hard to
- see the squares of six and seven. Right, we can't see anything below that. It looks like this person's
- shoulder is blocking it. Exactly. You can see that that big white thing there is the person's shoulder
- has gotten in the way. They shouldn't have worn those lead shoulder pads. (laughter). It's making
- it hard to see if there's something going on down there. So how do you solve that? If you look over
- at the other film, it's what we call a swimmer's view. We ask the patient to raise one arm and lower the other.
- In doing so, you clear that lower cervical spine and allow better visualization of the entire
- spine. I see. And you're taking it from the direction of the raised arm. You take from the side.
- And you can see . . . this is the raised arm here, and the other arm on the further side of the patient
- is down. That allows us to get the should in position so that it doesn't block like this one does over here.
- It's also clearer that this person is facing in this direction. (laughter) So let me see if
- we can count. So this is number one. Yes, that's one. One, two, three, four, five, six, and there
- we already got to six. We didn't see six over here, and then we've got seven. So you would call this
- an adequate view of the neck because now we can look all the way through seven.
- Absolutely, we can get all the way down to seven. And ideally you want to see the top of one.
- Actually, in this counting system we go one through seven. And then we start back at one again
- because we're starting with the thoracic vertebra. Oh, it's like those streets where they start numbering
- where it comes one again. Did I number that right? You did. Again, we're looking more to the
- front. You've got your numbers perfectly on every spinous process. The little bump that you can feel
- when you press on the back of the neck. But we're really more interested in the alignment of the front
- of the vertebral body. Okay, so this is one, two, three, four, five, six, and seven. You want to look
- at the top of one. If you just continue down right there, sometimes it's difficult to see.
- But exactly you want to see if there's an alignment right in front. There's something right here that I cannot really see,
- but you're an expert, so maybe you see things that I don't. (laughter) What do we so with
- this. We've shown you that you can get a swimmer's view, and it can show you all the way down to c7 and t1.
- But on the orginal view as you've shown, you can't see that. So what we did for this patient
- was get a swimmer's view. I see, so it's adequate. We have this other slide right over here.
- Why is this one interesting? This is the same patient, and now we've taken that same view that we talked about before.
- I mean the swimmer's view. This is the same patient as this patient right here, not this patient over on the right. That one looked pretty healthy. Exactly.
- But here's an abnormal swimmer's view. The same person as this one, not the other one.
- Facing in the same direction in case you want to test me. (chuckle) Okay, good. If you count again, starting with the first vertebra
- One, two, three. Three's this one here. I see this whole things three right here. Four, five, six,
- and then seven if I see that properly. (It's a little dark there.) Absolutely, the key important
- finding there is that as you draw a line along the anterior (or the front) of all those vertebral bodies
- if you were to connect them. Right. Just like that. I'll draw a dotted line. Fantastic. And as you
- go down. Oh, look at that--seven as it looks like there's a little of a disruption there. Exactly,
- and it's pushed back. And the problem is right behind those bones is your spinal cord. So, any kind
- of injury like this can potentially injure your spinal cord and lead to permanent paralysis or weakness.
- So this is the main thing. So there's two big takeaways from this short little segement: one is that you have
- to make sure you have the information to make a diagnosis. For example, this over here you couldn't even
- do something useful because you're not able to see the number six and number seven. Exactly, we'd call
- it inadequate as you cannot draw any conclusions from that. That's why you would want them to get in
- that swimmer's position, raise the arm from the direction you're looking at from the direction you're
- looking at and lower the other arm. Correct. And then you can see something like this.
- This right over here is cause for trouble because now you can go all the way to seven, and you can actually see
- that they are not aligned. Absolutely, this is someone that you wouldn't let get out of your emergency
- department without seeing a spine specialist whereas if you didn't have that view, you might falsely be
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