How to Position a Perfect RAO Sternum

Back on May 15 for my 10th blog I shamelessly plugged my first textbook which I co-authored with Quinn Carroll titled “Adaptive Radiography with Trauma, Image Critique and Critical Thinking”.
I thought it would be fun every once in a while to write an article on one of my favorite parts from the book. This one today was a fantastic “Trick of the Trade” that I learned from one of my students about 5 or 6 years ago. It’s uncountable the amount of amazing things I’ve learned from my students over the years, since they’re working and learning from hundreds of different radiographers from 10 different hospitals and imaging departments and the techs in my own department!! So today I’m going to explain how to position a perfect RAO sternum every time.
This exam is almost always done upright. You begin by turning your patient AP and centering mid sternum so that you have 1 inch of light about the manubrium and 1 inch below the xiphoid (see figure 1).
 Fullscreen capture 12122013 13323 PMThen have you patient step to the side and get the Bucky/detector centered to your central ray. Collimate it side to side 4-5 inches and put the correct marker on the correct side. For speed sake, whatever lateral you’re going to do, use that marker so it will already be in play (see figure 2).
 Fullscreen capture 12122013 13329 PMNow bring the patient back over and place then in that gently 15-20 degree oblique (just steep enough to get the spine completely out of the way). Then make sure that their sternum is directly even with the horizontal line in the middle of the Bucky/detector (see figure 3).
 Fullscreen capture 12122013 13334 PMAt this point you are perfect and ready to make your exposure. I know it’s a very difficult thing to do, but don’t even turn your collimator light on to see where you are centered. This will just mess with your mind and not give you any information that you need. Your collimated light field will just be in the middle of nowhere on their back, but will look incorrect (see figure 4).
 Fullscreen capture 12122013 13342 PMThat’s because there isn’t a centering point for an RAO sternum. All the positioning books will tell you the correct centering is to exit mid sternum and you did at the beginning when you centered the patient while they were AP.
I’m going to end by saying that following those steps will give you a perfectly positioned RAO sternum every time. Unfortunately it doesn’t mean that you will end up with a textbook “looking” image though. After years of shooting and critiquing hundreds of sternums using film, CR and DR, I’ve come to the conclusion that it has everything to do with the anatomy of your patient. If your patient has the perfect density lungs, heart and sternum then you will have a perfectly visualized sternum. Fullscreen capture 12122013 13349 PMFigure 5 is the best RAO sternum I could find in our PACS system where I had hundreds to choose from. As you can see, it is pretty good, but not spectacular. So contrast wise, the next time you take one that doesn’t really look that great, don’t be too bummed but on the other hand if it looks like a textbook image, don’t take too much credit.

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4 Comments to “How to Position a Perfect RAO Sternum”

  1. Alan Himmel says:

    Good. In my experience, the hospitals are missing sternum fractures quite often. A good history is a good place to start. Ask about chest pain and tenderness upon palpation, movement or breathing. And, if the patient was in a car accident and slammed into the seat belt strap, the steering wheel or the airbag, you better know how to take an x-ray of the sternum and ribs. I have had several occasions where the patient was sent home with negative findings only to re-xray and find the fractures clear as day.

    • Hi Dr. Himmel,
      Thank you for your comments. Hopefully this article will help radiographers take a better oblique sternum. From my experience, most radiologist’s are really hoping they will see the fracture on the lateral since so often the lung markings obscure the detail of the sternum in the RAO. I believe when a breathing technique can be used one always gets the best detail. This article was only about positioning though, so I didn’t get into techniques or breathing.

  2. Sue W says:

    Thanks for those encouraging words because I just had to do a sternum today & my pts lung field was let’s say “very busy” my oblique were positioned ok but, as you said not very pretty. I work in a clinic setting so I’m able to communicate directly with the ordering provider. The provider did not really want to do this but the pt insisted, there was no trauma just some pain x 3 wks out. I felt I did the best images I could with the equipment I have to work with but now the Radiologist wants them repeated. My little tube can only do so much. Now repeating with additional exposure that will probably not produce any better images.

    • Hi Sue,
      Sometimes the other oblique can give you a better image. It’s weird that it works, but I’ve seen it happen. Also sometimes you can try a slightly steeper oblique. This doesn’t show the body of the sternum as well, but at least it’snow showing up.
      I’ve also tried moving the SID to 28-30″ (which might be good if your tube doesn’t have a lot of oomph. Lastly you can try a breathing technique, although their pretty hard for the patient to hold still enough.
      I’m glad you enjoyed the article. You might really like our textbook. Here’s the link to read more about it. It’s for sale at Amazon.
      All the Best,

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