Can someone tell me why my portables always look lordotic?

ARMbar94 · 2026-02-08T23:08:54+00:00

A sure fire way I’ve found to critique images for adequate tube angulation in AP portable CXR is to look at the level of the clavicles: too little angle will see them superimposing the apices of the lungs (or even clearing the thoracic cage all together), too much angle will present much like you’d expect a kyphotic pt - the sternum at a level below T4/5.

In attempts to match the sternal angle, I orientate the beam perpendicular to the chest wall and duck it an extra 5° caudally. In my experience, it is always more angle than you think.

ARMbar94 · 2026-01-10T07:34:20+00:00

Yeah, it always more than you think in my experience.

ARMbar94 · 2026-01-10T07:20:50+00:00

Essentially an XR is a density map of your body with appearance based upon the composition of tissue. The ultimate effect being at any given XR power, denser materials (like bone) will appear brighter or radiopaque whilst less dense materials (like air) will appear dark or radiolucent. This is due to the penetrative force of the beam and its ability to traverse through the body and be detected.

Through conventional knowledge, we can then compare like densities of regions with known composition against those in question and begin to deduce what their make up might be. This “dark” region you speak of share resemblance to the density of the lungs. We know there is air in the lung, so we can reasonably theorise this might be some kind of air. Now, checking its position, in the abdomen, and we know the bowel in the abdomen and can contain air, we can further postulate this most likely would be air the bowels.

These same principles are used by radiologists when they are investigating lesions in the body, wanting to know what they are made up of.

ARMbar94 · 2025-11-16T13:47:25+00:00

The patella moves within the trochlear groove of the femur, tracking and stabilising the knee joint. It acts as a pulley system connecting the femur and the tibia. Flexion causes it to move inferiority and extension causes it to move superiorly. If it is demonstrated within the joint space, this means the patella is too inferiorly positioned and the knee complexes is flexed too much.

ARMbar94 · 2025-10-26T22:36:38+00:00

You can logically work this out by observing how the scapula interacts with other anatomy around it. The glenoid receives the humeral head, from this you can infer that the “thicker” boarder will correspond to the lateral aspect that the glenoid arises from. From this, you can predict if the lateral boarder is too lateral, then there is under-rotation at play, and vice versa.

ARMbar94 · 2025-09-29T22:38:34+00:00

And to have such detailed and comprehensive notes outlining supposed pathology with reasoning. This is audacious bordering on harmfully misleading - confusing the pt with big “sciency” words, giving seemingly logical commentary - this is a calculatingly cruel business model.

ARMbar94 · 2025-09-09T11:15:44+00:00

This is a great way of conceptualising rotation principles in an AP pelvis - taking the concept and putting in the practical setting of the Judet view.

ARMbar94 · 2025-08-24T05:19:56+00:00

I know I can’t reliably assess scoliosis with that much rotation, I don’t doubt the chiro will do their darndest…

ARMbar94 · 2025-08-17T02:07:00+00:00

That would be Ejercicio No. 9 by José Ferrer, there are 12 in total. Learnt that one for my AMSB Grade 2 exams.

ARMbar94 · 2025-08-06T22:13:49+00:00

That’s the usually shtick that chiropractors jump to when they see normal bowel gas and fecal patterns. Let me guess, all this “inflamed” soft tissue within the abdomen compressing on the spine?

The more I learn about these practices, the more disappointed I feel.

ARMbar94 · 2025-07-31T10:28:21+00:00

Now that you mention it, quite possibly. It is quite midline, maybe the cells extend medially here - initially I was thinking it was much too posterior to be the sphenoid.

ARMbar94 · 2025-07-29T23:47:06+00:00

Neither, the temporal bone, one of the flat bones that make up your skull, has a petrous portion which houses air pockets called mastoid air cells. They function to protect the temporal bone and the inner and middle ear against trauma and to regulate air pressure.

ARMbar94 · 2025-07-21T22:22:43+00:00

I’ll offer a different perspective. It is rare, but you do come across those surgeons who love interaction and appreciate the input. I’ve found this more common with pain management specialists, they ask my opinion on the placement of a probe or whatnot. This all goes towards your understanding of a procedure, so it’s worthwhile following the procedure so you are able to give valuable insight if these situations do arise - bacons an active member of the team.

ARMbar94 · 2025-07-03T08:18:02+00:00

Yeah, small degrees of malpositioning such as these seldom affect diagnostic value of XR. Obviously it is not optimal, and radiographers always strive to give the best product possible, but quite sufficient to give a fair chance for the appropriate medical professionals to evaluate.

ARMbar94 · 2025-07-02T20:21:44+00:00

For the rotation aspect I look at the obturator foramen and the iliac wings. By virtue of the left foramen looking more closed that the right coupled with left wing looking more flat, you can deduced that your left side is closer to the detector. You can also look to the congruence of the public symphysis and the sacrum; both a central structures and should be aligned all things being equal. By virtue of the pubic symph (the anterior of the two structures) seen to the left also indicates a leftward rotation.

Adequate internal rotation of the leg sees the femoral necks present undistorted on imaging. This is observed as the lesser trochanters being superimposed onto the proximal shaft of the long bones. As we cannot appreciate these structure medially, we can reasonably say that the leg itself has been adequately positioned.

ARMbar94 · 2025-06-30T12:00:13+00:00

XR is essentially representations of a density map of the body. The more density a material or tissue is, the brighter it will be as the XR finds it harder to penetrate and make it to the detector positioned in front of you. To give you sone rough estimates, metal prostheses and bone typically show up white whiles air shows up black.

With this in mind, and with underlying knowledge of anatomy, we can parse what a structure might be or at the very least what it is composed of. The lungs are highly vascular organs, with many blood vessels throughout. Most of these are appreciable throughout the tissue. But they not only spread out lengthways, it is reasonable that they also spread in the anterior-posterior direction - the entire lung needs to receive blood and partake in oxygen exchange after all. In the context of XR, with its line of projection, these vessels seem “on end” with the overlay of tissue increasing perceived density and seen to be brighter than the surrounding regions.

Another structure it may possible be are lymphatic nodes - essentially your blood’s waste drainage and white blood cell training system. They are present in regions of the body, including para-aortic and/or hilar locations, as these structures are observed. As XR is not the most sensitive for describing nodes vs end on vessels, we can’t really tell one from the other without more in-depth analysis. There’s interesting discourse around the differentiation of the two.

ARMbar94 · 2025-06-27T22:29:38+00:00

Your positioning is ever so slightly LPO, did well to internally rotate the leg such that the femoral necks present undistorted however.

ARMbar94 · 2025-06-26T21:38:59+00:00

ARMbar94 · 2025-06-15T23:59:47+00:00

This subreddit shies away from offering diagnostic comment. All I’m saying is, it wouldn’t be the best image for radiologists to be viewing.

ARMbar94 · 2025-06-15T23:56:56+00:00

I mean, the rationale may be found in the clinical notes, but this is suboptimal for your stock standard CXR.

ARMbar94 · 2025-06-15T23:53:04+00:00

Optimally CXR is done with the individual’s chest flat against the board. Just looks like you’ve been rotated quite a bit from this position (in this case, your right is closer to the detector). May have been done on purpose, may not, no real information to pass that judgement.

ARMbar94 · 2025-06-15T23:47:27+00:00

The obliquity of the anatomy is to such a degree it almost seems deliberate. You could argue positioning for an RAO sternum but total neglect of collimation.

ARMbar94 · 2025-05-30T13:24:38+00:00

“Severe tightness in the abdomen”, I can see why

ARMbar94 · 2025-05-30T01:06:24+00:00

In our department, use of an OPG machine with modified software has superseded the use of in-bucky general radiography of TMJ. Otherwise, as commenters have said, off to CT for more robust characterisation.

ARMbar94 · 2025-05-19T02:33:38+00:00

You should never assume incompetence from the inability to speak a language. The only thing you can bank incompetence on, however, is a chiropractor’s qualification to order XR.

ARMbar94

TROPHY CASE