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rtremb
09-05-2007, 03:44 PM
I am wondering if anyone has had any problem finding out the actual Cobb angle of their curves?

We have a huge discrepancy between the doctor's measurements and the official radiology report from the Children's Hospital of Eastern Ontario (CHEO).

The doctor told us, at an appointment, that my daughter's angles were T56 and L50. One week later he changed his reading to T52 and L49. The doctor recommended surgery in six months.

The chiropractor measured the angles in front of us and got T45, L45.

Today we now have the official radiology report from CHEO which states her angles are T42 and L38.

The difference between these readings is huge. Our paediatrician has told us in the past to trust the radiology report (there has always been differences before between the doctor's reading and radiology).

Has anyone else come across these discrepancies in the reading of Cobb Angles?

scoliboymom
09-05-2007, 09:21 PM
I actually learned how to measure the cobb angle and always got a copy of the x-rays, more because I couldn't wait to find out what was happening with my sons spine. My results were within 5 degrees of what the doctors found. One time the radiologist made a mistake and found the curve hadn't changed at all when in fact it had increased significantly. I e-mailed the doctor and asked if he could remeasure and he did and he agreed there had been a mistake.
I wouldn't hestitate to ask the surgeon to remeasure the x-rays. The results you are getting are quite different and do make the difference between possibly needing surgery or not.
Is it possible to get another doctors opinion?
My son had his surgery this year at Sick Kids in Toronto and for the most part it was a positive experience. Their ortho team is nothing but excellent. Maybe you could get a second opinion from them?
By the way has your daughter finished growing and have her curves been steadily increasing?

Ramona

rtremb
09-05-2007, 11:03 PM
Ramona:

Thanks for your post.

These new Cobb angles from radiology are their second read on Esme's x-rays (the surgeon asked for a second read from them since the first read seemed so off). The surgeon has also done two readings as well!! We are a bit confused to say the least but we will keep trying to get to the bottom of it. We were very devastated when the doctor said Esme needed surgery so we are hopeful the radiology department has the right readings (wishful thinking!!). I will ask for a copy of Esme's x-rays from now on.....

We are going to see Dr. Rivard in Montreal as soon as we can get an appointment - he has agreed to see our daughter Esme. Hopefully they will give us a less confusing read on her angles. We are hoping for a Spinecor brace.

Our daughter's scoliosis is s-shaped and has been progressing steadily over the past 2+ years. She is not finished growing. The surgeon estimated she is a 0-1 Risser although he couldn't be sure since they didn't have the appropriate x-ray to show that clearly. She is premenarchial.

Our son has an s-shaped scoliosis too and it looked like he was headed for surgery however we were fortunate - his curves seem to have stopped progressing and have even reduced a bit. He did not wear a brace. He is 17 this weekend so we are hoping his curves won't progress now.

Glad to hear all went well with your son's surgery. It must be so hard to go through - I think it must really help if you have doctors you feel good about.

rtremb
09-28-2007, 11:10 PM
At this point we are having to think the radiologist made an error when he read Esme's x-rays since three doctors have now measured her curves at or just over 50 degrees. The radiologist who read the x-rays is away until later in the month so we aren't able to get an explanation from him yet.

rtremb
03-17-2008, 02:05 PM
Does anyone know an internet link that describes how to measure thoracolumbar curves?

Susie*Bee
03-17-2008, 02:46 PM
This site might help you out... scroll down a little and it shows how to figure Cobb angles.

http://www.pediatriceducation.org/2006/12/11

The main problem with different people determining the angle is that they might choose different beginning and ending vertebrae, which would throw the whole thing off. Sometimes looking at the x-ray, it doesn't look like a definite "this is where to start" spot... and even just drawing the lines can lead to some error, so that is why they say give or take 5º.

You can probably pull up other links just by googling "how to measure cobb angles"--

WNCmom
03-18-2008, 08:01 AM
This site might help you out... scroll down a little and it shows how to figure Cobb angles.

http://www.pediatriceducation.org/2006/12/11

The main problem with different people determining the angle is that they might choose different beginning and ending vertebrae, which would throw the whole thing off. Sometimes looking at the x-ray, it doesn't look like a definite "this is where to start" spot... and even just drawing the lines can lead to some error, so that is why they say give or take 5º.

You can probably pull up other links just by googling "how to measure cobb angles"--


Ruth--

This is what happened to us. Our chiro actually got a bigger angle than the hospital did, and he told us he was measuring a different vertebra that had the greater angle. Since then we've been going with his measurements so we can compare apples to apples.

txmarinemom
03-18-2008, 01:04 PM
And, actually, if the x-rays are read by different doctors, the margin of error can be ±10°.

Regards,
Pam

Singer
03-18-2008, 02:06 PM
I had a radiologist and 2 different scoliosis specialists read my x-rays and their measurements were 55, 60, and 70 degrees, respectively. I noticed that my surgeon measured my main curve on the outside of the curvature, whereas the other specialists measured it on the inside.

txmarinemom
03-18-2008, 02:52 PM
I had a radiologist and 2 different scoliosis specialists read my x-rays and their measurements were 55, 60, and 70 degrees, respectively. I noticed that my surgeon measured my main curve on the outside of the curvature, whereas the other specialists measured it on the inside.

Singer, by "on the outside", I assume you mean from the top (or bottom) of the vertebra? (mine was T5-L1 ... it was measured above T5, and below L1).

That's actually the only way I've ever had anyone measure mine (in almost 30 years), and everything I've ever read on Cobb measurement describes it that way. Measuring below the top involved vertebra or above the bottom involved vertebra (preaching to the choir here, I know!) could make a HUGE difference.

It could also be VERY dangerous - and an invitation for decompensation. Eek!

Even the surgical plan with one doctor can vary. Hanson and I had agreed on T5-L1, but the morning of surgery (after more examination of the films) he said he'd really feel better if we took T4 as well because he felt it *could* possibly be involved in the structural curve.

T4 for me was kind of a no-brainer since I'd already agreed to T5 (and it's not really a "bending area", per se).

I honestly feel he did the right thing going higher: The cervical pain I had in the compensatory curve (whiplashed area also ... 3mm protrusions at C5-C6/C6-C7) is GONE. Maybe it has nothing to do with fusing higher, maybe so.

Now, if he'd told me he wanted L2, I've had probably put things on hold.

I know plenty of people get on with life with a lumbar fusion (and remember my curve wasn't progressing, nor did the MRI show degeneration), but I think I'd probably have decided to tough it out a few more years (yes, for softball).

At some point I'd have let him do it if he thought it was necessary, I just wasn't ready YET for that. Luckily, I didn't have to make that choice.

Regards,
Pam

rtremb
03-18-2008, 02:55 PM
Thank you all for your comments. We have had this happen in the past too where the x-ray readings differ radically when done by a surgeon, a chiro or the radiology department.

While I can see that Esme's curves have progressed I wanted to check the measurements myself but am not quite sure how to figure out which vertebrae is which so I can compare the measurement to previous ones (i.e., use the same vertebrae to measure).

Also since Esme's has two curves (thoracolumbar) not sure where the apex would be.

Ruth

txmarinemom
03-18-2008, 03:01 PM
Each structural curve should have it's own apex, Ruth.

Regards,
Pam

rtremb
03-19-2008, 12:37 AM
I have attached Esme's March 13, 2008 x-ray. Scary looking!! If anyone would like to measure it and tell me what you think her curve measurements are I'd really appreciate it.
Ruth

txmarinemom
03-19-2008, 01:36 AM
I have attached Esme's March 13, 2008 x-ray. Scary looking!! If anyone would like to measure it and tell me what you think her curve measurements are I'd really appreciate it.
Ruth

Ruth, I realize you're looking for answers, but unless we have a surgeon on this board, I REALLY think it's a bad plan to have a bunch of laypeople (and I don't care *how* many times they've played around with their *own* x-rays) measure Esme's.

You've seen written where even with professionals the margin of error can range from ±5° to ±10°. You need to wait and get YOUR surgeon's answer.

What you're asking is definitely setting yourself up for more confusion - and potential freak out ... just because someone knows how to do it *IN THEORY* doesn't mean they can do it accurately.

Regards,
Pam

Aussiemum
03-19-2008, 04:35 AM
In all honesty Ruth - what does it matter??

If she had one doctor telling you 30 and another one 42 THEN I could understand the urgency in deciding the correct measurement. As you know the consensus is once over 40 degrees bracing is no longer contemplated.

So while I understand you wanting to know the EXACT measurement (as I would) I don't think it really comes into play in making a decision for the next step. Her x-ray looks quite severe to me.

It seems everyone has their own style of measuring the cobb angle (I experienced something similar to yourself between doctors) but so long as you get the same person each time to measure the progression then the rate should be accurate. I just stuck with my Surgeon and his expertise, I never relied on what the Radiologist wrote. I just figured my Scoli surgeon was looking and measuring these types of things all the time and he was the most qualified to do the job.

It's all very frustrating, isn't it! Hope you can get it all sorted out one way or another.

Cheers
Del

rtremb
03-19-2008, 03:33 PM
A concern I have with getting an accurate read of the x-ray is that if Dr. Rivard's mesasurement is correct Esme's curves are advancing at an alarming rate. 14 degrees in just over three months seems fast to me anyway. If she is advancing that quickly then she needs to see the doctor at CHEO sooner than the April 28th appointment they have given us.

I don't mind if people want to have a try measuring her curves. I have been doing it with the software which came with the x-ray files and have been unable to come up with the same cobb angles as Dr. Rivard - my measurements are coming out lower but still in the 50's. When I measure a hard copy with a ruler and a protractor I am getting lower measurements too.

I am not going to base any decisions for action based on the measurements anyone comes up with - I am just curious what other people might get if they try to measure her curves.

Ruth

DaveWolpert
03-20-2008, 02:39 PM
I wanted to add my two cents on a few things here:

First, in general, I would not rely on a chiropractor to measure a scoliotic curve. They rarely have any formal training on how to do this, and I’ve seen some horribly inaccurate measurements from some. So, Ruth, of the three measurements you received, I’d only consider the surgeon’s and the radiologist’s as meaningful.

Second, as others have noted, keep in mind that there’s a margin of error of 5-10 degrees in Cobb angle measurements, not just due to choices or errors in measurements but also because a spine’s curvature may vary by a few degrees over the course of a day. I'd focus on the largest curve measurement (thoracic), not the smaller one (lumbar).

Third, I agree with Aussiemum’s general point that knowing the exact measurement isn’t critical. Whether Esme's thoracic curve is 42 or 56 degrees, it’s clearly close to or in the lower-end of the range at which surgery is indicated (most surgeons have a 45 or 50 degree minimum). And, because Esme is only 13 and surely has some more growing to do, it’s statistically almost a certainty that her curve will progress further – how much so is impossible to predict, but even if it progresses 10 more degrees by the time she’s skeletally mature, surgery will almost certainly be recommended by your surgeon eventually.

Also, the rate of curve progression isn’t linear. Even if Esme’s curves have in fact progressed 14 degrees in three months, that doesn’t mean they’ll progress by the same amount in the next three months.

I hope this helps!

Dave

txmarinemom
03-20-2008, 02:52 PM
Nice to officially "meet" you, Dave!

BTW, *fantastic* book. My surgeon recommends ALL his patients read it before deciding on surgery, and in turn, I recommend it highly every chance I get.

Best regards,
Pam

rtremb
03-20-2008, 04:06 PM
Thanks Dave.

I agree with all you say. I am still finding the idea of surgery hard to handle though and we were pursuing non-surgical treatments for Esme which we have to decide whether to continue with or not or whether to go straight to surgery.

We only have one doctor's reading of Esme's x-rays so far.

The measurement matters to me in that the structural integration treatments Esme has been having (10 so far) have made her back look cosmetically really really great but the x-rays are showing a different story. In fact it seems to me that the cobb angles don't fit with the photo of her back.

I have attached a photo of her back which you can look at - I want to leave it on here only for a couple of days.

Ruth

Aussiemum
03-20-2008, 04:23 PM
Hi Ruth,

I can see where your coming from because Esme's back does cosmetically look quite okay. Elysia didn't have the Lumbar curve that Esme had and she had much more of a tilt on her than Esme has. I think I'm correct in saying that for Esme the reason is that she has an S curve - Thoracic 62 and Lumbar 63 - wasn't that one of the measurements they gave you? So that means that her trunk is bending one way and then again the other.

After she has surgery you will definately see some major height changes for her. Scoli x-rays look very scary - you can't always see the real internal drama that's going on from the outside. Have a read of our blog, Elysia's before and after x-rays are on there. I'll try and put up a picture later of her back before surgery on there as well - there's one of her hump if you scroll down through the older posts.

cheers
Del

Aussiemum
03-20-2008, 04:32 PM
There you go Ruth - I've put up the before and after shot on the blog - wow - even I'm impressed looking at the difference between the two. Elysia is quite thin too so not much there to hide anything - I could see her curve in her spine just with the naked eye! But she's all skin and bones.
So, if she had a large Lumbar curve she would have balanced out as well.
Hope this helps somewhat.
Del

rtremb
03-21-2008, 02:30 PM
Del:
Thanks for sharing the photos. Elysia's back looks really good now.
Ruth

S4Sarah
05-28-2009, 10:05 PM
That happened to me, the Radiologist, the reviewing doctor, and my actual doctor had different results. They were like 5 degrees off. it does not sound like too much but it can make a difference in treatment. that five degrees made the difference between mild and moderate. My Lumbar curve is now moderate and Mid-Throatic curve is mild. I think they are a little off though, they feel worse than what my real doctor who corrected them said. They also feel worse at the end of the day I have heard about curves worsening a couple degrees throughout the day then going back. It has to do with the flexibility of the spine or something like that.

Anyway I have my X-rays on a CD and would like to measure them myself. Any good websites or tips? I tried doing it on the computer but I don't think I did it right because every time it came out to really outragous numbers like 40 degrees.

txmarinemom
06-04-2009, 01:42 AM
That happened to me, the Radiologist, the reviewing doctor, and my actual doctor had different results. They were like 5 degrees off. it does not sound like too much but it can make a difference in treatment. that five degrees made the difference between mild and moderate. My Lumbar curve is now moderate and Mid-Throatic curve is mild. I think they are a little off though, they feel worse than what my real doctor who corrected them said. They also feel worse at the end of the day I have heard about curves worsening a couple degrees throughout the day then going back. It has to do with the flexibility of the spine or something like that.

Anyway I have my X-rays on a CD and would like to measure them myself. Any good websites or tips? I tried doing it on the computer but I don't think I did it right because every time it came out to really outragous numbers like 40 degrees.


You know the margin of error is ±5°, right? It can be as much as ±10° if shot by a different x-ray tech and read by a different doctor - especially when switching between scoli specialists, MD's, DO's and DC's ...

And, hon .. ±40° isn't all that "outrageous". Especially if you measured them yourself.

FixScoliosis
06-04-2009, 08:44 AM
Hi S4Sarah

Measuring the Cobb Angle is quite easy.
Here is a good description on how to do it.
http://www.e-radiography.net/radpath/c/cobbs-angle.htm

good luck.

titaniumed
06-04-2009, 12:53 PM
Due to the parameters involved in measuring cobb angles, one of the things that was nice with me was the fact that I had 25 years of x-rays. I can actually wallpaper my bedroom with all of them.

You can see the fluctuation of angles through the years, with minimal movement from age 25 to 40. In other words, I could average all the angles out, and come up with a number. You can also see where I had ski crashes and vertebrae would move out of position and eventually return to their mean scoliotic position.

My problems started at age 41. That's where I started progressing.

I've been exposed to a few REMs through the years...... No cancer so far, knock on wood. Must be all the veggies and the hydrogen peroxide. LOL
Ed

concerned dad
06-04-2009, 03:19 PM
There is a new method I saw proposed by some doctors in Asia. Their paper discussed all the problems and challenges with measuring the Cobb angle. Their method, they claim, significantly reduces the errors.

Attached is a Figure from their report comparing their method with the Cobb method. I may give it a try and compare my daughters pre brace and inbrace x-rays from Montreal.

I do see one problem with their method and am wondering if anyone else picks it up.

And, S4Sarah, I am guessing you have more than one curve (S?). I could be wrong but I think multiple curves probably add some challenges to the reading, at least so far as picking the right vertebrae to use for the end points. My daughters curve is much like the one inthe attached figure and is pretty simple to pick the right end points (although, <cough> apparently some people in Montreal may disagree)

SpiderPug
06-04-2009, 04:47 PM
Concerned Dad,

I see this problem with the new method: The method appears to assume that the C7 vertebrae is centered over the pubic symphasis. However, this is not the case in many with scoliosis, so the upright line would be tilted at an angle, especially in those with a trunk shift. This would seem to make the measurements inaccurate.

Is this the problem you see, or did you see something else?

FixScoliosis
06-04-2009, 05:25 PM
Good that you picked it up CS.
SpiderPug, you are correct it that there should be mentioned how much C7 is off the vertical alignment with reference to pubic symphisis.

I wrote a blog post about that paper a while back 'Cobb Angle compared with ALDT to measure Scoliosis (http://www.fixscoliosis.com/2009/05/09/cobb-angle-compared-with-aldt-to-measure-scoliosis/)' and I would suggest to combine both methods.

just my 2 cents..

concerned dad
06-04-2009, 08:16 PM
Concerned Dad,

I see this problem with the new method: The method appears to assume that the C7 vertebrae is centered over the pubic symphasis. However, this is not the case in many with scoliosis, so the upright line would be tilted at an angle, especially in those with a trunk shift. This would seem to make the measurements inaccurate.

Is this the problem you see, or did you see something else?

No, that's not what I picked up but a point well taken.

I was thinking along the lines of the fact you are measuring a distance rather than an angle.

The distance between the film and the subject doesnt matter if you are measuring an angle. It does matter (I think) if you are measuring a distance.

titaniumed
06-04-2009, 11:03 PM
My 4cents. I added 2 for inflation....

When having problems in measurements, adding another dimension from somewhere else aids in inspection. It is used and is in relation to the other measurements. I say use both systems. Dr Cobb devised a simple method as some measurement criteria needed to be devised years ago.

Focal points in optics can present problems in accurate measurement. Problems arise viewing across flat surfaces and 3 dimensional shapes. Objects can appear larger or smaller dependent on focal distance.

Measurement under a few degrees is and will continue to be difficult unless there can be a physical method of measurement that's accurate and then averaging over a period of time to account for daily movement.

ALDT does not show the severity of the cobb angle, however it is an easy way to gain another dimension which is useful.

This will help explain.

Pooka1
06-05-2009, 05:51 AM
In re Cobb angles, the issue is trying to detect a change. It really doesn't matter if the angle measurement is accurate in some absolute sense but it has to be as precise as possible so that when a change is measured, there can be some confidence it changed that amount.

It's like certain uncalibrated analytical instruments... it may not be accurate (the real concentration is x when the instrument says y) but x and y are always the same difference.

Cobb angles are always going to have a huge error term in them from just how the person stands for a particular radiograph. Unless you have amazing body control, two readings 5 minutes apart are likely to differ measurably. Recall that the Spinecor folks produced a change of 11* just by posing the patient.

Here's what I mean by body control...

body control (http://farm4.static.flickr.com/3188/2799764426_c9d7455214.jpg)

:D

Pooka1
06-05-2009, 05:53 AM
The distance between the film and the subject doesnt matter if you are measuring an angle. It does matter (I think) if you are measuring a distance.

Yes you are right. There is a move afoot by some horse lameness specialists to standardize the radiographic protocol when imaging hooves in terms of all kinds of parameters. It's very important.

concerned dad
06-05-2009, 08:21 AM
Ed, That is an interesting point you bring up with your sketch. I know you emphasized the difference to get your point across, but don’t you think if both spines were straight they would have different heights. I mean, wouldn’t the effect be less for a curve change on a given spine?

The Chinese authors note that they obtained a positive correlation between the measurement method and the Cobb method. Particularly for single curves and balanced curves (not exactly sure what they mean by “balanced” but perhaps that goes to the point that SpiderPug identified.

Regarding the relationship between Cobb and ALDT they say:

Finally, the ADLT (sic) measurement has positive significant correlation with the Cobb measurement (r = 0.73, P = 0.05), indicating that the ALDT is valuable. At the same time, the change in spine balance and curve types will affect the correlation coefficient which we should pay attention to. In this study, the correlation coefficient for imbalance group is smaller than that of balance group, as well as that of the 2 curves group smaller than the single curve group.

FixScoliosis does a good job at presenting the information from this paper on his blog. A read some of the other posts there and I am guessing FS often needs to bite his tongue reading posts here - subscribing more to the SOSORT philosophy than the SRS way of thinking.

Finally, I know Sharon pounds away at the peer review quality of scoliosis papers. It is interesting that the apparent typo in the quote above escaped the review process (ADLT vs ALDT). This paper is in the Journal Spine.

titaniumed
06-05-2009, 02:32 PM
Sharon is correct. Detecting change is what you are looking for.

Inspection instruments should be traceable to NIST.
http://www.nist.gov/index.html

If they are not traceable, then they Are to be labeled "for reference only" This is the easy way out. If in doubt as to accuracy of a measuring instrument, like measuring spines with an x-ray, then it should be considered as a supplement.

When the astronomers were viewing the solar eclipse back in 1919 to try to prove Einstein's theory that space is curved, the hundreds that took these measurements were hesitant to release their findings due to the compound inaccuracies of measurement with optics. They had multiple findings that were all different, and debated their methods. Sound familiar? Well its the same thing with measuring spines. Too many parameters.......

Sharon, love that elephant! Boredom can produce bizarre thought sometimes.LOL Someone must have been bored to think of producing something like that. Teaching children to think when they are bored, is a good thing. I wonder if that elephant had scoliosis, would he be able to balance as well as he is?...

CD, height is another easy measurement to use. In fact, its the easiest. Anyone at anytime can record height change very easily. In fact its a great way to teach about measurement, and height changes to children with scoliosis. One measurement at 8AM,3PM, and 10PM to explain and prove that the spine settles due to various effects.

That 150 degree example was no exaggeration. There was an example I saw on The research channel of a young male who had a about a 180 degree u-turn, in about 7 or 8 vert in the thoracic that the Docs corrected. I will look for it for you. This will prove that "positive correlation" ratio cannot always work in every case.

Measurement of spines doesn't really need to be all that accurate. Like Dave Wolpert says, within 5-10 degrees is sufficient. 40-50 degrees and age are determining factors for surgery. Its the movement that is worrisome, due to the fact that it can happen so fast. If there was a guarantee that every scoliotic would only progress 1/2 degree per year for an 80 degree lifetime, the result would be a total curve of 40 degrees and no-one would have to worry about anything except maybe a little pain. People adapt to pain.

Scoliosis is serious and then its not. You can look at it both ways. I try not to think of it as being so serious, there are times where I try not to think about it so much as it does have a tendency to wear one down with worry. This is where the "knowledge is power" thing should be used in a kind of a balance, to keep ones sanity. "Knowledge is power" is a good thing for most, but maybe not to a child with a terminal disease.

Ed

concerned dad
06-05-2009, 03:22 PM
I agree, especially about the issue of detecting a change rather than an absolute number.

But I have run into an issue with the inaccuracies of the Cobb measurement. I disagree with one of my daughters (former) doctors about the measurements of her inbrace Cobb. His response is both; 1. it is not uncommon to have different measurements from different people and 2. he picked different vertebrae than myself. (well, there is 3 too: he has a lot more experience than myself)

Using this new ALDT method may reduce the error in (1) above and negate the error in (2) above.

What I don’t understand about the xray process is the effect of the distance between the source of the xrays, the subject, and the film.

Is it like a flashlight, where the beam broadens as the distance increases, ie, one single point source of xrays?
Or,
Is it a uniform source of xrays such that distance measurements are valid?

Pooka1
06-05-2009, 07:13 PM
Sharon, love that elephant! Boredom can produce bizarre thought sometimes.LOL Someone must have been bored to think of producing something like that. Teaching children to think when they are bored, is a good thing. I wonder if that elephant had scoliosis, would he be able to balance as well as he is?...

Maybe he could learn to compensate.

Here's the picture I was looking for when I found the elephant...

headstand #1 (http://yoga108.org/images/blog/2007/585.jpg)

That guy do learn dressage quickly in my opinion.

So could this guy...

headstand #2 (http://komarix.org/per/yoga/jeero_yoga_photos/medium/jeero_headstand.jpg)

titaniumed
06-06-2009, 12:49 AM
CD

No matter who does the measuring, or how they do it, there is nothing like comparing multiple x-rays to check for movement.That's why I have always said that everyone should get their own dated copies of their x-rays in their possession. There is no reason why they shouldn't give burned copies on disk to each patient. That way the patient can view these next to each other on their home computers.

Physics class! ... fun fun fun.
here are a few articles to read
http://en.wikipedia.org/wiki/Focal_length
http://en.wikipedia.org/wiki/Focal_plane#Focal_points_and_planes
http://en.wikipedia.org/wiki/Fluoroscopy

Now, it is possible to do this. Maybe not practical,maybe dangerous, but

I'm not a radiologist, and I am not aware of current technologies which are changing every MINUTE of the day, but I think that if a person were to stand in front of a fluoroscope, a machine that could "automatically focus" along the spine, have that person bend to the left,shoot the length of the spine,stand straight,shoot,and to the right, and shoot, then have a computer analyze the data, then we might have something worthwhile. To have actual video of the movement of the whole spine through left to right bending would produce fantastic results which could be stopped frame by frame for analysis. This is just 2 dimensional. 3D would be even better.

The auto focus would be needed for lordosis and kyphotic curves or corkscrew shapes. The focal areas that are shot for this video would have to be loaded into a 3 dimensional x-ray and or cad program.

I say dangerous to to the amount of REM exposure. ??? I don't know. Surgeons use fluoroscopy to place screws,
http://journals.lww.com/spinejournal/Abstract/2006/10010/Radiation_Exposure_During_Pedicle_Screw_Placement. 19.aspx
Oh boy, I think I will thank my surgeon, one more time.

Just like shooting a video of a car spring with a 6 inch diameter, if the focal point is 6 inches, and the camera followed the helix up that spring, it would have to stay 6 inches away at all times to stay in focus.

Of course all x-rays or spinal video should be shot immediately after 8 hours of sleep with a maximum timeframe.

I'm sure the various companies that make this equipment have thought about this.
Ed

concerned dad
06-06-2009, 06:31 AM
is nothing like comparing multiple x-rays to check for movement
I agree 100%. The troubling part of my disagreement with the doctor about my daughters xrays was not so much the different reading we obtained, but the similarity between her pre-brace and braced xrays. (our measurements agreed on the pre-brace xrays).
Except for the brace rivets, they looked identical (even when overlayed using a graphics program - I am thinking about creating a blink animation)

The Links you posted didnt answer my question about xrays or at least I wasnt able to figure it out.

The film is recording the "shadow" from the interaction of the xray source and the bones.

If the source of the xrays comes from a point source, then the shadow SIZE will change as the distance between both the source and bones and film varies.

If the xrays are coming from a planar source, the rays will be perpendicular to the bones and the film and the shadow SIZE will not change based on positioning.

This link (http://en.wikipedia.org/wiki/File:Cardinal-points-1.svg) you provided shows the focusing of rays by a lens. (the top image is how I imagine we would want the xrays to behave - ray paths perpendicular to the subject)

But I didnt read anything about a lens in the xray link.

I'm not sure if I'm explaining my question right. It is sort of analogous to casting a shadow on a wall using a single light bulb vs a 8 ft fluorescent tube bulb.

S4Sarah
06-17-2009, 04:33 PM
So I used the software my x-ray CD had and I drew lines where the curve started/stopped, then I used another tool and made an angle so each side touched the outer part of the spine. I'm not sure if I did it right but I got measurments close to what the report said so I think I may have done it right.
Here is a photo of my bottom curve 22 degrees, did I do it right? Do any of you think it's worth a Spinecor? I also have a top curve of 11 degrees, and my skeleton is tilted.

concerned dad
06-17-2009, 05:33 PM
Sarah, I applaud you for taking an interest in the xrays and trying to figure things out yourself. You really need to be cautious taking anyone’s advice. You need to listen to your doctors and your parents.
Having said that, I have a comment and a question.
The quality of the xray seemed pretty poor. I had a tough time seeing the lines of the vertebrae. Where your xrays taken on two films or did they do a full spine xray?
Contrast the quality of your xray with the attached which seems (at least to me) easier to read. I think I would have a hard time convincing myself I measured things correctly on an xray like the one you posted.
Also, I saw you say on another post that you are in 10th grade and have a 22 and 11 degree curve. I presume those measurements are out of brace. Can you share your prebrace curve history?

Note: the attached xray was extracted from a full spine xray.

concerned dad
06-17-2009, 05:48 PM
What the heck, I might as well throw this one up there too.
Anyone see a way that this could be measured as 26 degrees?

:mad:

Pooka1
06-17-2009, 05:57 PM
What the heck, I might as well throw this one up there too.
Anyone see a way that this could be measured as 26 degrees?

:mad:

No. I am looking at my daughter's 27* radiograph and it is noticeably different. If that is 26* then my daughter's is not 27*... one or the other.

That's outrageous in my opinion. You were paying for expertise that you clearly weren't getting.

S4Sarah
06-17-2009, 09:12 PM
I know, I wanted to know if I did it right. I used the software that came on the CD Apicas or something like that. The original x-ray was full, the quality was not so good then I took a pic of my computer screen since I could not save the image to my laptop using the software
I was never in a brace but was given the option when I was 12 and my parents and I said no. I progressed after that quite a bit.
My last doctor was not what I would call a fantastic doctor. I have asked my parents about Spinecor, my Dad likes the idea of chiropractics, but my Mom doesn't. I sent my Mom a Email about Spinecor and told her about it and she was just sort of like "Mhhhhh Hmmmmmmm" IDK what to do (Sigh)

The picture you attached looked a lot bigger than 26 degrees.

LindaRacine
06-17-2009, 09:54 PM
Hi...

I have a book published by Medtronic, that is the official guide to measuring curves, for the Spinal Deformity Study Group (a large, multicenter study database). There are all sorts of modifiers, many of which require measuring the lateral films as well, so I'm not sure that any of us can accurately measure Cobb angles without first being trained to do so.

Regards,
Linda

concerned dad
06-18-2009, 08:06 AM
[COLOR="Purple"] ....then I took a pic of my computer screen since I could not save the image to my laptop using the software

a useful trick I learned is to use the "printscreen" key. This copies whatever image is on your computer screen to your "clipboard". You can then open any picture editing software (like microsoft photo editor which comes w/most computers) and paste it as a new image. You can also crop out other private information.


I have asked my parents about Spinecor, my Dad likes the idea of chiropractics, but my Mom doesn't.

There is a lot of mixed opinions on the Spinecor. My daughter liked the idea of a soft brace but she found it very uncomfortable. But, she never wore a Boston brace so she really is not in a position to compare.



The picture you attached looked a lot bigger than 26 degrees.

You have a better eye than one of my daughters former doctors.

Ballet Mom
06-26-2009, 04:15 PM
I'm sorry CD, that's just not right that that happened to you. I think you're right, the spine field really is a minefield.

concerned dad
06-29-2009, 11:11 AM
Thanks Ballet Mom. yeah, it is disturbing. I'm glad I discovered it before I had her wear the brace for long. I would have been furious had I discoved it after she wore the brace for 6 months. Probably furious enough to take legal action. Now I am just ticked and happy I discovered it when I did. (And I probably wouldnt have even looked if not for the folks here who got me thinking about it)

I encourage EVERYONE trying the SpineCor to get their kids inbrace xrays confirmed by an independent qualified doctor. Maybe I am the only one with what I perceive to be a significant discrepancy. I truly hope that is the case.

txmarinemom
06-30-2009, 11:53 PM
Thanks Ballet Mom. yeah, it is disturbing. I'm glad I discovered it before I had her wear the brace for long. I would have been furious had I discoved it after she wore the brace for 6 months. Probably furious enough to take legal action. Now I am just ticked and happy I discovered it when I did. (And I probably wouldnt have even looked if not for the folks here who got me thinking about it)

I encourage EVERYONE trying the SpineCor to get their kids inbrace xrays confirmed by an independent qualified doctor. Maybe I am the only one with what I perceive to be a significant discrepancy. I truly hope that is the case.

CD ...

We don't agree on everything (or at some times ... much at all).

THIS is a point upon we do. For some reason you can bring it up and it's accepted (nevermind I was a braced kid ... and still think a brace is a brace is brace - until I see otherwise).

I also hope the best for those who seek new/alt treatments ... but read the negative as well as the positive.

My kids are older ... although my daughter has a non-progressing lumbar curve (has since ±10 yrs old). It's relatively small (from her films, I gather <30°, but causes her significant pain).

Use your mind, your web search ... and your experts.

Best to all.

Pam

LindaRacine
07-01-2009, 12:11 PM
What the heck, I might as well throw this one up there too.
Anyone see a way that this could be measured as 26 degrees?

:mad:

No way!

And, by the way, to what does the 143 degrees refer?

LindaRacine
07-01-2009, 12:13 PM
I agree, especially about the issue of detecting a change rather than an absolute number.

But I have run into an issue with the inaccuracies of the Cobb measurement. I disagree with one of my daughters (former) doctors about the measurements of her inbrace Cobb. His response is both; 1. it is not uncommon to have different measurements from different people and 2. he picked different vertebrae than myself. (well, there is 3 too: he has a lot more experience than myself)

Using this new ALDT method may reduce the error in (1) above and negate the error in (2) above.

What I don’t understand about the xray process is the effect of the distance between the source of the xrays, the subject, and the film.

Is it like a flashlight, where the beam broadens as the distance increases, ie, one single point source of xrays?
Or,
Is it a uniform source of xrays such that distance measurements are valid?
The official distance set by the Spinal Deformity Study Group is 72".

Ballet Mom
07-01-2009, 12:15 PM
Pam,


Use your mind, your web search ... and your experts.

Great advice. I am very happy with the treatment regime given to my daughter by the orthopedic surgeons we have seen. If they had given in to my internet research and the marketing that goes along with it, my daughter would be in much worse shape. I am happy these very intelligent surgeons are around trying to help people.

txmarinemom
07-19-2009, 11:53 PM
What the heck, I might as well throw this one up there too.
Anyone see a way that this could be measured as 26 degrees?

:mad:


CD, I just saw this alleged 26° x-ray. Compare it to my ±53° one listed in my sig. My POST-op is <20° for your reference (same set of progression films) ...

I think I'm not telling you anything you don't know :(.

Pam

Pooka1
07-20-2009, 06:33 AM
I am guessing CD's experience is no isolated incident.

Surgeons, at least some and maybe most, dismiss the Spinecor literature for a reason.