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flerc
04-01-2013, 11:42 PM
The Hueter-Volkmann principle is the cause (not the only one for me) of the scoliosis vicious cycle, because more pressure on growing bone of the concave side provokes less growth than in the convex side (without great pressure), so an increment of the curve would be the outcome, leading to more pressure on the concave side.. I suppose this principle has nothing to do with adults.

But not the Wolff's law “Bone is rebuilt more if there are stresses on the bone, less if there are not. (1892”) wich is more complex and I don’t know if is something opposite. Maybe someone here with enough Biology (Osteology?) knowledge may explain me this.
It seems that ‘rebuilt’ includes changes in geometry shape. It seems that may be (in opposite to H-V principle) something good.
I don’t know if this may be true and why: ‘The continual asymmetrical loading of the vertebrae leads to permanent bone deformity via the Hueter-Volkmann principle and Wolff's law.’ http://www.squidoo.com/scoliosis-brace
Why the Wolff's law provokes a permanente deforming? Because less pressure in convex side will turn it weaker? But the conflictive side is the concave side, which would be rebuilt because a higher pressure, not deformed. Probably this law works in all the bone, not only in differents parts as the H-V law, but anyway why should to provokes a deformity? Because an unequal pressure avoid a rebuilt? Or leads to a bad rebuilding? I don’t understand.

‘For centuries, the scientific equipment did not exist to prove that bone remodeling applied to adults as well as children. As a result, the medical community inappropriately applied the physics of the law to children only, as it was believed that bone modeling stopped when a person reached skeletal maturation. However, since 1990, medical evidence has shown that Wolff’s law extends to adults as well. (ref. 4) So, while the medical community has for years accepted bracing for children, the evidence for bracing to be accepted for adults is now clear -- the physiologic principles are the same.’ http://www.prcstudiocity.com/scoliosis.html
‘These results suggest that if appropriate loads can be applied to human vertebrae, scoliosis with vertebral wedging can be corrected without a spinal fusion in both adolescents and adults.’ http://europepmc.org/articles/PMC3086537/reload=0;jsessionid=BymLKZ91Sf7fxWA0MwTD.0

The first time I heard about this law some years ago, I imagined that scoliotic people with a flexible spine should to stay lying down with the soles on a wall and someone pushing the shoulders against the wall, so in this way, the aligned vertebras (because the absence of gravity force) would suffer a similar pressure as normal people standing up.
This idea of the use of braces tends to do the same.

“Remodeling is triggered not by principal stress, but by "flexure." And it seems that Wolff’s law has an umbral of flexure force and below it, none rebuilding is done.

So, what I want to know is if in scoliotic people, rebuilding not works because unpair forces in concave/convex sides or because flexure force is lesser (because gravity force descomposition), under the umbral. If the answer would be the first, I'm not sure if more pressure in the concave side not would turn it stronger. If it would be the last, braces would not be necessary for rebuilding, but just only more pressure (jumping, lifting weights..)

I hope someone here may help me with these doubts. To talk with physicians (surgeons, osteologists, rheumatologist..) about these issues is only a waste of time.

leahdragonfly
04-02-2013, 09:15 AM
Hi flerc,

I would be extremely cautious about relying on the following link that you cited:

http://www.squidoo.com/scoliosis-brace

If you read that entire article you will see it is one huge, shameless promotion for the CLEAR institute, hardly the paragon of virtue or knowledge by any means.

Good for you for trying to understand more about the mechanics of scoliosis if it interests you. You will have much better luck looking for scholarly articles somewhere like pubmed.

flerc
04-03-2013, 03:15 PM
Hi Leahdragonfly, I hoped your reply. Certainly, as is usual for me, I felt alone without people interested in these issues. Thanks!!.

I knew that link belongs to Clear, but when I’m thinking in something "new", they often seems to be using it.
I found this Pubmed link http://www.ncbi.nlm.nih.gov/pubmed/20543392 but I do not be sure if I’m understanding it. I hope you may help me. I have read that since 10 week old a Sprague-Dawley is an adult, so (probably because my English) I don’t understand this: ‘The growth rate of the loaded vertebrae as a per cent of control vertebrae was 60% in Group 1, 40% in Group 2, and 30% in Group 3.’ As I know, by definition adults don’t growth. Their bones do not grows any more.
Anyway I suppose that is true that during growth, Wolff's law may lead to a vertebra deformation. May be it also true after growth (adults)? Also may be possoble to get correction in adults? Why they said this?: ‘scoliosis and vertebral wedging can be corrected without a spinal fusion in both adolescents and adults’. Of course is something different to minimize a deformation that getting a correction. Certainly after read this article I’m more confused. I need to know if the exercise I imagine some years ago would be really useful or only dangerous as I suppose it is all what I imagine.

Thanks in advance!

flerc
12-29-2013, 01:58 PM
I'm almost sure (99.99%) it was the external fixation, the russian method, what I saw in a Discovery channel chapter, used to make 30 cmts taller an dwarf adult. The bone was slowly regenerated IN AN ADULT!.
Nobody else is interested in this issue?

Pooka1
12-29-2013, 06:54 PM
I'm almost sure (99.99%) it was the external fixation, the russian method, what I saw in a Discovery channel chapter, used to make 30 cmts taller an dwarf adult. The bone was slowly regenerated IN AN ADULT!.
Nobody else is interested in this issue?

You have to ask why researchers aren't interested in this issue (if they aren't), not why us bunnies aren't interested.

flerc
12-29-2013, 09:49 PM
Instead of talking about bunnies or saying what someone here should to ask or not, try to be at least something honest, something valiant and reply what I said about your illogic claims in other threads. You have a lot of them to choose.

hdugger
12-29-2013, 11:08 PM
May be it also true after growth (adults)?

Based on the article you quoted earlier - http://europepmc.org/articles/PMC3086537/reload=0;jsessionid=Via51jbxs9OdAAc4hK90.4 - yes, they think remodeling works in adults, only more slowly.

"Although nonfusion operative correction of AIS is be best suited for young patients with small curves, it may also achieve correction of large curves in older patients via the process of remodeling of the vertebrae and ribs over a longer timeframe."

flerc
12-29-2013, 11:24 PM
I'm almost sure (99.99%) it was the external fixation, the russian method, what I saw in a Discovery channel chapter, used to make 30 cmts taller an dwarf adult.


Yes it was http://www.shortsupport.org/Health/Leg-Lengthening/procedure.htmlYes
It seems they did this distraction procedure in the vertebras of that girl http://europepmc.org/articles/PMC3086537/reload=0;jsessionid=BymLKZ91Sf7fxWA0MwTD.0 (figure 5)
Am I not understanding something or it really seems that in Russia there is a non fusion surgical solution for adults?

flerc
12-29-2013, 11:36 PM
Based on the article you quoted earlier - http://europepmc.org/articles/PMC3086537/reload=0;jsessionid=Via51jbxs9OdAAc4hK90.4 - yes, they think remodeling works in adults, only more slowly.


Yes, if bones can growth in adulthood, something always considered impossible, bone remodeling in adults is a fact.

hdugger
12-30-2013, 12:16 AM
Am I not understanding something or it really seems that in Russia there is a non fusion surgical solution for adults?

I'm not sure how old the patients are. The one girl in the picture looks like a teen, but they're also talking about very large (around 90 degree) stiff curves. So, yes, maybe it would work for adults as well.

But, sort of, Yikes! The procedure seems pretty invasive and they are leaving some kind of internal structure inside:

"The surgical procedure consisted of two stages, anterior and posterior approach, dissectomies, vertebrectomy at the apex, spinal column shortening and the placement of an external stabilization device. Progressive correction of the curve was done by a daily increase in distraction (3 mm/day). When the correction was finished, a different internal fixation device was used to maintain the correction. The time between initial treatment and final correction was 50 days."
http://europepmc.org/abstract/MED/15996611

I'm not necessarily following all that well, but it sounds like they're *surgically* remaking the spine (a bunch of ectomies and then spinal column shortening, whatever that is) and *then* they're placing the external device and slowly cranking it straight for a few months. And then they're leaving something behind - I assume permanently "a different internal fixation device was used to maintain the correction".

So, I guess I'm not sure that there's actual non-surgical remodeling going on. It sounds more like they're doing surgery to remodel the vertebrae and then using the external device to stretch the ligaments etc.

flerc
12-30-2013, 01:04 AM
Surely you are right Hdugger, certainly I cannot imagine that with only giving to the vertebras a perfect shape, the scoliosis would be vanished. When my daugher was lying down over her curve (over her left hip and left shoulder) I saw her spine aligned. I may imagine a magical transformation over her vertebras, but instinctively, intuitionally, I'm sure her curve would appears again when she stand up again. Fascias, rib cage, ligaments, muscles, tendons, nerves, discs.. surely would need an important adaptation too.
The teen (in those days) daughter of a friend had a very much bold surgery fixing only some vertebras. He was aware about the risk and certainly when she stood up, all her trunk (including the head) bended to one side. She walked for a time in that way but after some days her spine remained straight until today. Her vertebras were the same, but sure all other tissues suffered an adaptation.

But anyway it seems that a non fusion surgery for adults and for big curves would be avaliable in Russia, something surely without precedents.

flerc
12-30-2013, 01:20 AM
Anyway, in a non surgical way, adult bone remodeling also seems to be possible:


http://www.orthopectus.net/index.php?option=com_content&view=category&id=3&Itemid=4
01. How does this procedure work? We have always been told that the position of the ribcage can not be altered non surgically, because pectus is a combination of excess bone and cartilage infused in a solid state.

Nicolas Andry, the man considered the "Father of Orthopaedics," in his book L’orthopédie ou l’art de prev’enir et de corriger dans les enfants, les difformités du corps, published in Paris in 1741, observed that limb deformities could be corrected through conservative methods of treatment. Later, Julius Wolff described what is accepted as a law in Orthopaedics: "The bone tissue is a dynamic structure that can be remodeled according to external forces." What we have been doing is using these concepts to correct pectus deformities. Despite being solid, bone and cartilage are live substances that have the capacity of remodeling. The younger the patient the greater is his/her potential for osteocartilaginous remodeling, but such a remodeling occurs throughout life.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2532136/

If it works with pectus deformities.. why not with spine deformities too?..http://www.orthopectus.net/index.php?option=com_content&view=article&id=27:10-what-can-be-done-if-the-pectus-patient-also-presents-a-scoliosis-lateral-curvature-of-the-spine&catid=3:faq-&Itemid=4

hdugger
12-30-2013, 01:27 AM
But anyway it seems that a non fusion surgery for adults and for big curves would be avaliable in Russia, something surely without precedents.

I sort of recall Betz doing something similar at around the same time. He went in and remodeled some of the vertebrae surgically. I'm not sure if he did anything else. But I haven't seen him follow up on that, and Lenke was expressing a good deal of doubt about it working.

hdugger
12-30-2013, 01:37 AM
I sort of recall Betz doing something similar

Here's Betz's article:

http://www.ncbi.nlm.nih.gov/pubmed/14560202

He did the research on paralytic scoliosis but said that it might one day be applied to idiopathic. But, he didn't do anything other than the remodeling.

This link has Betz again and he describes the operation a little better (it also involves the placement of a temporary internal rod), and Lenke's response (you have to put your mouse over Lenke's name to see his response). Lenke is calling the wedge osteotomies "challenging and controversial," but he's not completely ruling them out.

http://www.spineuniverse.com/conditions/scoliosis/new-surgical-treatments-scoliosis-vertebral-body-stapling-wedge-osteotomies

leahdragonfly
12-30-2013, 09:23 AM
This sounds like a pretty extensive spine reconstruction with hardware left in, followed by at least a 50-day period of having a massive external-fixation contraption coming out of your back. You would not be able to lay down, or wear clothes very easily, and would surely be susceptible to bone and wound infection. This contraption looks very scary to me in the photos as well as painful. I don't love being fused, but I really have to wonder what this procedure would save over a fusion, especially when they are talking about people with 80-90 degree curves, being able to only reduce them to 40-50 degrees at best.

May be an interesting idea, but we're definitely not there yet.

Pooka1
12-30-2013, 10:03 AM
It appears to be in lieu of halo traction. It appears to be ambulatory traction. They do an anterior release (remove discs) just like they do ahead of halo traction.

After this procedure and halo traction is a definitive fusion. That is what is referred to as internal fixation in my opinion.

Now it is up to the individual if they want to be in halo traction or have this ambulatory traction prior to fusion. That is for each person to decide.

hdugger
12-30-2013, 11:16 AM
for each person to decide.

The point of the Russian article was the period of bone remodeling with external fixation per Flerc's question about bone remodeling in adults. He wanted to know if remodeling could take place in adults, and that paper suggested that it could.

For surgical (not natural) remodeling, one can look at the (experimental) surgical remodeling without fusion, as described in the Betz article I cited earlier or this one:

http://www.ncbi.nlm.nih.gov/pubmed/16985458?dopt=Abstract&holding=f1000,f1000m,isrctn

which only require the osteotomies without either traction or fusion.

Pooka1
12-30-2013, 11:56 AM
That article does not appear to be about bone remodeling. They are removing discs and applying distraction ahead of a definitive fusion. Apples and oranges to bone remodeling.

flerc
12-30-2013, 01:47 PM
Everything around adult bone remodeling is confusing for me. But after seeing yesterday the Discovery tv program, I understand is definitely a fact. Adults bones shape may change in a natural and better way, they also can growth, something apparently imposible. Is a very good news really. We can use Wolf's principles in a non surgical or surgical way. External fixation is the surgical procedure used in adults bones, massively in legs of short stature people. It seems in Russia they used it for remodeling vertebras as I understand. Certainly if it would be possible to the same to what they are doing in legs, it would be possible to remodeling vertebras, it also would be possible to have bigger vertebras so it could be another way to be taller.
I don't see where they says that some hardware remains inside but it would not surprids me, anyway it seems there would not be a lost of flexibility, not?.

hdugger
12-30-2013, 02:41 PM
Everything around adult bone remodeling is confusing for me.

Dr. Sucato feels your pain and would like to help :)

Here's part of a very interesting roundtable I ran across (addressing just growth modulation and comparing between leg and spine):

"Sucato: Growth modulation has been extremely effective primarily in the lower extremities where we have a clear understanding of the physes or growth plates with respect to their direction and the rate of growth. We know that the distal femoral physis grows at a rate of approximately 9 mm/year while the proximal tibia grows at approximately 6 mm/year. However, spine growth is much more sophisticated since there are growth plates at the ends of the vertebrae as well as growth plates at the base of the pedicles (neurocentral synchondroses).

Despite this, tethering devices have been utilized and have shown promising results in the spine, especially in animal models. . . . Growth modulation requires a surgical procedure and carries some risk for complications, especially because they are placed through an anterior surgical approach. There is also an unknown long-term outcome of the implants. Unlike any other implant in the spine utilized for spine deformity, these implants will always be between motion segments that are not fused and the possibility for migration is prsent. We continue to study the concepts of growth modulation at our institution and are excited to continue to investigate this technique to the point of utilizing it clinically.

flerc
12-30-2013, 05:40 PM
Great Hdugger, thank him for me :)
Certainly it seems to be something very new.. and Russia is very far from my country..
In fact I'm interested in principles and surely they might be used in a more simple and safe way, something as done with DR method.
I think Wolf's law talk about the intelligence of the body. Bones get the transformations required by circumstances. If more consistence is needed they turn more consistent if they need to grow, they grow. Great!

flerc
12-30-2013, 10:52 PM
Certainly I'm not sure if allways bones seems to be intelligent.
To growth in adulthood is the way to repair the broken zone when distraction forces are applied in that zone. Is a good behaviour in front of a difficult situation, but I heard that vertebral wedging in an adult curve never stop and if effectively it is true (is it?) it'd not seems to be having a right behavior in that case. Wolf's law should lead the concave side to be more consistent, because the pressure is greater in that side, so why the wedging? I only can imagine a distraction effect in the convex side.

flerc
12-30-2013, 11:08 PM
Distraction was the main principle used in braces of other times, certainly in the super brace used centuries ago, when braces were not seen as a mysterious artefact coming from who knows where. It'd not surprise me if it provoked a major growth in the concave vertabra side. In the way that forces were applied, I think were greater in the concave side. But gravity force apply forces exactly in the opposite way, and certainly we may talk about a distraction in the convex side.
And remodeling never stop, so it would be happening an 'external fixation' effect in that side, leading it to growth, and then incrementing the difference with the concave side.
I'm right? I really hope to be saying something without any sense.

aterry
01-13-2014, 05:39 PM
Flerc, I'm very interested in this topic. I don't have much of a scientific mind so I don't have analysis to add. But I follow your reasoning and your questions and I agree with your train of thought. When ever I come across articles on this topic I read them. I also read about tissue scaffolding--but I think that will take decades before it could possibly be of use to scoliosis patients. I discuss these approaches with the few people I know who are interested--a physical therapist, for instance. It seems that most doctors are set in their ways and don't really follow new areas of research--at least the surgeons don't. Accept for which screws to use, or which rods. Which I'm sure is ultra important but beyond surgery they really don't care. I think there is less research in this area because there's less money to be made from therapeutic approaches that might come out of it. Also, I think there's less research on scoliosis, in general, because the majority of new on-sets are teenage girls and that is a throw-away population in the US. Until we get a multi-billionaire who's daughter has scoliosis we're going to get no where. I understand that CLEAR, and their ilk, are considered hocus-pocus outfits but where are the substantive institutions that are offering hope of ANY kind?

flerc
01-13-2014, 07:00 PM
Aterry! What a good news and coincidence!. Yesterday I was trying to remember your user name when I was rembering all the good people of those times.. too few still here.
I don't know if you don't have much of a scientific mind, you may have it even without a good science background, but without any doubt you have common sense, criteria and logics to analyze that kind of problem. Expert knowledge is needed to get right conclusions and in these days decided to consult an osteologist who really wants to help people, not only to follow the protocol!. Is a great discovery I did some years ago, I hope she may know enough about this issue, but I think that physicians are something as technicians, knowing only about the work they must to do. I know she don't know about tissue engineering, but should to know enough Wolf's law. Certainly this kind of bone remodeling is done by the body in a natural way, so they should to know, but probably only researchers kows about these issues. We need to know about someone in this area.
How is your daughter? Very sad what you says about teenage girls in USA, but probably is the same in every country.. medical decisions are hard to understand and anyway we live in the medical surgical age. This forum is realy according to it.
We stay in contact!

Victine
01-14-2014, 06:40 PM
Until we get a multi-billionaire who's daughter has scoliosis we're going to get no where

Or just a determined Scottish father of reasonable means . . . . . who is getting somewhere.

flerc
01-14-2014, 09:16 PM
Yes, another chance really.

flerc
01-14-2014, 10:05 PM
Distraction was the main principle used in braces of other times, certainly in the super brace used centuries ago, when braces were not seen as a mysterious artefact coming from who knows where. It'd not surprise me if it provoked a major growth in the concave vertabra side. In the way that forces were applied, I think were greater in the concave side. But gravity force apply forces exactly in the opposite way, and certainly we may talk about a distraction in the convex side.
And remodeling never stop, so it would be happening an 'external fixation' effect in that side, leading it to growth, and then incrementing the difference with the concave side.
I'm right? I really hope to be saying something without any sense.


Distraction occurs in muscles across the convex spine side (also ligaments?), so those belonging to that side are larger, but I'm thinking that surely, the force that paraspinal muscles may does in order to keeping adjacent vertebras together, are absolutely uncomparable with what external fixation does. I don't know if some ligaments also are keeping adjacent vertebras close (but surely the same as about muscles may be said) and surely has not any sense to suppose that discs are doing that kind of cohesive force that effectively exists after a vertebral surgery as Vbs or fusion.
So I suppose that in a spine with none surgery done, an external fixation effect is not possible.. but what may I know?..

Although distraction in vertebras surely was also not possible in the super brace of other times, it seems that (because other reasons) the spine distraction acheived in those times was very much effective. It seems to be unfair it was avoided in current braces conception.

mariaf
02-22-2014, 03:09 PM
aterry,

I sent you a PM.

Pooka1
02-24-2014, 06:10 PM
Until we get a multi-billionaire who's daughter has scoliosis we're going to get no where.

Not a "multi-billionaire" but Madonna is either the second or third richest woman in the UK (the other being J.K. Rowlings and the richest being Queen Elizabeth II) last I knew. Her daughter, Lourdes, has been spotted wearing a Spinecor brace.

http://scoliosisnutty.blogspot.com/2009/07/madonnas-daughter-scoliosis.html

It would be interesting to ask if Madonna is funding scoliosis research.

mamamax
04-05-2014, 10:55 PM
Interesting topic. Looks like one is never too old for a little bone remodeling - and that's good news for me at 64 ...

http://www.sciatica.org/downloads/YogaOsteoporosis_PilotStudy.pdf