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  • Bone Remodeling

    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/PMC308...Sf7fxWA0MwTD.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.

  • #2
    readers beware

    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.
    Gayle, age 50
    Oct 2010 fusion T8-sacrum w/ pelvic fixation
    Feb 2012 lumbar revision for broken rods @ L2-3-4
    Sept 2015 major lumbar A/P revision for broken rods @ L5-S1


    mom of Leah, 15 y/o, Diagnosed '08 with 26* T JIS (age 6)
    2010 VBS Dr Luhmann Shriners St Louis
    2017 curves stable/skeletely mature

    also mom of Torrey, 12 y/o son, 16* T, stable

    Comment


    • #3
      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!
      Last edited by flerc; 04-03-2013, 02:19 PM.

      Comment


      • #4
        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?

        Comment


        • #5
          Originally posted by flerc View Post
          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.
          Sharon, mother of identical twin girls with scoliosis

          No island of sanity.

          Question: What do you call alternative medicine that works?
          Answer: Medicine


          "We are all African."

          Comment


          • #6
            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.

            Comment


            • #7
              Originally posted by flerc View Post
              May be it also true after growth (adults)?
              Based on the article you quoted earlier - http://europepmc.org/articles/PMC308...s9OdAAc4hK90.4 - 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."
              Last edited by hdugger; 12-29-2013, 10:11 PM.

              Comment


              • #8
                Originally posted by flerc View Post
                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/L...cedure.htmlYes
                It seems they did this distraction procedure in the vertebras of that girl http://europepmc.org/articles/PMC308...Sf7fxWA0MwTD.0 (figure 5)
                Am I not understanding something or it really seems that in Russia there is a non fusion surgical solution for adults?
                Last edited by flerc; 12-30-2013, 08:52 AM.

                Comment


                • #9
                  Originally posted by hdugger View Post
                  Based on the article you quoted earlier - http://europepmc.org/articles/PMC308...s9OdAAc4hK90.4 - 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.

                  Comment


                  • #10
                    Originally posted by flerc View Post
                    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.

                    Comment


                    • #11
                      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.

                      Comment


                      • #12
                        Anyway, in a non surgical way, adult bone remodeling also seems to be possible:

                        Originally posted by flerc View Post
                        http://www.orthopectus.net/index.php...&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...:faq-&Itemid=4

                        Comment


                        • #13
                          Originally posted by flerc View Post
                          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.

                          Comment


                          • #14
                            Originally posted by hdugger View Post
                            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/conditi...ge-osteotomies

                            Comment


                            • #15
                              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.
                              Gayle, age 50
                              Oct 2010 fusion T8-sacrum w/ pelvic fixation
                              Feb 2012 lumbar revision for broken rods @ L2-3-4
                              Sept 2015 major lumbar A/P revision for broken rods @ L5-S1


                              mom of Leah, 15 y/o, Diagnosed '08 with 26* T JIS (age 6)
                              2010 VBS Dr Luhmann Shriners St Louis
                              2017 curves stable/skeletely mature

                              also mom of Torrey, 12 y/o son, 16* T, stable

                              Comment

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