Me: I have been having this issue for the longest time with any method or technique that does not involve at least comes kind of  distraction in the bones we want to stretch and lengthening because I have been having the hardest time wrapping my head around how such methods could possibly work. I have talked to my coworker about this and Tyler but the answer was always “chondrogenesis” which I couldn’t understand. Finally I decided to send Tyler an email so he can clarify what that means. Also, I wanted to ask him about this specific issue when applied to his method, the LSJL, and why it works.

Questions

Inbox…

Natural Height Growth, naturalheightgrowth@gmail.com,  to Tyler,  Sep 30 (2 days ago)

My coworker and i are having a discussion on a main point. how is lsjl able to break apart and stretch out the hard inorganic calcium phosphate bone matrix of the cortical bone even if chondrocytes are being created at such a high level. it should not do anything since you are pushing against something that is harder than concrete.

Tyler Davis to me, Oct 1 (1 day ago)

LSJL doesn’t try to push apart the bones.  LSJL tries to induce chondrogenesis in the epiphysis of the bone.  The chondroinductive properties of LSJL have been validated by gene expression results and histology diagrams.  The ability for hydrostatic pressure, fluid flow, and LIPUS to induce chondrogenesis of adult human MSC’s has also been validated in vivo.  LSJL induces similar stimuli as HP, FF, and LIPUS

Natural Height Growth naturalheightgrowth@gmail.com, to Tyler,  2:12 AM (19 hours ago)

i still don’t get how creating more cartilage cells in the epiphysis will lead to longitudinal growth. even if this type of external stimuli is inducing the right type of genes to produce and release the right type of protein, how can they get around the hard bone? the epiphysis may not be as hard as the diaphysis but it is still very strong.

People keep telling me that the answer is in the chondrogenesis like her but I can’t figure it out. Here is my thinking…

1. So you produce a lot of chondrocytes from MSC differentiation in the cancellous external cavity in the epiphysis ends….

2. The loading (assume it is lsjl method) causes certain genes in the MSC and other HSC in the bone marrow to up regulate and release growth hormones and increase rate of changing into the right type of

3. Some BMPs, FGF, and maybe some other growth factors which are proteins and hormones increases in formation and output or gets turned on

How does the epiphysis increase in length? I realize now that my focus or at least what is easier for me to understand is the orthopedics part, less of the endocrine stuff, and least of all the genetics stuff. So I am focusing on the orthopedics right now.

You say that you are trying to induce the generation and proliferation of chondrocytes in the inner cavity of the epiphysis. How does the chondrocytes then make the overall bone longer? The epiphysis still has a very hard surface so the cell should not be able to pass through the outer bone but then it has the peristeum to deal with. If you remember, the growth plate passes completely through the long bone for it to separate the two bone parts further from each other.

The only explanation I can think of is that you are assuming that the constant rate of osteoblast and osteoclast formation and resorption on the outside and inside might get the inner produced chondrocytes to be pushed out of the inner cavity and once it reaches close to the surface, it causes a bone lengthening process similar tot eh growth plate. However, growth plates have chondrocytes stacked neatly on top of each other. Please explain the process because I am stuck over and over again. the science from a engineering and physics point of view makes no sense.

this is the same kind of problem i am having with fully understanding the ilizarov method. I am still confused whether the fracture is made completely through the bone, thus opening up to the bone marrow cavity or is it just the outer dense bone that is cracked open.

maybe i am being really stupid here so call me “billy bob” but this one part makes no sense.

Tyler David to me, 2:43 AM (19 hours ago)

The principal is that cartilage is capable of growth from within whereas bone is not.  Growth plates have to be capable of pushing incredible amounts of weight like an elephant for example.  Bone can only grow on the outside whereas cartilage is capable of interestitial growth.  Therefore the growth plate doesn’t have to be completely from one end to the bone to the other.  The periosteum is capable of lengthening as well.

If you look at this picture of a finger fracture: http://www.heightquest.com/2010/02/empirical-evidence-of-possibility-of.html.  You can see that my finger increased in length(diagonally) without the whole finger being broken.

And LSJL increases matrix degradation via MMP3, MMP2, and MMP14.  Thus addressing the cortical bone problem.

Growth plate chondrocytes are often not stacked neatly on top of each other.  Also the epiphysis is porous with trabecular bone.  It has a lot of empty spaces filled with marrow.  Yellow/Red doesn’t matter because adiposal stem cells are capable of chondrogenic differentiation too.

Cartilagenous growth plates are capable of interstitial growth.  Growth plates always work against force as it is trapped between two bone ends.  Thus, growth plates should be able to generate growth from within a bone.  One issue is that static compression decreases growth plates and as you say bones are heavy.  So after inducing chondrogenesis with say LSJL it may be best to use microgravity afterwards say inversion or just giving your legs a break for an hour.  Inversion is hard to do for long periods of time though.

In summary: Growth plates can beat forces by definition as they are always trapped between a rock and a hard place(epiphysis and diaphysis).  The sides of the bone are just another force.

Feel free to include this conversation as a “guest post” just include the backlink.

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Natural Height Growth, naturalheightgrowth@gmail.com, to Tyler, 1:30 PM (8 hours ago)

Okay. Now I am finally starting to reach some kind of understanding on what you mean. However, there is still two small points that I haven’t figured out yet.

1. So you increase the chondrocytes. The chondrocytes release the collagen type ii and proteoglycan which is supposed to form a cartilage matrix.

Am i supposed to assume that cartilage is being formed in the epiphysis cavity from doing these loadings?

If you say yes, then the problem is that I have never heard of an incidence where cartilage is actually being formed inside the marrow cavity.

I have always thought that it requires chondrocytes and cartilage matrix to push apart bone, not just chondrocytes. don’t you need cartilage matrix to push the bones.?

in principle and theory, your idea does make sense.

From a physics point of view, if you can get the chondrocytes to multiply, and multiply some more , they will push. The forces produced in the epiphysis will defintiely increase the hydrostatic pressure.

However the force/area which is pressure on the surface area of the saivty will be divided and distributed across the entire thing.

We both know that long bones have high compressive force and tensile strength so force exerted on the axis directions will have to be large. You are pressing laterally from the inside and they say the pressure needed at least from the outside inwards direction is only 50 MPa.

I am visualizing a picture of the femur in my mind as a cylinder with two spheres on the end, like a dumbbell shape. the cortical bone will be strong so the forces there won’t do much. Nature wants to take the path of least resistance so the hydrostatic pressure and chondrocytes will try to put a stretch on the area which is the weakest, which should than be in the epiphysis, but in the lateral direction.

With my logic, this means that LSJL should make the epiphysis ends wide, but only a little bit longer in on the axis which we want, which is longitudinally. Your theory makes sense but the affects will be so small like an exact few millimeters in long bone lengthening.

2. The other main concern which I see is that the original growth plates were not encapsulated like the new chondrocytes. I agree that the original growth plates did have a lot of pressure exerted on them. growth plates are only a few millimeters and they have to support and hold up a 200 lb person so there is a lot of force/ sqr inch. they are pushing up and down. but the sides are not clamped shut.

I will say this again, the chondrocytes produced are pushing in a closed system which is surrounding by upwards of 1 cm thick of bone that is concrete in strength. and the way the pressure will force upon the inner ways will be distributed in a way that goes towards the weaker epiphysis sides.

I stated before that the tensile strength of long bone is 150 MPa. this means the chondrocytes needed to push up to at least 70% of this amount to cause some deformation. They also have to push in the right direction, along the axis. they are trapped in 1 cm thick physically mature adult femur bones.

If I can figure out or calculate how much force/area the original growth plates had to deal with, and it comes out to be anything close to 50-100 MPa then LSJL will definitely work to increase long bones longitudinally. if the values are not close, then I would guess most of the bone changes would be towards increased epiphysis thickness, and very little for real lengthening.  You will get some bone lengthening but little.

I just need to do more research to see what the biomechanical values are of the bones and growth plates. can you explain away my two main concerns?

Tyler Davis to me, 2:01 AM (11 hours ago)

Unfortunately there haven’t been a lot of studies on forces required to lengthen bone or I haven’t come across them.  There’s a study that I mention here http://www.heightquest.com/2011/05/why-does-hydrostatic-pressure-induce.html about mitotic cell rounding and

The idea is that differentiating chondrocytes will automatically secrete matrix.

Unfortunately, I can’t explain away your concerns now.  Ideally we’d need to the growth plates in action live to see what forces they generate.

I have done research myself on the biomechanical forces of the bone and growth plates and couldn’t find very much.

So unfortunately I can’t explain away your concerns at this time.

Natural Height Growth, naturalheightgrowth@gmail.com, to Tyler, Oct 3 (2 days ago)

Okay. I’ll take this conversation and turn it into another post with the back link. It won’t be posted until I get through the protein pathway and endocrinology posts which could take up to 2 weeks. Im just getting around to doing all the reading and research.