Thursday, August 19, 2010

Comparison of Epiphyseal Distraction versus Lateral Joint Loading

Previously, I've written about epiphyseal distraction before and how it was found to only increase growth rate and not actually increase "final" adult height.  If the slides of epiphyseal distraction versus slides of rats under LSJL were compared, we could see if there were any differences like signs of mesenchymal stem cell recruitment.  And if you look at Slide B, you can see tiny white cells coming down from the bone into the cartilage. 

I asked Hiroki Yokota about it and he said the results are consistent throughout all mice. "This is a mouse study and the images are representative.  We conducted histomorphometry (measurements of thickness, #cells, etc.) and statistical tests.  Therefore, the results are evidence based and statistically significant." One thing I've noticed with inquiring experimenters is that they are willing to answer questions about experiment methodology but aren't willing to offer their opinions as to conclusions.  I can understand why for fear of being quoted for their opinion to use the authority of their research status.

All the slides are from the study: "Limb Lengthening by Distraction of the Epiphyseal Plate: A comparison of two techniques in the rabbit."  The study explains epiphyseal distraction: "[The method] of distracting the epiphyseal plate employs smaller forces and/or a slow rate of distraction with the intention of inducing an increase in the activity of the growth plate without causing either fracture or gap. Thus the functional integrity of the plate is maintained until the end of the physiological growth period. In 1979 De Bastiani, Aldegheri and Renzi Brivio introduced the term chondrodiatasis to describe this slow, controlled and symmetrical distraction of the epiphyseal plate without fracture or rupture."

"Group 2: chondrodiatasis. After 7 and 14 days of distraction, an increase in the height of the growth plate was observed, but the line of the growth cartilage was regular (Fig. 6). The bridging cartilage appeared to be slightly hyperplastic with modest changes in the columnar architecture limited to a few points in the epiphyseal plate.  There was no evidence of detachment of the epiphyseal nucleus, nor of any haemorrhage (Fig. 7).

By day 28, at the end of the period of distraction, the lengthened portion was occupied by ossification tissue
similar in appearance to that of the metaphyseal bone of the control femur. The appearance was not uniform,
because of brownish zones which were areas of tissue undergoing ossification. The line of the cartilage showed normal morphology, but at some points it was markedly thicker. At the periphery of the plate there was an increase in the thickness of the periosteum without gaps in the perichondrium.
 
The bridging cartilage in the zones of increased thickness displayed marked hyperplasia and hypertrophy, with some disorganisation of the columnar structure but no evidence of cellular damage (Figs 8 to I I).  Histological specimens taken on day 50 and day 70 showed an active epiphyseal plate which had returned to normal thickness (Fig. 12). Cellular morphology confirmed the normal organisation of the growth plate and adjacent elements, matching that of the control limb[The control limb was one undergoing distraction osteogenesis in the epiphysis]."



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The growth plate 7 days after performing epiphyseal distraction.  Can't see the incoming cells like in LSJL.

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28 days after epiphyseal distraction.  The blue line is the hyaline cartilage growth plate line. The red looks like blood flow but the study claimed no sign of hemorrhage.  Blood flow is very anabolic though!

So, evidence of a hyaline cartilage growth plate line after "fusion" and differences between LSJL and epiphyseal distraction.

Here's a normal growth plate:

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Here's the "fused" bone after distraction osteogenesis:

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The blue line is still there.  The idea behind LSJL is to get stem cells or periosteal progenitor cells to this blue region and then in there the stem cells will undergo differentiation into chondrocytes and endochondral ossification will begin.  Here's what happened when the performed distraction osteogenesis on the growth plate cartilage:
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The parts of the cartilage that turned into bone remarkably correlates with the blood splatters.

5 comments:

  1. Tyler
    How did the scientists perform epiphyseal distraction? So your hypothesis is that LSJL is more effective since it recruits stem cells? Thanks, Pete

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  2. ^^^ I believe that's the conclusion Tyler has come to Pete.

    I'm more concerned about the side effects of lsjl.
    I still can't get past how loading your joints qith heavy weight/tapping them wouldn't cause them any harm
    How often do you perform lsjl Tyler? Everyday? How long per session?

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  3. I know tyler has the most information and experience about lsjl, but I wouldn't be so concerned about damage. If you feel like your legs are sore, stop until they don't. I feel achy/pains, not sure if "growing pains" days after if I stop for a while, but to me it feels good, like there is growth happening. Sometimes I will do multiple days in a row, or then one day on/one day off. If microfractures heal quickly, then there shouldn't be a huge worry about damage to the bone itself. The feelings/sensations may be of a chemical nature as well, and could be a good thing. I used to skateboard daily, and really put major strain on my ankles, knees and back, which I'm sure a lot of people have doing other sports. Just do it and listen to your body!

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  4. ^^^^Slimchanse

    I usually have a pain on the inner part of my left pain every time i try lsjl.
    It is actually preventing me from doing it for longer than a week at a time.
    Im not sure if im doing it wrong or what
    Its like the bone feels sensitive or something afterword, and it is also sensitive to the touch.

    Have you had any increase in height?
    If so, or even if not, what is your routine?
    weight, time, sets, etc
    thanks

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  5. Sometimes when I put the dumbbell on my ankle it will really hurt, could be that I have it on a tendon, so I adjust it or push on my ankle to move the tendon around...sounds funny, but it works. Yes, my skin feels sensitive right after. The next morning my legs, from the knee down feels achy, like you know you have walked a lot or something, could last for days, but is definitely bearable. I will do multiple sets w/ 65 lb dumbbells. I am not using a hex shaped dumbbell, so I have less surface area than that, probably 2" in dia. I will get it right on the epiphysis or sometimes more on the cartilage below it. I will do it for one minute at a time, then maybe a few more sets at 30 seconds. I will do my first set on both ankles w/ a piece of wood on the carpet to make sure there is no cushion. Then I will do it directly on the carpet. There is a huge difference. I also do 30 taps before lsjl above the epiphysis. I am trying to experiment w/ what Tyler has showed/explained. My height increase seems to fluctuate. I am 5'7" and at times it looked like I was up to 5'7 3/4", but I measure often and I have gained at least 1/4". There is more to it as far as the physiological side of your body to optimize lsjl as well.

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