Verteporfin: Scarless healing

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There is a relatively old drug which is being trialed for scarless healing. It has had positive trials in mice, and I believe they're working on pigs currently (whose skin is similar to humans)

https://med.stanford.edu/news/all-news/2021/04/drug-enables-healing-without-scarring.html

This could be a relatively large development in limb lengthening. The obvious use for this is with scarless healing of the surgical incisions. But another angle is that this can be used to promote scarless healing of your soft tissues such as your muscles/tendons etc (especially if they're perfoming an IT band release). Scars in soft tissues are one reason for lowered athletic ability and function in limb lengtheners.

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It should work with any surgery, and any injury that produces scars (but the drug has to be administered before the wound heals)

Theoretically though if a scar forms, I think you should be able to surgically remove the scar and then apply verteporfin and it will heal without scarring. Not sure how this would work in vivo but it's possible those who already have scars from LL can go and get this done retroactively.

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You make a good point, with major surgery like LL it may not be possible to use this drug as it blocks the cells from sensing mechanical stress. It may be a situation where a surgeon (probably plastic not orthopedic) would have to go back and reopen the scars and then apply verteporfin - that is if this is even possible in vivo. 

However I disagree that there is no scarring of the soft tissues. For example stretch marks form when your skin stretches too fast for it to grow, which is a form of scarring. And when the incisions are made to insert the rod and to break the bone, there will be inevitable scarring of any soft tissues they have to go through. If you do externals there will obviously be lots of scarring especially where the pins attach. You can't treat these during lengthening but with this as well it may be a retroactive procedure.

As for the ITB, when they release the ITB I imagine it doesn't heal without any degree of scarring. You cannot compare bone to tendons, as bones don't scar when healing whereas tendons/muscles/nerves all do.

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Based on this video by Rozbruch, I feel like there will be damage done to the soft tissues during the procedure itself because they literally drill through your leg for the osteotomy. That will of course produce scarring as those tissues heal.

In fact the reason so many patients experience permanent knee pain when doing internal tibias is because they drill through the patellar tendon to insert the nail I believe (which heals by scarring) and never recovers 100%. I believe for femoral lengthening when they drill into the femur they don't go through any tendons which is why there generally isn't long term hip pain.

As for the ITB, if it is regenerated without scarring, I'm not sure why there would be losses in flexibility. Is there even a process of natural scar reversal in humans?

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Quote from: SirStretchAlot on July 20, 2021, 07:41:12 AM

As with a drill, my bones were sawed clean. After the skin incision, muscles and tendons in the femur were pulled apart like a curtain and released to their original position after the osteotomy is complete.

Ah ok that is good to hear. In that case it should minimize the damage done during the osteotomy.

As for the ITB, Rozbruch in his interview with Cyborg said it grows along with the bone, that's why they perform the ITB release.

So I'm still confused as to why the ITB is causing a loss of flexibility.

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So you are saying even with an ITB release there will be a loss of flexibility, or is that only the case when ITB release is not performed?

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Quote from: SirStretchAlot on July 23, 2021, 07:02:20 AMThe ITB is not "flexible." ITB release allows you to stretch effectively to regain mobility. Not performing ITB release will lead to loss of function for some people. The band will abduct your legs and make you walk like a duck or penguin.

But my question is, even if the ITB band is released why is there a loss of flexibility in the leg? Does the growth of the ITB band not keep up with the bone, therefore leaving the ITB shorter than the rest of the tissues in that segment?

Is this permanent?

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Ah ok gotcha. It was unclear because I thought you meant the ITB is causing the loss of flexibility so I assumed your ITB ends up shorter permanently.

If it's just muscles that cause the loss of flexibility I imagine that isn't permanent since with enough stretching eventually they will grow (due to distraction histeogenesis). Though, if any of the tissues scar during the process that could be a cause of permanent loss of flexibility.

Btw, can there ever be non-union of the ITB? How does that work?

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Well resistance training doesn't cause muscle scarring either

I don't think you understand though, the muscles aren't simply stretching they are growing too: "When gradual distraction forces are applied across the osteotomy, not only the callus elongates but also the soft tissues grow in response to mechanical stress (mechanostat hypothesis). The soft tissue grows pari passu (hyperplasia occurs) and is not just merely stretched. Hence, the term is “distraction histiogenesis.”
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4922221/

My concern was if the rate of lengthening is too fast for the soft tissues, will it scar rather than multiply? I don't really see any papers which address this.

Also do you know if there have been cases of pre consolidation of the ITB? Would they have to re-release the ITB in this case?

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That's good to know about the ITB.

On the first point, we are talking past each other. You are talking about muscle hypertrophy, which is the growth of the cells itself. That is accomplished through resistance training. Hyperplasia otoh occurs during distraction histeogenesis due to the muscle being stretched apart which triggers cell multiplication.

Also the study I posted is of an oral and maxillofacial surgery procedure (jaw elongation I believe) where there isn't really a resistance training regimen.