#Lichtendahl Tsery | Explore Tumblr Posts and Blogs

laora-ryn · 3 years

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why lichtendahl tsery is the coolest character in gundam 00

Or, in which Laura thinks a lot about Lichty's prosthetics. Probably even more than the production team did

look i just love lichty a lot okay

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me, last night: i can't write this post, i have a horrific headache and laundry to fold

me, four hours and almost 4k words later: oops

laundry did not get folded

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so i'm gonna preface this with, while i have two degrees in bioengineering, it's been about 3 years since I was in school, and nowadays I do more assistive tech and hardly any prosthetics. so, pls don't take my word as god or anything, I'm just here with feelings and science that is (hopefully) at least 75% correct

uhh slight content warnings for show screencaps with blood/dying in them?? and discussions of things that would probably be considered body horror

it is under the cut because holy GOD it got long

first of all, i would like to put out that i am so upset that we literally only find out about his prostheses when he's dying. it makes sense for the story and for his character, it just makes me really sad that it isn't explored any further. like, even prosthetic limbs or systems in general are barely touched on after this

Louise has a prosthetic arm in s2, and we see the surgical scars briefly during the party scene, where she's talking with Setsuna, but she turns the subject quickly. So like, all we know canonically about in-universe prosthetics is that they exist, and that they work well enough, and look close enough to real limbs, that they pass to people who aren't looking closely.

But at this point in 2308, Louise having a prosthetic arm is considered the last-ditch effort. The way Saji talks, the idea of regrowing her arm in a regen pod isn't out of the question, if it weren't for her particle poisoning. (I have another soapbox here about the pods, lol) So I feel like most likely, by this point prosthetic systems have kind of fallen out of favor, and the favored med tech is regrowth (so long as you have the $$$$$$$$).

Which begs the question of: how long ago was Lichty injured?

"My parents cashed in their chips in the solar wars," and he was injured in the same explosion. Setsuna's scene at the start of ep1, which we're led to believe is the twilight of the wars - at least in Krugis - is in 2301. So, as a guess, he was injured in the late 90's. He's 21 in 2307, born in 2286, so - 11-13. Prepubescent, or barely starting puberty, when he's caught up in an explosion that blows away half his body.

His parents were elevator engineers, but I have to assume that they were working within the atmosphere, possibly at the base, because catastrophic injuries like this + the vacuum = no chance of survival, definitely not long enough for someone to find him and get him medical help. So, he must've been on the surface. Still, it's a miracle he survived at all

The wiki makes it sound like his entire body is mechanical, and "only his mind" remained (???). Personally, that, uh, makes no sense to me, so here's my personal headcanon on how much of his body survived:

Obviously his right side was blown away, we see that in ep 24. But I imagine for him to have any sort of chance of survival, his heart must've been spared?? Which guided my thought process there. So, he's got a little more than half his chest, a little residual abdomen that probably got swapped out for prosthetics anyway, + his left arm.

Which...leaves us with a 12ish year old kid on extensive life support, who needs a new lung, a new arm, two new legs, a new diaphragm with which to use that new lung, and all new viscera, as well as a body cavity that will support all of those shiny new organs, both in gravity and without.

I headcanon that Lichty's got one of - if not the - most extensive prosthetic systems in the world. That his parents knew they were going into the job with risks, knew they were bringing Lichty (and the siblings I headcanon he had, who didn't survive the attack) into the potential crossfire of the war. So, his parents probably had it written into their contract that if anything happens to their kids while they're on the job, they get all their medical care paid for by the company, and they get the best care available.

I headcanon he's Ukrainian, ie HRL, which doesn't seem like the bloc to pull out all the stops to save a single nobody-kid. But assuming he has extended family who assumed guardianship, they would've been able to call in the contract and get Lichty put back together. (Sounds like a long shot to me, tbh, but obviously he survived somehow.)

So this kid's on life support in a trauma center somewhere, probably in Indonesia or maybe China, considering the HRL's elevator is in the middle of the Pacific. He's got an artificial digestive system feeding the parts of him that are left, he's on a ventilator, he's on dialysis, he's got so many tubes and wires coming out of him that he's half-hidden behind them in the hospital bed.

He's in an induced coma for months before he's anywhere close to stable and the doctors feel comfortable waking him up. And even once he's awake, he's kept in a sterile room because half his surface area is still open wounds and they can't risk infection. Everyone he sees, for months and months and months, is either on the other end of a video or in a hazmat suit.

And of course, even once he's mostly stable with machines substituting for the organs he's missing, there's the matter of rebuilding them.

We've got just a couple shots of his prosthetics - honestly, not a lot to go on, but here's the three I'm looking at:

(last image from this post by pwryyynce)

So, what I'm seeing here is that his musculature and bone structure are all made of metal, and probably whatever other structural parts were needed beyond his ribs/synthetic spine. They're covered by what looks like real skin, considering all the blood. I think it's reasonable to assume that they took skin samples and grew duplicate swathes in the lab in the early stages of his treatment, so they wouldn't need to worry about rejection when they grafted it onto him. They probably made or simulated subcutaneous tissue also, so that his arm doesn't look (and feel!!) like skin stretched over a bunch of metal. I feel like probably, people would say something if Lasse threw an arm around his shoulders and ended up with a bruised forearm lmao

What I'm really wondering about is his organs. It's been way too long since I took a biomaterials class, and there would be enough innovation 300 years down the line that all the stuff we use now would be moot anyway, but I wonder how many of his organs were grown or transplanted, and how many were just substituted with mechanical systems that do the same thing.

This is a part I'm really no expert in, but I feel like just putting in filtering systems to replace his kidneys would probably be a lot easier than growing him new ones. They'd make him a functioning urinary system to connect the filters to, but tbh that whole system would probably be easier/simpler to just re-engineer.

I feel like his lung would need to be organic to deal with expansion and just. All that oxygen exchange? But it's entirely possible that a synthetic lung exists 300 years in the future that they could install. Pulmonology isn't my strong suit Px

Digestive system would need to be completely rebuilt, and I've always imagined it as synthetic, just his intestines replaced by a mess of tubing, possibly engineered to increase their overall surface area, reducing the length of intestine needed and leaving room for other systems around them. His esophagus would still be there, at least part of it, so they'd just integrate that into an artificial stomach

What's REALLY tripping me up is his circulatory system. Like, okay, he has a heart, and re-creating the major veins and arteries would be doable, but - interfacing them with the lung so the blood can pick up oxygen?? Interfacing them with the stomach and kidneys and liver properly?? Like, I do not know how you would functionally recreate a capillary bed and that sounds like a job for Future Bioengineers lmao. But I just.

You'd think at first that he wouldn't have as much blood because of all the mechanical systems, and I think he'd probably have less than average, but most of your viscera is involved with processing energy to keep your brain going, right? So your blood still needs to go down to your intestines to get those nutrients in order to bring back up. And, on top of that, his skin - which presumably covers the majority of his body, and definitely covers his limbs and upper chest - is vascularized and needs blood, too.

So, he still needs a decent chunk of blood for his body to run properly, which is great and A+, except for the fact that blood is made in your bone marrow, and guess what he doesn't have a whole lot of, anymore?

I don't know if they'd be able to like, create some kind of system that approximates bone marrow, or somehow supplement the stuff he has left in his left arm and remaining ribcage/breastbone/spine, but this would also significantly impact his immune system since bone marrow is also where your white blood cells come from. So like...that would be a serious issue they would need to address, maybe they'd somehow put bone marrow in his prosthetic long bones, with enough of the hormones/stuff that tells it to keep production of BM up, since it's constantly reproducing itself? Or else just have a whole extra box in his abdomen that's like "no, you make blood now" idk like I said, this is not My Thing

Again his immune system would be fucked, so the Bone Marrow Box would also need to replenish white blood cells, which would not at all help with replacing his lymphatic system. His thymus would probably have survived since it's over the heart, but his spleen is gone and - yeah, I'm not qualified to talk about this lmao

tbh I don't understand the liver or pancreas or gallbladder at all, and at this point I'm too afraid to ask

But! His nervous system! is something i am qualified to talk about, buckle up kids we're going for a ride

because his brain/brainstem/spine to T9 ish, probably, would have survived. Which means his use of his left arm would be 100% intact. Tbh after all this he's almost definitely left hand dominant, even once he gets a functioning right arm again, for reasons I will get into in probably a few paragraphs

For the mechanics of a prosthetic arm, tbh in the 24th century they've probably perfected it. We've come a long way now (well, as of 2018, when I wrote my thesis) in making a hand that can physically move in the ways a real one can. the real problem with fancy stuff like this is controlling it.

Lichty would functionally be a shoulder disarticulation amputee (where your ball and socket joint is disconnected), which is. about as high as you get. Your major nerves to the arm are the radial (back of your arm/hand), median (thumb half of your arm/hand), and ulnar (pinky half of your arm/hand). Those three kind of thread around your collarbone before dipping down into your arm, splitting up gradually into smaller nerves that innervate different parts of your arm and hand.

Sounds great and neat and simple, right? You just follow the nerves and make new wires and attach them to the prosthetic, right?

(((((((:

nerves are a FUCK, and yeah, none of that is how it works, and tbh I feel like evolution just made it overly complicated on purpose, just to frustrate people because oh my god

To slightly oversimplify, you have two different kinds of neurons making up your nerves: sensory and motor. Sensory takes inputs from the endpoints (your skin, typically) and sends them back up the spinal cord to your brain. Motor takes inputs from your brain and sends them down to the peripheral nerves to create a result (typically, muscle contractions). These are not sorted into neat sections within the larger nerves, and aren't especially easy to differentiate, especially if you're just trying to zap a whole nerve with electricity to make the muscle go. you're gonna hit all sorts of muscles, and all sorts of sensory inputs, and it's a mess.

Here's a basic diagram of a nerve for reference:

Basically, what you need to know is that every axon (neuron) is going to innervate a particular muscle fiber, or send a particular type of sensory input for a particular patch of skin. These axons are not sorted neatly by type of neuron or area of the arm/hand. They regularly jump between fascicles throughout the length of the nerve, and fascicles aren't neatly sorted, either. So, trying to target a particular fascicle, for example, is usually a lost cause. (without putting an electrode INTO the nerve, which is a Whole Other Thing that's being studied, but urgh)

Currently, myoelectric prostheses are the 'state of the art,' where there are sensors on the inside of the socket that read muscle activity in the residual limb and use it to power the prosthetic. This...wouldn't work for Lichty for a variety of reasons, and is generally not super well received by patients today, anyway. Typically, if you're lucky, you get 4 electrode sites, so for example, you would be able to flex/extend your elbow, and open/close your hand. Not exactly 27 degrees of freedom, yeah?

A process that tbh could work well in conjunction with future!prosthetic arms is something called targeted muscle reinnervation (TMR), where they basically say 'hey Lichty, try and flex your right elbow,' they record which nerve endings in his residual shoulder light up, and then they attach those to the mechanism that flexes his elbow. (Typically they deal with fascicles, if I remember right, but tbh in 300 years I wouldn't be surprised if they could go more specific.) It wasn't the focus of my research - our lab did hands primarily, and TMR is usually reserved for high level amputees, and it's a SUPER invasive surgery, so not a lot of people go for it. But lichty's just about as invasive as you can get lmao, so

TMR can also do some limited sensory feedback! basically, they stimulate different nerve endings and ask him what he feels and where. That's where a phantom limb map comes into play big time. Depending on how complete it is, he could say "yeah it's upper arm, vaguely pressure?" or "yeah it's the back of my upper arm but sort of to the side, and about halfway down, and it's sharp poking." Both the motor and sensory stuff are kind of hunt and peck searching but they kind of have all the time in the world to work with him on this, so I think it'd be a really good option for him!

So, google targeted muscle reinnervation if you wanna learn more! It's cool as fuck, and it's the thing that I think is probably most viable for Lichty to get use of his right arm back! I don't know that it'd give him full movement and full sensation, but it'd be enough to go on - especially since they'd definitely prioritize getting the most common sensations and motions working. A couple people in my lab were looking at combining different movements to reduce the number of movements you'd need for prosthetics in general - moving your wrist at a certain angle to approximate both radial deviation and wrist extension, for example.

Now legs, I am less qualified to talk about. TMR also works for them as far as I know, though balance and gait would be a Whole Thing, he'd have to relearn how to walk, not just because he's been bedbound for so long, but because he has to learn how his new legs operate, and where his new center of gravity is, and just...yeah.

I imagine probably, legs are the last thing they get him working on - they get his torso finished and operational and closed up, and at this point he wouldn't need to be quarantined/sterile anymore. If he really wanted to be up and about at this point, they could get him a power wheelchair, or a one-arm-propel manual chair would work too. Then they'd get him an arm and start him with therapy for that, and skin grafts. Once he's recovered from the arm surgeries and doing well enough they'd probably start talking about prosthetic legs.

Depending on how well TMR works 300 years from now, he'd have to re-learn grip strength, pressure, heat, like he'd have all new baselines for his new limbs which would in particular impact his hand. That'd be a looooot of PT and OT to make sure he doesn't drop or crush stuff on accident. He also may need to learn to operate without proprioception, depending on whether his phantom map included that. Proprioception is knowing where your limb is in space without looking at it - so like, if he didn't have it, he couldn't just like reach over and grab something, or type on a keyboard, without watching his hand as he did it - at least without a lot of practice and trial and error.

also your nervous system does sympathetic and parasympathetic stuff which is like, the automatic 'tells your organs to do their job' except i know next to nothing about that. so uhhhhh I think it'd be reasonable to assume that all the mechanical replacements for organs have their own like, 'battery' and 'brain' in them that keep them going properly and that's all i'm gonna say about that

holy jesus god this nervous system section is like as long as the rest of it combined i'm so sorry

His ribcage would need to be rebuilt in metal, which we can see in the pics. His spine would also need to be, if only to connect his ribs to his new pelvis lmao, but I guess it looks like they built in more metal around his abdomen too, so the spine would be slightly less structural than in the normal body. but - yeah, there would definitely be a lot of work going into into 'printing parts that will keep all these obscenely expensive organs in place and connected to the right things'

(oh that's another thing!! I headcanon that all these custom parts are 3d printed to his specs, in whatever material is best for that particular job. Presumably the material options are a lot more than we have now, and esp the metal structural parts, I think would make a lot of sense to print)

In terms of skin coverage!! Pictures are inconclusive whether he has skin covering his abdomen, or just his upper chest and limbs!! We can see skin on his hip and shoulder, but none in between, but I can't tell whether that's because his side was damaged worse, or if there's no skin there to begin with. Personally I think grafting skin to metal would create all sorts of New Issues that would be more effort than it's worth, but shrug, and also, leaving it open, with just a brace to go around his abdomen as extra support, would give him/his doctors easier access if anything were to go wrong. In my fics I go with the brace solution, because angst, but YMMV

skin coverage brings up all sorts of angst that his silly swimsuit just cracks the surface of. he's def wearing that suit for at the VERY least the skin graft scars, and also probably because he doesn't have skin on his abdomen sdlfkjsodfjsl

The other fun thing that would need to be taken into account for lichty! Is that! He's twelve (ish) when this happens! And twelve year olds! Aren't done growing! Lichty's pretty tall, 5'11" ish if I remember right, so it's not like they just stunted his growth permanently.

If he's 12 when he's injured, I'd guess he's probably 14 ish once he starts looking at getting prosthetic limbs. 14 yo boys aren't done growing either, so they'd either have to make him Weirdly Long for a teenager before he grows into his prosthetics, or make his limbs and torso designs growable to match what they think his height and weight would've been.

Growable limbs would be Really Difficult but probably doable? he'd just have to come in every several months after he's discharged to get Stretched (lol). On the other hand, he's probably actually pushing 17 by the time he's discharged, by which point most teenaged boys are done growing. So, it would make sense for them to make him Long while he's an inpatient, since that last year of therapy would be the most intense/functional, and also when he'd be roughly his adult size. So, he'd be a little disproportionate for a few years, but theyre years that he spends largely in a hospital bed anyway, so it wouldn't be that big of a Thing?

Then, they'd be able to discharge him when he's ready, without any plans to bring him back unless something goes wrong

They would've just estimated what his limb lengths would've been, with some growth room in the size of his chest and his right shoulder. His remaining chest would still be scrawny as a 14 year old, when his torso's closed up, but on the off chance he turned barrel chested by the time he hits 17 lol they'd need a plan for that. Luckily, adult!lichty is scrawny af, so there was probably minimal adjusting that needed to happen there.

The other other thing is, he hasn't gone through puberty yet! And while some of the puberty hormones would still kick in on time, ie the ones that come from his brain, he's also now missing all his reproductive organs. so, he'd need to get injections for the hormones he's missing, probably, because he looks and sounds like he did, indeed, go through puberty

(it's my headcanon that he's infertile even though he desperately loves kids. He and Chris adopt a small horde once they retire peacefully from the job they definitely didn't die doing)

This kid definitely has chronic pain - phantom pain and otherwise - especially when he's in gravity. he definitely has sensory and motor deficits that he gets really good at hiding. he definitely prefers to stay in space because it lessens the pain, and also because it means he doesn't have to walk around, which reduces pain even more. He's probably got a backup cane and/or wheelchair stashed in the back of his closet for bad days on the surface. he probably goes to see dr moreno more than anyone else, which causes lasse and feldt and chris to constantly ask if he's okay, as well as they can around the secrecy rules. he's definitely left handed, and sometimes his right hand is next to useless depending on the day, so he's gotten really good at typing one handed, and maybe even prefers the one handed keyboard he learned to QWERTY or standard DVORAK or whatever they use on the ptolemy lol

uhhh he weighs more than a normal person his size, most probably, because of the metal parts. the blood flow means his arm and legs would be warm, and the skin has nails and hair and wrinkles that make it a convincing enough arm, but if you hold it too tightly or look at it too closely it looks a little off in a way you can't place

he's definitely got a Thing about people touching his abdomen or chest, not even like because he's touch-sensitive like setsuna, just because his stomach isn't gonna squish like everyone else's and that'd lead to way more questions than he's willing or able to answer

an artistic rendition:

lasse: when the FUCK did you get abs like this oh my god???

lichty: nervous sweating

but yea tldr is 'this kid definitely shouldn't be alive, but he is, so laura got to geek out about biotech and uh also his rehab would have taken literal years after the literal years of surgery to put him back together.' in other words he was probably recruited to CB like. Barely a few months after he left the hospital for good

((also, as an aside, i would like to make you all very sad and remind you that lichty's backstory is actually really similar to lockon's, he lost his family in a terrorist bombing as a kid, and was horrifically injured by it to boot. but so far as we can tell, he basically took the exact opposite approach to neil. like yeah, his cheeriness is probably a front at least part of the time, but like, he didn't go off the deep end, and join CB for revenge. he joined to make the world a better place, and never once talked to anyone at all about the stuff he went through as a kid, and never - so far as we can tell - blamed anyone for it))

((like idk guys just. lichty going through the same thing, only worse as lockon, and coming out the other end as an objectively happier and arguably better person, gives me a lot of emotions that i'm struggling to articulate sldkfjaosdjflad))

((also I definitely headcanon that the kpsa did the bombing that killed lichty's family too just because it hurts a lot, especially since lichty's bomb would've been roughly a year after Neil's))

I uh don't really have a conclusion here so. Have 4k words of science dump, thank u all for encouraging me yesterday to write it!!!

#gundam 00 #lichty tsery #lichtendahl tsery #fuck i love this kid so much i would die for him tbh #g00 #reference #mine #image ids in alt text #I am so sorry for the excessive run on sentences I tried #When I get like this I get very stream of consciousness #And editing can only do so much without having to rewrite the whole thing 😭

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