Prosthetic Limbs in Violet Evergarden
First off, I want to say that Violet Evergarden does live up to the hype and is an excellent show. I saw the English dub on Netflix and loved it. The animation is some of the best I have seen in a long time and it is a joy to watch from a visual perspective. I feel like the English voice cast really nailed the characters, and I have no problems with the dub. As to the story itself, I do not want to say much other than it is something of a coming of age/discovering your emotions type of story. But you didn’t come here for a review of the anime, you came here for the science, so what is the science in Violet Evergarden;
Warning: minor spoilers ahead.
There are many elements of Violet Evergarden that could be examined, from PTSD, the struggles of rehabilitating child soldiers, to dealing with the grief from losing a loved one. While all of these are worthy of examination, I’m not a psychologist and I will be looking in a different direction, specifically Violet’s prosthetic arms.
The female lead, Violet Evergarden, loses both of her arms during what I can only assume is this universe’s version of World War I, and has them replaced with highly advanced prosthetics that give her fully functioning arms and hands. (I’m still not sure how she didn’t die of blood loss from having both her arms shot off.) This is something of an anachronism as such highly advanced prosthetics did not exist in the real world yet, let alone could have been attached during World War I. Additionally, no explanation is given for the origin of her arms, and the characters treat her arms as unique, but not completely out of the ordinary. If you already haven’t figured it out, I am going to call Violet Evergarden’s arms busted, but this does give me the opportunity to talk about the history behind prosthetic limbs and look at where the real world prosthetic limbs are headed in the future.
First Prosthetic Limbs
I imagine most of you when you think of the earliest prosthetic limbs are probably picturing a peg legged pirate from the golden age of piracy (1650-1730). However, that is not actually the case, and while not common, prosthetics are far older. Currently the oldest known prosthetic is from a female Egyptian mummy dated between 950-710BC. The prosthetic in question was for a missing big toe and its design indicates that it was made for everyday use and was not a ceremonial part added for burial.
The next prosthetic limb is a bronze and wooden leg from the Romans circa 300BC, called the Capua leg.
I couldn’t find out much about the leg, as it was destroyed during an air raid on London during WW2, but replicas were made before that happened. To my untrained eye it appears to be an above the knee prosthetic. This is due to the size of the upper half of the prosthetic and the way it narrows towards what could be considered a knee and expands back out for a calf.
Despite the promising start during antiquity, prosthetic limbs do not appear to make much progress, despite how ornate they might look.
The hinges and articulation might imply a high degree of functionality, but sadly that is not the case. The hinges allow the limb to be set in a variety of positions and allow the person to hold things, but it cannot be moved on the fly. In reality many of these limbs were designed to hide the fact that the individual was missing a limb instead of giving the wearer any degree of functionality.
The Renaissance brought significant advancements in prosthetic limbs and some of those enhancements are still used today. Some consider Ambroise Paré to be the father of modern prosthetics since he made several contributions that are still in use today. His above the knee prosthetic included knee locking devices that make standing and walking easier, and a harness system, both of which are still in use today. Lorrain expanded on these enhancements by making artificial limbs out of lighter materials like leather, paper and glue instead of metals like iron. The lighter prosthetics were closer to the weight of the original limb, and reduced the strain placed on the patient. (The weight of the prosthetic affecting the body is something that is mentioned in Full Metal Alchemist in regards to Edward Elric.) This of course begs the question of how Violet was able to move the way that she does with two above the arm prosthetics that are made out of metal, and durable enough to block gunfire. The first aluminum prosthetics appear after WW1 and if we assume that the war in Violet Evergarden is similar to WW1, then it is possible for her arms to be made of aluminum. The average density of human tissue is 985 kg/m3, while the density of aluminum is 2,700 kg/m3. This means her replacement arms could weigh almost three times the weight of her original arms. That should have impacted her ability to move.
Prosthetic limbs continued to make small advancements in function and how they were attached to the patient’s body. The carnage of the American Civil War led to a large increase in amputees, which in turn led to an increased interest in artificial limbs. James Edward Hanger was a Confederate soldier and engineering student who lost his leg early in the war. After returning home, he designed and built the “Hanger Limb.” He then went on to found the Hanger Company, which is a billion-dollar prosthetic limb company today.
It was also during this time period that we begin to see truly controllable prosthetic limbs. This was first done in 1812, by using straps connected to the opposite shoulder to control an artificial arm. This was a major advancement and does a lot to restore a limb’s functionality and this was the method used to control limbs until after WW2.
This brings us back to Violet, and while she initially struggled to use her replacement limbs, she quickly learned how to type and use her replacement arms just like she would her original limbs. There is just no way that level of precision and control of an artificial limb is possible using just the small muscle movements of the shoulders with the prosthetic technology of WW1.
Necessity is the mother of invention and sadly the necessity that drove major advancements in prosthetic technology in the 20th century was two world wars. The US federal government founded the Artificial Limb Program to help deal with the large number of limb amputees caused by warfare. One such example of the advancements made during this time was that of Ysidro M. Martinez, who made a new type of limb in 1970 which took a slightly different approach to artificial limbs. Instead of focusing on giving a leg amputee a normal looking leg and gait, he focused on making the walking easier for the patient.
An extreme example of this would be the now disgraced Olympian Oscar Pistorius. His leg prosthetics look nothing like normal legs, but they allow him to run like an individual with completely normal legs.
In fact, it actually brings up a second point which science fiction loves to bring up, the idea of super powered artificial limbs. While his unique blade like legs are not super powered they are actually slightly more efficient than human legs in rebounding off the ground. This led to some questioning whether or not he had an unfair advantage, but these questions did not stop him from participating in the Olympics.
Violet’s limbs do not show any instances of enhanced strength beyond being bullet proof. Just in case you are wondering about that scene at the end of the series, the strength needed in that scene would come from the legs and back, not the arm.
Modern Prosthetic Limbs
1-The socket is where the limb attaches to the body. In modern prosthetics the socket is made out of things like silicon and other material that can give a firm soft fit to the body. This is actually carefully fitted and unique for each patient as everyone’s body is slightly different. In some cases, the limb can be attached to the patient’s skeletal system in a process called Osseointegration. Titanium is one of the preferred metals for this process due to its ability to integrate with bone.
If I had to guess, I would say that Violet’s arms are connected in this manner, due to how she didn’t rip her arms off her body during the climactic scene at the bridge.
2- The pylon is the part of the artificial limb that provides the structural support. They are typically made out of aluminum, carbon fiber, and plastics to remain lightweight and strong. The pylon can be covered by other materials and shaped to make it appear more like a normal limb. The limb below is covered by a plastic mesh so it looks normal when wearing clothing.
3- The suspension works with the socket to provide a secure comfortable fit to the patient’s body.
There are a number of ways that modern artificial limbs are controlled including myoelectric, computer chips, or neural interfaces.
Myoelectric control is a more advanced version of the old method of using straps attached to still functioning parts of the body. In myoelectric control small sensors are attached to the muscles on the remaining part of the limb. When you slightly move one of the muscles the artificial limb reacts in a preset controlled way. This would allow a patient to grip things with an artificial hand or rotate an artificial wrist. This works great for an artificial arm, but it is more difficult for a leg replacement, especially prosthetics that include a replacement knee. This is due to the constantly changing conditions that occur while walking. This is where microprocessors come in by helping to regulate the artificial leg, improving function.
The neural interface is the most advanced and cutting-edge version of prosthetic control. It is accomplished using targeted muscle reinnervation or TMR for short. This might sound very complex, but it is actually simple in concept. When you lose a limb, everything in your body works up until the point where the limb was lost. This includes the nerves which control the muscles.
Imagine cutting the electrical wire leading to a lamp. The lamp will no longer work because the wire is cut, but the wire leading to the lamp will still carry electricity, which can’t reach the lamp because of the break.
What TMR does is try to connect the nerves that would have gone to the missing limb to the prosthetic. The trick of course is connecting the right nerves to the prosthetic, and then training the brain to use the prosthetic like a normal limb.
This is currently very cutting-edge technology and not something that is possible in a post WW1 setting. Now one area where I will have to give Violet Evergarden credit is the adjustment period where Violet struggles with her new arms, specifically her hands.
I hope that you enjoyed learning a little about the history of prosthetic limbs and how it applies to Violet Evergarden. Just in case you are wondering, you could replace Violet Evergarden with Edward Elric from Full Metal Alchemist and the result would be the same. If you have any questions or comments please leave them in the comments below.