When a person loses a limb, his most important dream is to feel his arm or leg again. And not just to feel, but to perform with the limb all the movements available before injury or illness: take a cup, lace up shoes, walk with support on both legs. A bionic prosthesis, or a complex device that captures nerve impulses, allows you to return lost opportunities.
How did smart prosthetics come about?
The prototype of "live" prostheses was invented and described by science fiction writers. It was in their works that the arms, legs, eyes and hearts lost in battles were replaced by mechanical assistants that work better than living organs. The most famous example is Cameron's Terminator, who took only the appearance of a person.
Few people know that the prototype of modern prostheses dates back to the 19th century, when a metal ball was inserted into a wooden leg to make the lower part movable. But in the 20th century, these primitive devices were replaced by a bionic prosthesis created at the intersection of several sciences: medicine, engineering, bionics and electronics.
Scientists from different countries dispute the primacy in this matter, but the facts are that the firstA functional bionic arm prosthesis was presented at an orthopedic exhibition in the German city of Leipzig in 2010. In the years that have passed since this event, a huge number of prosthetic hands, arms, feet, legs and even dog paws have been developed in the world.
What is bionics?
This is a whole science that studies wildlife and the possibility of transferring the principles of the work of living beings into industrial counterparts. Engineers peep ideas from nature and embody them in their devices and structures. In this sense, bionic prostheses are just a drop in the ocean. So, Velcro fasteners known to everyone just copy the way burdock seeds move. Suckers are borrowed from leeches. When designing submarines, they took an earthworm as a model - all of its “compartments” are autonomous. The incredibly hardy metal openwork of the Ostankino and Eiffel towers is a multiply enlarged copy of a human tubular bone. The weave of metal that so admires everyone is a copy of the structure of bone tissue, combining strength and flexibility.
Even a high-rise building in which such different families live at the same time is written off from a honeycomb. The idea of life of different people in "cells" under one roof with common communications copies the way of life of a bee colony.
Bionic incarnations are found in many objects around us: car tires, airplanes, surveillance cameras, boats and the most common articulations.
How does a simple bionic prosthesis work?
After an injury or during an illness, a limb is amputated. The remaining stump consists of manytissues: skin, muscles, bones, blood vessels and nerves. During the operation, the surgeon brings the remaining motor nerve to the remaining large muscle. After the surgical wound has healed, the nerve can transmit a motor signal. This signal is received by a sensor mounted on the prosthesis. A complex computer program is involved in the process of perceiving a nerve impulse.
Therefore, the bionic prosthesis can perform only those actions that are prescribed in this program: take a spoon, fork or ball, press a key, and the like. Compared with the absence of a limb, the possibility of even a limited number of motion is a huge improvement. However, even the best and most advanced bionic prostheses cannot yet perform all those small and precise movements that a living limb is capable of.
How does a nerve impulse travel from the brain to the prosthesis?
To understand how bionic prostheses work, you need to remember normal human physiology.
Movements that we make repeatedly during the day are called automatic. Getting up, going to the toilet, washing, brushing teeth, getting dressed - all this does not cause any thoughts in us. The body does everything it needs as if by itself. But in fact, the beginning of any movement is a thought. That is, at first we think: we need to brush our teeth, make coffee, get dressed. The brain sends signals to the muscles that are involved in this movement. A muscle can contract or relax only on a signal from the brain. But the process takes place so quickly and smoothly that we do not have time to realize what is happening. ATIn the case of a prosthesis, everything is more complicated: at first, the motion signal is read by an electrode located next to the nerve brought to the muscle, and then sent to the processor inside the prosthesis. This process is also quite fast, but the speed of performing actions is still inferior to a living limb.
Artificial human "parts"
Since the first bionic prosthesis was introduced, science has come a long way. If the first models were bulky, required switches and could perform only the simplest movements, then modern models can hardly be called prostheses. These are elegant pieces of engineering that look like they've stepped out of a futuristic movie screen.
The prosthesis is absolutely similar to a he althy hand, it can write, hold cutlery, a car steering wheel or a chicken egg. For the perfection of movements, a person's own tissues are sometimes used from other parts of the body - from the legs, for example.
Ideas from the future
Engineers and scientists are unstoppable in their fantasies. So, scientists were even able to “bypass” the damaged retina, broadcasting the image of the environment directly to the optic nerve. A person who is blind due to an injury, with the preservation of the optic nerve, can count on seeing familiar faces again or a beautiful sunrise.
There are already devices that improve brain function. For example, tremor paralysis or Parkinson's disease can be treated with an implanted electrode.
To people who have become immobile due toparalysis implant electrodes directly into the brain so that they can control artificial arms and legs. For a person who is completely dependent on others, the possibility of self-service is an indescribable joy.
The issue of chips implanted under the skin that can replace keys, a bank card and an identity card at the same time is being discussed.
What do we have?
The most famous enterprise producing bionic prostheses in Russia is the Moscow Prosthetic and Rehabilitation Center. Here, prostheses are assembled from modules, products from Germany, Iceland and Russia are used.
The prosthesis of each person has individual characteristics. This is the level of amputation, and weight, and height, and occupation, features of gait and small movements, age. Many self-learning modules are used. Not only a person adapts to a prosthesis, but also a prosthesis to a person. The self-learning module, equipped with built-in artificial intelligence, remembers the features of the gait and the route of movement. The module "learns" not only the width of the step and the load on the limb, but also remembers the number and height of steps, potholes and pits on the way. The modules replicate the actions of the brain preparing a step or other movement.
How much does a "live" prosthesis cost?
The cost of bionic prosthetics is still high and can reach millions of rubles in complex cases. However, the return to a full life is difficult to evaluate in material terms. In fact, the installation of bionic prostheses is the only way for a disabled person to return to normallife: build and implement plans, support a family, achieve career heights.
The most important thing is to return to the community of he althy, self-reliant people. People with "live" prostheses continue to lead a normal life, dance and even receive sports awards. That is, the prosthesis becomes so much a part of the person that it is difficult to distinguish the actions of living muscles from their bionic counterparts.
Prosthetics: stages of development
Compared to conventional bionic prosthetic hand - a real breakthrough. More recently, a person who lost a hand could count on only two possibilities: a skin flap was formed between the ulna and the radius so that a person could grab large objects, or a hook was attached to the stump. Both were uncomfortable and unaesthetic. Today, even the formation of a stump for a future prosthesis begins in the operating room. From the first days of the postoperative period, a prosthetist works with the victim, helping to choose the best combination of parts. The stump is formed and trained, and the parts of the future prosthesis are maximally adapted to the remaining possibilities. A delicate silicone cuff with embedded chips comes into contact with the skin. There are no abrasions from modern prostheses. The program for each product is developed individually, depending on what the person is doing. The task is to restore the function as much as possible.
Helping the Disabled
A person who has lost a limb must undergo a medical and social examination. Simultaneously with the establishment of the groupdisability, a program of social rehabilitation is being developed for everyone. Rehabilitation involves the use, first of all, of technical means that contribute to the return of a person to work. All bionic limb prostheses are included in the mandatory list of such technical means. A person has a choice: within the framework of the rehabilitation program, receive a finished product or purchase it on their own with subsequent receipt of monetary compensation. The amount of compensation is calculated based on the average cost of similar prosthetic products.
What are the developers working on?
Modern bionic prosthetic hands perfectly perform subtle movements, but a person does not get the sensations from them that he is used to. So, a prosthesis can stroke a person's hair, but you can not feel the warmth of the scalp and the softness of the hair. Scientists are now working on eliminating this shortcoming. Specialists have already learned how to splice bones with titanium, and connect sensors of movements and feelings directly to a living nerve. Thus, a bionic hand completely replaces a living one, and a person receives tactile sensations, which he has been deprived of for many years. The direct connection of nerves and muscles with a technical device greatly increases the speed of movement, bringing it closer to the natural.
What parts does a bionic leg consist of?
Modern bionic leg prosthesis includes several mandatory elements, such as:
- silicone cuff with built-in sensors;
- support - a titanium rod, shaped likedrumstick;
- articulated module with micro-engines and processor;
- artificial intelligence unit that processes all incoming signals.
The latest models of prostheses from leading German companies have a special coating that is very similar to skin. Synthetic skin has a dual purpose: it protects the details of the prosthesis from moisture and performs a cosmetic function. You can leave your coated prosthesis on, shower with it, and walk through puddles.
A little fantasy
Today, several people live on the same planet with us, having 2 and even 3 bionic prostheses at the same time. Invented synthetic leather that changes stiffness. Exoskeletons have been invented to help paralyzed people walk. Developed products controlled by the power of thought. Experiments are underway to grow nerves in microchannels. Theoretically, the day when it will be possible to grow a nerve of the required length is not far off. Scientists are trying to blur the line between wildlife and a technical device. The number of movements performed by bionic prostheses is constantly increasing, and so is their complexity.
All this gives great hope that a person will become stronger than the disease.
Prosthetic limbs are becoming a routine procedure that returns a person back to normal. Perhaps the day will come when any part of the human body can be replaced with an artificial one. At least I really want to believe it.
