Prosthetic limbs to the Rescue.

On a sunny Afternoon, George came home from work early and was excited to see his 4-year-old son Frank riding his bicycle in the driveway. He smiled and kissed his son, then he decided to mow the lawn in his compound.

While he was mowing the lawn with his lawn mower he got to a dead end at the side of his house and as he tried to reverse the mower to turn around. He had no idea that frank had left his bicycle and followed him. Alas! He felt a bump

George had accidentally run over his son’s leg. He looked down at his son in shock and immediately lifted the mower off Frank but it was too late. Frank kept screaming in pain but his father was even screaming louder. Well Frank was hospitalized for 28days and the rest they say his history.

A few days back I was surfing the internet Guess who I saw? I saw a very energetic and vibrant Frank with a prosthetic limb running and playing around with other kids.

Frank’s case is just one of the millions of accidents that happen annually across the globe. if you have ever played a sport and you fractured some bones in your legs and could not walk or run for a few days. It’s at those points you would realize that walking and running are delicate and complex tasks that our body performs effortlessly.

Just take a look at your hands for a few seconds, this hands perform a whole lot of function like writing calligraphy, playing of instruments, holding items, touching, working out amongst other things.

Have you ever taken the time out to just appreciate this superb and fascinating piece of biology called your body or you just wake up and take it for granted? We perform a lot of these daily activities so routinely that we begin to take them for Granted.

Like a popular quote we hear often: “we Don’t Appreciate what we have until it is Gone”

But what happens when an individual loses a limb due to an accident, injury or disease and they can no longer execute movements with their limbs. This loss could either be an upper extremity amputation which involves the total or partial loss of the arm or it could be a lower amputee which could be the loss of one or both legs. Either ways the person wouldn’t be the same again.

Gone are the days when a person loses any part of their limbs, they just stay helpless and life becomes useless and unbearable, so they just wait for death. But with the advancement of technology this individual still have hope and can still live an amazing life using what is called prosthetic limbs.

Today I would be explaining how this prosthetic limbs work.

Prosthetic limbs were created to assist individuals that had lost their limbs to bring back some of the capabilities lost. Prosthetic limbs cannot be compared to a biological limb but then they perform a huge role as they can significantly restore some major capabilities lost to these individuals.

Prosthetic limbs have advanced in recent times from heavy and limited capabilities, now prosthetics are lighter and can perform a lot more functions because they are now more realistic due to the use of more suitable materials for manufacturing them, carbon-fiber composites and advanced plastics which would make them stronger and lighter at the same time. Another major aspect that contributed to the rapid improvement in the prosthetic industry that makes prosthetic limbs more controllable and have swift Adaptability when performing tasks is electronic technologies.

Most times Prosthetic limbs are quite unique to the individuals affected and the type required is strictly based on the level of amputation. Taking a look at the prosthetic limb required for an amputation above an individual’s knee definitely needs a prosthetic with an artificial knee but that is not the case of an individual with amputation below the knee the individual can still make use of his/her knee. Regardless of the kind of prosthetic limb fabricated, they all still have some basic and similar parts in common.

For a prosthetic limb to perform optimally a structural support is required that would perform the role of the skeleton in the prosthetic limb. This internal frame is called pylon and lately its formed by using lighter carbon fiber composites. To make these limbs unique to individuals these pylons are enclosed in a cover which is shaped and sometimes colored to look identical with their skin color. In fact, some of this limbs look so real that if you don’t properly pay attention you might mistake them for real limbs.

For this prosthetic limbs to get attached to an individual residual limb there is a part of the prosthetic limb known as the socket that makes contact with the individual. These socket are very delicate and if they are not properly placed to fit into the residual limb they can do more harm than good by causing more pain to the individual so this socket must properly fit. To ensure they are quite comfortable and they fit perfectly the inner part of the socket contains a soft liner and the individual would wear layers of prosthetic sock to achieve this.

You might wonder how the prosthetic limb stays attached to the individual’s body. This is where the role of suspension system comes to play, this is the part that keeps the prosthetic limbs attached to the body. This suspension differs depending on the type and use of a prosthetic limb, some stay attached by fitting directly around the shape of the limbs, some make use of straps, belts or even sleeves to keep them attached or suction which involves the prosthetic limb fitting tightly to the residual limb while an airtight seal is used to keep it attached.

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Let’s take a look at how they are made

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Designing and fabrication of a prosthetic limb is a very Delicate process that requires precision because it is mostly customized for each patient. For this to occur the specialist in charge of fabricating and fitting of prosthetic limbs known as the prosthetist, accomplishes this herculean tasks of interfacing the human body with artificial devices requires patience and all round skill in anatomy, engineering and physiology.

Before designing the prosthetic limbs, it is imperative that proper measurements are taken and in most cases this specialist begin to take these detailed measurements before the individual’s limb is amputated during surgery so as to get the correct measurement and get details required by the doctors and prosthetists to carry out the successful actions.

Then the amputation surgery can take place and as soon as the wound has healed and the swelling reduced after several weeks, a plaster mold of the residual limb is taken to be used as a sort of template to make a duplicate of the actual residual limb. When this has been achieved a duplicate of the individual’s residual limb is created, then they can perform continuous tests on the prosthetic limb as it is being built using this duplicate. Nowadays computerized digital measurements are taken to facilitate this process.

Amongst other factors considered during this process are the individual’s health, structure of the residual limb, the state the skin is in, location of certain parts of the limb such as the bones, muscles and tendons. And Once the prosthetics is ready physical therapy commences.

Physical Therapy is inevitable and of utmost importance when an amputation surgery takes place and prosthetic limb fitting occurs. It takes Several weeks and months to train and rehabilitate individuals using prosthetic limbs because it’s actually not an easy activity to learn. During therapy the specialist monitor the patient and makes necessary adjustments if the need arises. Majorly the point where the prosthetic socket and the individual’s residual limb meet is where the specialists focuses on more due to the shrinking of muscles over a period of several months.

The changing size can be tackled by changing the socket of the prosthetic limb to adequately cater for the shrinking or the sock-like dressing of the residual limbs are varied to take care of the shrink. After this therapy the injured individual would continuously have to see the prosthetist all through their life for regular checkup and upgrade.

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Let’s take a look at How this individuals control this devices?

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Prosthetic limbs come with different functions and specifications which are determined by the needs of the individuals affected. Some prosthetic limbs are manufactured mainly for appearance and there is little concern for controllability. This type of prosthetic limbs is called cosmesis and they can be so advanced that they can look exactly like a real limb. These cosmesis are created to match the individual’s skin tone using advanced plastics and pigment. The can be designed to look exactly like the missing arm with fingerprint, hairs and freckles indistinguishable.

Some other prosthetic limbs have usability and function as their main role, these are called functional prosthetic limbs Generally for a prosthetic hand to perform a task like gripping an item it makes use of a pincer like split hook which can be opened/closed. For This type of very delicate prosthetic limb to fit in and look like a real hand they are covered with a glove like covering.

Several ways are being used by the individuals to control this functional prosthetic limbs:

In some cases, cables are connected from the prosthetic limbs to somewhere on the body, this cables acts as control. This is called Body powered prosthetic limbs. In the case of an individual that makes use of a prosthetic arm, for controllability a cable is passed from the prosthetic limb and attached with either a strap or harness to the opposite healthy shoulder such that the healthy shoulder can be moved in suitable ways to move the prosthetic limb.

With the advancement in technology there are some limbs that can be powered with motors and controlled by the individual in several ways. This type of prosthetic limbs is called Externally powered prosthetic limbs. The individual controls the prosthetic limb by toggling switches or sometimes buttons using the opposite shoulder or the remaining muscles in the residual limb to make movements. To perform different motions using the prosthetic limb, different sequence of switch toggling is required in this type of prosthetic limb.

When muscles contract they generate small electrical signals, so electrodes can measure the muscle’s movements if they are placed on the surface of the skin. These contractions are used to control the prosthetic limbs. This is a more advanced method called myoelectric which involves listening to the remaining muscles in the residual limb that can still be contracted by the individual and no physical button is pressed to move the prosthetic limb.

Microprocessors and sensors are used in advanced artificial legs to adapt and take critical measurements while the individuals walk. These microprocessors learn how the individual walks over a period of time and adjusts the stiffness of the knee to match the walking style.

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CONCLUSION

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Prosthetic limbs have made a tremendous impact in helping people live amazing lives after losing their limbs tragically to accidents or diseases. Unfortunately, the cost of purchasing a prosthetic limb is very high due to the electronic component they are built with, so it’s not surprising that they are not so common in developing countries. In the nearest future I am certain that individuals would be able to feel their prosthetic limbs and have their senses restored.

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REFERENCES

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Prosthetic Limbs

The Science Behind How Prosthetic Limbs work

Prosthetic Limbs Technological Advancement for Amputees

Making Prosthetics Feel more Natural

Prosthesis