What is a prosthesis?
A prosthesis is any artificial device that replaces a missing body limb following an amputation or due to a condition present at birth. There are many different types. They are usually named after the part of the body that has been replaced:
- Transtibial or “below the knee”: replaces the lower leg.
- Transfemoral or “above the knee” – replaces both the lower and upper legs.
- Transfarial or “below the elbow” – replaces the forearm.
- Transhumeral or “above the elbow” – replaces both the lower and upper arms.
Prosthetic hands and feet are the least common types of prostheses.
Prosthetic arms and legs are usually made of a strong but lightweight material, such as carbon fiber. They are customized for the patient, as it is important that the socket (the part that attaches to the body) fits precisely to avoid skin or tissue damage.
Hip prostheses
Some are operated by a control system. These can be:
- Mechanical systems: these are often found in prosthetic hands, where cables are attached to the opposite shoulder. When pulled, the artificial hand closes.
- Myoelectric systems: this is a much more modern system, where muscle impulses in the body are detected and amplified to feed the electric motors in the artificial limb that operates its movements.
What does the implantation of a prosthesis consist of?
The implantation of a prosthesis is a complex process that is part of a broader rehabilitation program carried out after an amputation.
The process begins a few weeks after the amputation is performed, once the amputated socket has settled. By measuring the healthy opposite limb, a mold is made that will form the base of the prosthesis. At this stage, you will likely be fitted with a temporary prosthesis to help you get used to wearing it, and while a permanent prosthesis is being constructed.
In preparation for the prosthesis, you will be taught a set of exercises to strengthen the remaining limb of the same limb, and the skin may need to become less sensitive.
You will usually have a say in the type of prosthesis you want to have. Normally, prostheses can be performed for functional or cosmetic use, but very rarely are they performed at the same time for both options. Even among functional prostheses there is a wide variety to choose from, as each model excels at a different type of task. The right model for you depends on the amount of physical activity you do and the type of activities that are important to you.
An artificial prosthesis typically lasts about three years for an adult and six months for a child; as a result, it is usually necessary to fit a new one since your body changes shape all the time.
Alternative treatments
Not everyone is physically prepared to face the extensive rehabilitation, physiotherapy involved in fitting or getting used to wearing a prosthesis. Instead, it is advisable to opt for a prosthesis for purely cosmetic reasons, as they look more like a real limb but do not provide any functionality (e.g. walking assistance). In other cases, the use of mobility devices such as a wheelchair may become more helpful.