Chapter 3: Prosthesis

A prosthesis is a kind of medical device (plural: prostheses; from Ancient Greek prosthesis, "addition, application, attachment")

It is important that the aesthetic and the functional requirements of the individual be taken into consideration while designing and putting together their prosthesis. For instance, a person may need a transradial prosthesis, but the individual will need to decide if they want an activity-specific device, an aesthetic functional device, a myoelectric device, or a body-powered device. It's possible that the individual's long-term objectives and current financial situation will guide their decision between one or more of these devices.

Craniofacial prosthesis may be broken down into two categories: intra-oral and extra-oral. A further subcategorization of extra-oral prosthesis includes hemifacial, auricular (ear), nasal, orbital, and ocular prostheses. Dentures, obturators, and dental implants are all examples of dental prostheses that fall under the category of intra-oral prosthesis.

Replacements for the upper esophagus, the trachea, and the larynx are some of the prostheses that may be found in the neck, Somatoprostheses of the torso include breast prostheses, which may be single or bilateral, whole breast devices, or nipple prostheses. Breast prostheses can also be bilateral.

Penile prostheses are used to treat erectile dysfunction, correct penile deformity, perform phalloplasty and metoidioplasty procedures in biological men, and to build a new penis in female-to-male gender reassignment surgeries. In addition, penile prostheses are used to build a new penis in patients undergoing female-to-male gender reassignment surgeries.

Prostheses of the upper and lower extremities are also included in the category of limb prostheses.

There are many different degrees of amputation that need upper-extremity prostheses, including the forequarter, shoulder disarticulation, transhumeral prosthesis, elbow disarticulation, transradial prosthesis, wrist disarticulation, complete hand, partial hand, finger, and half finger. An artificial limb known as a transradial prosthesis is one that may be used to replace a natural arm below the elbow.

There are three basic categories that may be used to classify upper limb prostheses: passive devices, body-powered devices, and externally powered (myoelectric) devices. Passive devices are those that do not need any additional power source. There are two types of passive devices: passive hands, which are mostly used for aesthetic reasons, and passive tools, which are principally utilized for a variety of tasks (e.g. leisure or vocational). A literature study that was conducted by Maat and colleagues has a comprehensive overview as well as a categorization of passive devices. The operation of body-powered or cable-operated limbs involves wrapping a harness and cable across the shoulder of the healthy arm opposite the one that is injured. Myoelectric arms make up the third group of prosthetic devices that are now accessible. These are able to function by detecting, via the use of electrodes, when the muscles in the upper arm move, which then causes a prosthetic hand to open or shut. When discussing prosthetic arms in the field of prosthetics, a trans-radial prosthetic arm is often referred to as a "BE" prosthesis, which stands for "below elbow prosthesis.".

Prostheses for the lower extremities may give replacements for limbs amputated at a variety of levels. These include disarticulation of the hip, implantation of a transfemoral prosthesis, disarticulation of the knee, implantation of a transtibial prosthesis, Syme's amputation, and amputation of the foot, a portion of the foot, or the toe. The terms "trans-tibial" and "trans-femoral" refer to the two primary subcategories of lower extremity prosthetic devices, respectively. A trans-tibial prosthetic device is designed for individuals with a trans-tibial amputation or a congenital defect that results in a tibial deficit (any amputation transecting the femur bone or a congenital anomaly resulting in a femoral deficiency).

An artificial limb known as a transfemoral prosthesis may be used to replace a leg that is amputated above the knee. Amputees who lost a limb below the femoral region may have a very difficult time recovering normal mobility. In general, a person with a transfemoral amputation has to expend around 80 percent more energy to walk than a person who has both of their legs intact. This is because of the complicated kind of movement that is involved with the knee. Hydraulics, carbon fiber, mechanical linkages, motors, computer microprocessors, and unique combinations of these technologies are being used in newer and more advanced designs to provide the user greater control. These technologies are also being combined in novel ways. A trans-femoral prosthetic leg is typically referred to as a "AK" or above the knee prosthesis in the prosthetics business. This is because the prosthetic leg is placed above the knee.

An artificial limb known as a transtibial prosthesis may be used to replace a leg that is amputated below the knee. Transtibial amputees often have an easier time returning to normal mobility than transfemoral amputees do, in large part because transtibial amputees keep their knees, which makes it possible for them to move more freely than transfemoral amputees do. Artificial limbs that are situated at the hip level or below are referred to as lower extremity prostheses. A trans-tibial prosthetic limb is often referred to as a "BK" prosthesis, which stands for "below the knee prosthesis," in the prosthetics business.

A person who has been fitted with a leg prosthesis may learn how to walk with the assistance of a physical therapist. In order to accomplish this goal, the physical therapist may offer verbal instructions and may also assist in guiding the individual via the use of touch or other types of tactile signals. This may be carried out either at a medical facility or at home. There is some evidence from previous studies that suggests doing this kind of exercise at home on a treadmill may increase the likelihood of the therapy being effective. The individual receiving physical therapy may experience many of the difficulties associated with walking with a prosthesis by using a treadmill, in addition to the treatment they are receiving.

The lack of sufficient blood circulation is the cause of seventy-five percent of lower limb amputations done in the United Kingdom (dysvascularity).

Prostheses for the lower extremities are often classified according to the amount of amputation or by the name of a particular surgeon:

Transfemoral (Above-knee)

Transtibial (Below-knee)

Ankle disarticulation (e.g.: Syme amputation)

Knee disarticulation

Hemi-pelvictomy (Hip disarticulation)

Pirogoff, Talo-Navicular and Calcaneo-cuboid (Chopart) amputations, Tarso-metatarsal (Lisfranc) amputations, Trans-metatarsal, Metatarsal-phalangeal, Ray amputations, and toe amputations are all examples of partial foot amputations.

Van Nes rotationplasty

Lightweight construction is used wherever possible in prosthetics, since this provides the amputee with more ease. A few examples of these materials are as follows::

Plastics:

Polyethylene

Polypropylene

Acrylics

Polyurethane

Wood (early prosthetics)

Rubber (early prosthetics)

Lightweight metals:

Titanium

Aluminum

Composites:

Polymers with carbon fiber reinforcements

Around the year 3000 BCE, prosthetics were first developed in the ancient Near East, with ancient Egypt and Iran providing some of the first evidence of prostheses,.

The Egyptian myth of the Eye of Horus, which goes back to around 3000 B.C., is where eye prostheses are first mentioned in written history, It entails Thoth plucking out the left eye of Horus and then restoring it to its original position.

Circa 3000-2800 BC, Iran's ancient civilization is where archeological evidence of prosthetics was discovered for the first time, where an eye prosthetic is found buried with a woman in Shahr-i Shokhta.

It was most likely composed of a bitumen paste that had a thin coating of gold applied on top of it.

Pliny the Elder also documented the story of Marcus Sergius, a Roman commander who, after having his right hand severed during a military campaign, had an iron hand fashioned to grip his shield so that he could continue fighting. Pliny wrote this story down. A well-known and very sophisticated

An Italian physician documented the presence of an amputee who still had an arm, and this arm gave him the ability to remove his hat, Please open his wallet, he must also sign his name.

Improvement in amputation surgery and prosthetic design came at the hands of Ambroise Paré.

One of his creations was a kneeling peg leg and foot prosthesis with a fixed position that was worn above the knee, adjustable harness, With a commanding knee lock position.

The effectiveness of his innovations served as a model for the development of prostheses in the future.

Other significant advancements made before the beginning of the modern era:

Pieter Verduyn was the first person to create a below-knee (BK) prosthesis that did not lock.

James Potts had a prosthesis that consisted of a wooden shank and socket, a steel knee joint, and an articulated foot. The prosthesis was operated by catgut tendons that ran from the knee all the way down to the ankle. It eventually became popularly known as the "Anglesey Leg" or the "Selpho Leg.".

A novel approach of amputating the ankle that did not entail first removing the limb from the thigh was developed...