Introduction
Common types of medical implants are ar-throplastical prostheses, or joint replacements, which serve to take over joint functions for patients suffering from musculoskeletal dysfunction or severe pains in e.g. the knee, hip (see Figure 1), or shoulder. Joint replacements generally consist of multiple parts made of different materials. The common hip joint re-placement prosthesis shown in Figure 2 consists of a metal ball, socket and stem and a plastic spacer. The metals used are mostly CoCr, austenitic stainless steels, Co–Cr–Mo alloys and Ti or Ti alloys, for their hardness, corrosion resistance, fracture toughness, low modulus and good machinability [1, 2]. The plastic spacer is typically made of polyethylene. The prosthesis is secured to the host body through either press-fitting or cementing .
Biocompatibility of a material refers to “(i) an appropriate response of the host tissue and living system to the material, and (ii) the response of the material due to contact with living matter” [1]. A lack of biocompatibility can have an undesirable effect on the functionality of prostheses due to e.g. metal toxicity or sensitivity and osteolysis.
Figure 1. X-ray image of a pelvis with total hip joint replacement [3].
Osteolysis is the loss of bone due to polyethylene wear debris. Small parts of polyethylene from the prosthesis lead to inflammation , which in turn may cause loosening of the implant–tissue interface [4]. Loosening may also occur due to wear debris or fatigue of the cement or metal, leading to painful implant movement inside the bone.
Figure 2. Typical metal-and-plastic ball-and-socket hip joint replacement prosthesis
[www.ntmc.go.jp.e.eo.hp.transer.com/p_other/contents/66.htm].
Corrosion o...
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...lectric field over the electrolyte leads to the deposition of the oxide film onto the base material;
2 Locally increasing the voltage over the electrolyte until a critical value is reached results in local breakdown of the oxide film and locally changes the TiO2 layer structure (within 1 ms);
3 Subsequent repetition of (2) over the entire film surface leads to the modification of the entire TiO2 film.
The resulting modified film can be divided into two layers — the inner layer (of thickness ~15 µm) is hard and highly abrasive and protects the base material, while the outer layer (of thickness 10–20 μm) is porous and worn out relatively easily but promotes tissue generation. Moreover, application of Ca2+- and PO43−-containing electrolytes leads to the incorporation of Ca and P ions into the film, in turn providing in nutrition for new tissue generation [12].
Technology nowadays is getting more and more dangerous, especially to our ears. Every day we are subjected to videos, text sounds, alert sounds, alarms, and anything else that may be of use in life. These sounds seem to be happening more often which is damaging our ears. There is a solution to this damage though, and that is cochlear implants. These implants will bypass the damaged part of your ear to give you a sense of sound that can be made very useful to the patient. This paper will look into how the ear works, how hearing loss happens, why these cochlear implants are a good solution, how these implants work, cost and ethics related to these implants, and what the future holds for them.
Despite these advantages there are concerns which affect patient’s and surgeon’s decision to undertake metal-on-metal hip resurfacing arthroplasty. These issues range from being technically demanding, stringent patient selection criteria (11), high early incidence of femoral neck fractures(12, 13) and reported risk of high circulating metal ions(14-17). There are theoretical concerns about cancers following exposure to high levels of cobalt and chromium ions (18).
Alumina and zirconia ceramics have been widely used in orthopaedic hip replacements for the past 30 years. The advantage of using these was lower wear rates than those observed using polymers and metals. Because of the ionic bonds and chemical stability of ceramics, they are relatively biocompatible and therefore more preferable to use than metals and polymers. Alumina is most commonly used as a femoral head component instead of a metal in a hip prosthesis because this would reduce the polyethylene wear that is generated. Alumina is a desirable biomaterial to use in hard tissue implants because of characteristics like excellent wear resistance, high hardness, bio inert, low abrasion rate and good frictional behaviour. Furthermore, it has excellent surface finish as well as high fatigue streng...
Prosthetic care goes back to the fifth Egyptian Dynasty. The basics of prosthetics started out with crutches. They were made of wood and leather for more comfort. A wooden toe was a big deal because it helps balance and perform a function to help you walk. Next peg legs and hooks were used. Fibers were used to have a sense of wholeness but weren’t functional. By the second or third peg legs cooper and wood were used. Later on iron was used but was inconvenient because of how much it weighed. Inventions have been worked on and expanded for example, the fixed position foot. Other inventions have become obsolete over the years like the use of iron, hand hooks, and peg legs ("The History of Prosthetics).
Prosthetics (pronounced prahs-THEH-tiks) is the branch of medicine that deals with the artificial replacement of a missing body part. A prosthesis (pronounced prahs-THEE-sis) is the general term for the artificial part itself that replaces the body part usually lost to disease or injury. Prosthetics has a long history, and recent design advances that use battery power and new lightweight composite materials are making prostheses better and easier to use.
...Havelin, L., Furnes, O., Overgaad, S., & Engesaeter, L. (2012). Increasing risk of prosthetic joint infection after total hip arthroplasty. Acta Orthopaedica, 83(5), 449-458.
The materials in prosthetic limbs have always evolved along side technology, usually changing for the better. Prior to the development of electronics and plastics,
...ment and to focus more on the different non-invasive interfaces which will help us deal with the versatility issues of the device. Finally, I recommend that the group looks further into the different interfaces and materials that prosthetics can be used combined with in order to erase the control issue that come with prosthetics.
... middle of paper ... ...3). The prosthetist pays careful attention to the structure of the patient’s residual limb, including where the muscles, tendons and bones are located (Clements para 3). He also takes into account the health of the patient and the condition of their skin (Clements para 3). After the prosthetic is made, the prosthetist still has the task of making adjustments.
The main topic of this essay will be about the in-depth research into medical prosthetics
The modern total hip replacement was invented in 1962 by Sir John Charnley. Sir Charnley was an orthopedic surgeon who worked for a small hospital in England. The total hip replacement is considered by many to be the most important operation developed in the 20th century, solely based on the fact that it helps to relieve human suffering. Total hip replacement was first performed in the United States around 1969. Since then there have been more then a hundred of thousands of replacements performed in the United States. One of the first surgeons to perform this surgery was Charles O. Bechtol. In 1969, while he was a professor at UCLA, Bechtol started a total hip replacement program. The artificial hip joint is considered a prosthesis. There are two major types of artificial hip joints, cemented prosthesis and uncemented prosthesis. The type of prosthesis that will be used on the individual patient is decided by the surgeon depending on the patient's age, lifestyle and the experience that the surgeon has with a particular one.
Prosthetics are used by people that are born without complete limbs and who have had amputations due to war, diseases or accidents to function and be seen as a “whole” by the society. Throughout the years, since the first invention, people have been developing and enhancing limb prosthetics to produce a device that would be functional and aesthetically pleasing for people who have had amputations. There are many materials that have been used to manufacture limb prosthetics, such as wood, copper, and bronze, but nowadays, lighter materials, namely carbon fiber are being used for comfort. Because of prosthetic enhancements, the perceptions of people toward amputees have shifted from negative to positive; people are becoming more appreciative rather than
These include nylon resin material, acrylic resin and metal. They use metal covered in plastic with plastic teeth for making partial dentures.
The idea of having an amputated limb and being able to receive a prosthetic limb within a few short hours is still a dream in today’s world. Scientists and researchers have made huge leaps and bounds in recent years, but prosthetic limbs have been around for decades. The oldest ever found was in Cairo, Egypt in the year 2000. It was a prosthetic toe made of leather and wood from 3000 years ago (Clements, 2008). This limb showed us that for the most part prosthetics have not changed a whole lot, but how they are made has improved. Prosthetic limbs can now be designed by using CAD/CAM, computer aided design and manufacturing. They can speed up the process it takes to make the limbs for patients. Clinical use of this process is still slow to get going in a lot of states and the world. The most important part of the prosthetic limb to the patient is not whether the limbs functionality is better, but the comfort of the socket. The socket is where the residual limb will reside in the actual prosthetic limb. When the handmade casts are used, it is hard to make a socket that will work well for the patient because it is hard to make an exact replica of the limb. That is why more funding needs to go to places that will teach people how to use the CAD/CAM design process and to help companies buy the expensive fabrication sites to actually make the limbs. Not only is the use of CAD/CAM a better process, but it is faster and will get the patients a better fitting limb that they will want to use more often.
Today there is a great need in advances in the field of prosthetics. This demand is being generated in large measure by wounded veterans needing prosthetics. While new advances in body armor is saving lives, it is also leading to many limb injuries in soldiers who would not have usually survived. In the first two years of the Iraq war, over 200 soldiers lost limbs.