Artificial knee joint

What is an artificial knee? An artificial knee is a prosthesis or implant made of metal and a special type of plastic that replaces a damaged, deformed, diseased, or injured knee joint due to arthritis or trauma. The surgery performed to replace the damaged knee with an artificial knee is known as knee replacement surgery. In this article, we will be discussing about an artificial knee. What is a knee joint? The knee joint is the largest joint in the body. It is formed where the femur or thigh bone and the tibia or shin bone meet. The knee joint is made up of tendons, cartilage, ligaments, lubricating fluid, and the kneecap (patella). What are the components of the artificial knee? An artificial knee joint implant is made up of metal alloys, strong plastic parts, and ceramic material. Up to three bone surfaces may be replaced in a knee replacement surgery, namely: The lower end of the femur: A metal femoral component can curve around the end of the femur. This component is grooved so that the kneecap may move up and down smoothly against the bone as the knee will bend and straighten. The upper surface of the tibia: This is a type of flat metal platform having a cushion of strong, durable plastic, known as polyethylene. Some implant designs may not have the metal portion, instead, the polyethylene will attach directly to the bone. The metal part of the component could have a stem that is inserted into the center of the tibia bone for additional stability. The back surface of the kneecap: The patellar component is dome-shaped and made up of polyethylene. It duplicates the shape of the kneecap. In certain cases, there is no need to resurface the patella. The components of the artificial knee are designed in a way so that the metal will always interface with plastic and provide smoother movement, resulting in less wear on the prosthesis. What are the materials used for an artificial knee joint prosthesis? An artificial knee is made up of the following different types of materials: Metal parts of the implant are made up of titanium or cobalt-chromium-based alloys. Plastic parts of the implant are made up of medical-grade polyethylene. Certain implants are made of ceramic or ceramic-metal mixtures like oxidized zirconium. These implants usually weigh between 15 to 20 ounces. What are the essential properties of an artificial knee joint implant material? The prosthesis material used as an artificial knee must have the following properties: Biocompatibility with the body Ability to duplicate the knee joint structures that need to be replaced High in strength Flexibility to bear stress without breaking Ability to move smoothly against each other Ability to retain their shape and strength for a long time What are the different ways to fix an artificial knee to the bone? The different ways to connect an artificial knee joint implant to the bone are: Cemented fixation: The artificial knee joint implants are commonly held in place by using fast-curing bone cement, known as polymethylmethacrylate. Cementless fixation: The artificial knee joint implants can also be press-fitted onto the bone. This type of fixation usually relies on the new bone growing into the implant surface. The cementless implants are made up of a material that will attract new bone growth. Most of these implants are coated or textured so that the new bone can grow into the implant surface. Hybrid fixation: This type of implant fixation uses a combination of cemented and cementless fixation. Your doctor will choose the artificial knee joint components and fixation method for you based on your condition. What are the factors that determine the design and brand of artificial knee joint used? There are many different types of artificial knee joint brands and designs available. The brand or design used for a particular case will depend on the following different factors: The need of the patient based on the type of knee problem present and the anatomy of the knee Age, weight, general health, and activity level of the patient Familiarity and experience of the doctor with a particular type of prosthesis Cost and success rate of the implant being used How long does an artificial knee joint implant last? According to research and some studies, about 80 to 85% of artificial knee prosthesis are known to function well even after 25 years of their placement. Conclusion: It may take some time for a person to get used to an artificial knee joint. It is therefore important to understand the type of recovery expected after knee replacement surgery and how an artificial knee can affect the day-to-day life of a person after surgery. The doctor will help you in recognizing any potential problems with the artificial knee and help you in managing them while maximizing the quality of your life after surgery.