What is an Artificial Knee?

The human knee joint is composed of the femur or tibia called the femur, calf, and fibula, and the sacrum. There is a cartilage disc between the femur and tibia, called the medial meniscus and lateral meniscus, respectively. The anterior lower femur has slots for the sacrum. The surface of these joints is covered with cartilage, which can absorb vibrations and bear pressure. Cartilage, especially the meniscus, is the most vulnerable part of the human body during exercise. Once the joint is damaged, it will cause joint pain and dysfunction. Artificial joint replacement can effectively reconstruct joint function and improve the quality of life of patients.

What is artificial knee joint

The artificial full knee joint includes a femoral prosthesis, a tibial prosthesis and a patella prosthesis, and a femoral condyle made of metal, a tibial tray and a tibial pad and a sacral prosthesis made of UHMWPE.

The artificial knee joint contains two parts, metal and plastic. The metal part includes the femoral, tibia, and metatarsal joints made of titanium alloy or cobalt chromium alloy. The plastic part is made of high-density polyethylene. Polyethylene was the first polymer material used for artificial joints. Later, it used ultra-high-performance polyethylene that adhered to the metal parts of the tibia and sacrum joints. The purpose is to reduce friction with the femoral metal articular surface.

Types of artificial knee joints

The fixation methods of artificial knee joints are mainly divided into two types: cemented and non-cemented. The most widely used are bone cement-fixed prostheses. In knee replacement surgery, the role of bone cement is not only to fix the prosthesis, but also to strengthen the bearing strength of the bone bed, especially on the tibial side. Non-cemented prostheses, such as various microporous or HA-coated prostheses, have achieved good follow-up results in the near future, but the lack of long-term follow-up cannot be compared with cemented prostheses. Physicians still recommend the use of cement to fix the tibial prosthesis.

Artificial knee arthroplasty

Knee arthroplasty includes monocondylar arthroplasty, knee arthroplasty, and hinged total knee arthroplasty. For purely medial or laterally spaced lesions, theoretically a single-sacral replacement can be chosen. The hinged total knee joint can be applied to total knee revision after knee tumor removal and loss of knee stability. According to the patient's situation, different length prostheses can be customized. The products are divided into simple hinge knee joint, femoral hinge knee joint, tibial hinge knee joint, and femoral tibial hinge knee joint.

Artificial knee joint

Artificial joint replacement is suitable for patients with severe joint pain, instability, deformity, severely restricted daily life and activities, and patients who are not effective or effective after conservative treatment. There are many kinds of diseases that can be treated by artificial knee replacement. The knee joint damage caused by trauma, osteoarthritis, ankylosing spondylitis, rheumatoid arthritis, knee varus or flexion contracture deformity, etc. Knee replacement to treat. Knee joints with active infection, tuberculosis, and severe muscle and neurological disorders are not suitable for artificial knee replacement. The optimal age for artificial knee replacement is 60 to 70 years old. With the continuous development of modern artificial joint technology and the improvement of surgical technology, the age of joint replacement has a younger trend.

How many years can the artificial knee joint be used?

The strength and abrasion resistance of artificial knee joint materials have been subjected to hundreds of abrasion tests. Generally, they can meet the needs of patients for more than 10 to 15 years. Choices, doctors' surgical techniques, and their own conditions. Currently, the orthopaedic community is working with engineers and materials scientists to continuously improve artificial joint materials, processes and surgical techniques.

How the artificial knee joint protects the artificial joint after surgery

The vast majority of patients undergo total hip replacement or total knee replacement surgery, the pain will be significantly reduced, the function is improved, and normal life can be restored, but the operation will not make the hip or knee function better than before the onset of disease.

After artificial joint replacement, it is necessary to develop good living and activity habits to maintain joint stability. Post-operative activities such as cycling, walking, dancing, swimming, and golf can be performed, but strenuous sports such as running and jumping, as well as long-distance walking, mountain climbing and other sports are not encouraged. High-impact contact sports should be prohibited. Excessive activity and weight loading will accelerate the wear of the prosthesis and cause it to loosen.

Once an artificial knee joint becomes infected or aseptically loosens, joint revision surgery is required. Revision surgery is more complicated than the first operation and may require bone grafts, replacement of joint prosthesis types, or the use of special prostheses. After revision, the vast majority of patients can obtain the desired surgical results.

New progress of artificial knee joint technology

Now, computer-aided design technology has been successfully introduced into clinical applications of artificial knee joints. With the help of software, doctors can simulate virtual joints on the computer exactly the same as the knee joints of patients, and use this model to find the best prosthesis for the patient in the joint prosthesis database.

Now using a navigation device in artificial joint replacement surgery, the entire joint is displayed on the screen in three dimensions, and its lesions are accurately understood to within 0.3 mm and 0.5 degrees. The tissue was loosened, and the prosthesis was installed under the precise positioning of the navigation system. The force line, function, and deformity correction of the prosthesis were detected and evaluated after installation. The position of the prosthesis is accurate, the fixation is firm and the function is good.

"Minimally invasive" is also a development direction of current knee replacement surgery. Minimally invasive surgery not only guarantees less trauma to the patient's body and fast recovery, but also meets the patient's requirements for the appearance of the surgical site.