The surgery to install (or what is called changing) the artificial knee joint is the final treatment for knee roughness and is considered one of the most successful surgeries in the field of orthopedics.
In this surgery, the patient is anesthetized. The worn out surfaces of the femurs and tibia (and soap in some cases) are removed and replaced with artificial parts so that the pain resulting from the friction of the bones disappears and the range of motion in the knee increases.
As for the duration of this surgery, it usually takes between 60 to 90 minutes.
One of the advantages of this surgery is that any curvature (curvature) of the leg is fixed through the same surgery, and the patient can walk on his leg the day immediately following the surgery with the help of crutches.
This surgery can be performed through a small incision. There are also modern techniques such as the three-dimensional joint used in some cases and the use of robots in performing surgery.
The artificial knee joint consists of a metal part that covers the surface of the femur and another that covers the shin, and between them is a white plastic material of high strength to prevent friction between them.
In a few cases, a plastic part may be installed covering the surface of the rump bone. These parts are usually fixed to the bones by means of a substance called bone cement .
There are types of artificial knee joints that are installed without medical cement, but their use is not common due to their high cost and the lack of proven distinction from cement joints.
Traditional industrial knee joints usually allow the joint to be bent up to about 110 degrees, which allows the patient to walk, climb the stairs, and get up from the chair naturally without any pain.
Frequently asked questions about knee replacement surgery:
Question: What is the success rate of knee joint replacement surgery and the expected life span of the joint?
Answer: About 90% of artificial knee joints remain in good condition for 15-20 years.
Question: What are the factors that affect the age of the joint?
Answer: There are factors that affect the life of the joint, including:
The patient’s weight. The accuracy of the surgery. Follow the patient’s instructions. And the quality of manufacturing the industrial joint itself.. And there is a recently published study in one of the largest scientific journals in the world in which the data of half a million patients who underwent artificial joint surgery were reviewed. It was found that after 25 years of installing an artificial knee joint, the artificial joint is still in good condition in 8 out of 10 patients. This percentage is very good.
Question: What happens after the end of the life span of the joint?
Answer: If a defect occurs in the function of the artificial joint after a long period of use, surgery is performed to remove the worn-out parts of the joint and replace them with new parts. In this surgery, bone grafts may be made or bone substitutes may be used to rebuild any bony part affected by the old artificial joint lift.
Question: What are the side effects (complications) of knee replacement?
Answer: This surgery is very safe, and the possibility of damage or complications usually does not exceed 5% of cases.
One of the possible complications is the occurrence of infection at the site of the artificial joint surgery, and therefore there is great interest in sterilization in these surgeries, and antibiotics are used preventively.. The patient is advised to bring the doctor immediately if there is swelling or redness at the site of the wound or a rise in temperature.
Another complication is clots in the veins of the leg, so the patient is usually given a medication for three weeks that helps maintain blood flow, and the patient is advised after surgery to do exercises that help avoid clots. The patient is advised to bring the doctor as soon as there is swelling in the leg or pain in the calves muscles.
Question: When does the patient walk after knee replacement surgery?
Answer: The patient stays in bed the first day after surgery to do exercises for the thigh muscles, then walks on his feet the next day directly with the help of a walker, and after a week the walker is dispensed with and the patient walks using one crutch for another week.. The patient usually stays in the hospital for about two days after the surgery. The sutures are removed two weeks after the surgery. The patient is also given medication and analgesics after surgery to help him avoid pain.
Question: If there is severe stiffness in the knees, is it possible to install an artificial knee joint on both sides?
Answer: It is common for there to be advanced roughness in the knee joints, and not in just one joint. Therefore, the patient may need to undergo surgery to install an artificial knee joint in both knees. Here, a trade-off is made between performing surgery on each side separately, or performing surgery on both knees at once.
The installation of an artificial joint in the knees in the same surgery has several advantages over performing the operation in two separate surgeries:
Exposure to anesthesia once (about 3-4 hours).
Less hospital stay.
One rehabilitation period (may be longer than one knee rehabilitation period only).
– Less cost than performing each knee in a separate surgery.
Knee surgery is preferred when:
The condition of the joints is so bad that surgery on only one side will not enable the patient to walk well.
If there is severe curvature of the legs, as performing surgery on one side and adjusting the curvature in it will lead to a large difference in length between the legs that does not allow the patient to walk normally.
It is not preferable to perform surgery on both sides at the same time in patients over the age of seventy-five or patients who suffer from other severe diseases such as heart and breathing diseases. In this case, the surgery is done on one knee, and then the surgery on the other side is performed after several weeks or months.
Question: Is it possible for a body to expel a joint and not accept it?
Answer: Since the beginning of the seventies, all artificial joints are made of materials that do not interact with the body at all.
Question: What is the appropriate age for joint replacement surgery?
Answer: Most of the patients who undergo this surgery are between the ages of 50 and 80. Artificial knee joint surgery can be performed starting from the age of forty, although it is preferable to delay the surgery if the pain is not severe enough to affect the patient’s lifestyle and prevent him from enjoying his life.
Knee replacement in cases of overweight:
Installation of artificial joints for patients who suffer from obesity (overweight). They are more likely to suffer from osteoarthritis, such as the knee and thigh joints. Roughness usually occurs in them at an early age and to a greater extent than in people who do not suffer from obesity. Some of these patients may need an artificial joint surgery, whether it is an artificial knee joint or an artificial hip joint. It is usually preferable for the patient to try to reduce his weight before the surgery, as performing the surgery in the presence of severe obesity may increase the chances of complications occurring during or after the surgery, such as clots and wound infection. Excess weight may also reduce the life span of the artificial joint. But the problem is that in many cases the patient cannot lose weight because of his inability to move as a result of the pain he suffers from, even if he diets. Over time, joint damage increases, pain increases, and mobility decreases, which leads to more weight gain.