What is total knee replacement surgery?
The joints are the main structures of the body’s movement and are the “links” and “bridges” that connect the bones. Of the many joints in the body, the knee joint plays a pivotal role in people’s daily lives. It bears the majority of the body’s weight and is one of the more loaded joints in various activities of the body.
As the saying goes, the legs get old before the person gets old. After middle age, these tissues become degenerative and no longer as tough and elastic as in youth, and the synovial fluid secretion in the joint cavity decreases, making it more prone to various strains and lesions.
Contemporary total knee replacement surgery began in the 1960s and has become one of the most important breakthroughs in orthopaedic surgery in the 20th century. Total knee replacement is the replacement of damaged bone and cartilage in the knee joint with artificial biomaterials, which simply means that the worn and damaged joint surface is removed and an artificial joint is implanted. It not only effectively relieves the pain of the patient’s joint, but also restores the normal function of the affected joint, thus improving the patient’s quality of life.
As people’s standard of living continues to improve, their perceptions change and the society ages, more and more patients are willing to undergo total knee replacement surgery in order to pursue a higher quality of life. Currently, more than 40,000 total knee replacement surgeries are performed nationwide each year.
What types of patients need joint replacement surgery?
Total knee replacement surgery is indicated for patients who have severe lesions in the knee joint or who have recurrent episodes of joint pain, swelling, deformity, and joint instability that seriously affect their daily life and for whom conservative treatment has failed or is not effective. Specifically, these include.
1, various inflammatory arthritis of the knee joint, including degenerative osteoarthritis, rheumatoid arthritis, hemophilic arthritis, etc.;
2, a few traumatic arthritis;
3, benign synovial tumors or bone tumors of the knee joint;
4, osteoarthritis after failed high tibial osteotomy;
5, Patellofemoral arthritis in a few elderly people;
6, resting infectious arthritis (including tuberculosis, septic infection);
7, a few primary or secondary osteochondral necrosis diseases.
It must be emphasized that total knee arthroplasty is not a perfect procedure, and although the majority of patients have satisfactory results, attention should be paid to the selection of indications so as not to affect the outcome.
What are the benefits of total knee replacement surgery?
Total knee replacement surgery is a major breakthrough in the history of human medicine. The vast majority of patients who undergo total knee replacement will receive the following benefits.
1. The greatest benefit is the elimination of joint pain and a significant improvement in joint function.
2. Increased strength in the legs. As knee pain disappears, you are able to use your legs more, which strengthens your muscles.
3. Quality of life improves. You are able to go through daily life with ease and can participate in some sports.
4. Long-lasting pain-free activities. The vast majority of imported artificial joints can be used for more than 20 years.
History and current status of artificial knee replacement
In the late 1960s, a Canadian doctor, Frank Gunston, invented a multi-axial knee prosthesis and was the first to use bone cement to fix the prosthesis, which is how the history of modern artificial knee replacement really began. This was the first time that special surgical instruments were used to achieve precise osteotomy and prosthesis placement.
Since then, as the biomechanics of the knee joint has been studied, the design concept of artificial knee prostheses has been updated, and prosthetic materials have been improved, the focus of prosthesis design has shifted from purely hinged prostheses to semi-restricted and non-restricted prostheses.
Nowadays, computer-aided design technology has been successfully introduced into the clinical application of artificial knee joints. With the help of software, physicians can simulate a virtual joint on the computer that closely resembles the patient’s knee and use the model to search a database of joint prostheses to find the best prosthesis for that patient.
After decades of development, artificial total knee replacement is now considered one of the most effective and successful procedures for the treatment of end-stage or severe knee osteoarthritis. Currently, more than 40,000 total knee replacement surgeries are performed nationwide each year.
Also, with advances in technology, artificial knees are lasting longer and longer.
How is total knee replacement surgery performed?
Once total knee replacement surgery is determined, your surgeon will determine the specific surgical plan and anesthesia plan based on your physical condition, x-rays and other ancillary tests after completing the necessary preoperative preparations.
In order to minimize intraoperative bleeding, a tourniquet will be placed at the base of the affected thigh before the surgery is performed. Therefore, some patients may experience post-operative swelling at the root of the thigh or numbness and discomfort in the lower leg. These symptoms will disappear quickly and there is no need to worry too much.
After anesthesia, the surgeon will sterilize your knee joint. Once there is sufficient surgical exposure, special tools and precision instruments will be used to remove the damaged joint surface, and the stump will be trimmed and a prosthesis will be placed.
A normal total knee replacement surgery usually takes 2 to 3 hours to perform. Once the surgery is complete, you will be taken to a wake-up room to wait for consciousness to return and then return to your room once you are fully awake and stable.
What do I need to do before and after surgery?
When you are admitted to the hospital, your attending physician will take a detailed medical history, understand your general condition and the extent of local knee disease, and determine if you have any indications for arthroplasty. After excluding any contraindications to surgery, a suitable artificial joint will be selected. Your x-rays will be taken and the right size joint will be selected. At the same time, you must complete some of the following necessary preoperative preparations.
1.Diabetes, heart disease or hypertension and immune diseases (such as rheumatoid arthritis, systemic lupus erythematosus, etc.) should undergo systematic medical treatment to make the condition smoothly controlled before surgery.
2.If there is a systemic occult infection lesion (such as tinea pedis, ringworm, otitis media, sinusitis, etc.), the chronic lesion should be treated promptly before undergoing joint replacement surgery.
3. Stop using non-steroidal drugs (such as aspirin, fentanyl, furosemide, intravenous, etc.) and immunosuppressive drugs 2 weeks before surgery to avoid intraoperative and postoperative bleeding, which may affect wound healing or impair renal function.
After surgery, there will be some pain and swelling in the knee, and the use of some pain medications can relieve these discomforts. 3 to 4 days later, the postoperative pain and swelling will be largely eliminated. You should tell your primary care physician if you experience any unusual numbness, loss of sensation in the lower leg or inflexibility in toe extension and flexion.
If a drain is left in place during surgery, it is usually removed 48 to 72 hours after surgery. When the drain is removed, the patient is usually asked to wear long elastic stockings on both lower extremities as an effective adjunct to prevent postoperative deep vein embolism in the lower extremities until 8 weeks postoperatively.
After the drainage tube is removed, the rehabilitation physiotherapist will instruct you to perform muscle exercises for knee flexion and extension to help you resume knee extension and flexion as soon as possible. You will be discharged from the hospital 2 weeks after surgery. After discharge, your rehabilitation will continue.
Three months after discharge, you will have to go to the hospital for a review to take x-rays to see if the position and stability of the joint prosthesis is good. You will be re-examined six months after surgery and then followed up for a long time. If you feel uncomfortable, such as redness, swelling, pain or difficulty in moving the joint, or if the hip joint is injured due to an unexpected situation, go to the hospital promptly for examination.
How should I do rehabilitation after surgery?
For patients with total knee arthroplasty, post-operative rehabilitation is essential for the recovery of the knee joint function. Gradually strengthening rehabilitation exercises after surgery can restore walking ability as soon as possible and avoid joint dislocation.
1 to 3 days after total knee arthroplasty: Patients with heavy pain are generally not advised to move the affected joint. They can elevate the affected limb, actively extend and flex the ankle and interphalangeal joints as much as possible, and start muscle contraction training for quadriceps and other muscles for 3 to 5 minutes every hour to promote blood flow back and prevent thrombosis.
4 to 14 days after artificial total knee replacement: The patient’s pain has been significantly reduced. At this time, the main purpose of rehabilitation exercises is, to promote the movement of the knee joint. If possible, joint movement can be trained with the help of a continuous passive knee mobilizer (CPM) under the guidance of a physician.
2 weeks to 6 weeks after total knee arthroplasty: The main purpose is to train the strength of the quadriceps muscle. At the same time, training to maintain joint mobility. The main methods are: the patient sits on the edge of the bed and actively straightens the lower leg several times, gradually; the patient sits on the bed with a pillow under the knee off book to flex the knee joint, and then actively straightens it. Walking and going up and down stairs itself is also a rehabilitation exercise for muscle and joint function.