Total knee replacement, is the replacement of the destroyed bone and cartilage in the knee joint with artificial biomaterials.
1. The artificial knee prosthesis has three components.
(1) A metal cast femoral condyle prosthesis.
(2) A metallic tibial prosthesis chassis and surface liner.
(3) Ultra-high polymer polyethylene articular surface prosthesis.
The femoral condylar prosthesis matches the surface of the joint liner perfectly, resulting in extension and flexion movements. More than 600,000 total knee replacements are performed worldwide each year.
2. Indications for total knee arthroplasty surgery.
(1) Various inflammatory arthritis of the knee joint (degenerative osteoarthritis, rheumatoid arthritis, hemophilic arthritis)
(2) Traumatic arthritis
(3) Osteoarthritis after high tibial osteotomy
(4) resting infectious arthritis (including tuberculosis, septic infection)
(5) Ischemic osteochondral necrotic lesions
3.Hospitalization process
When you are admitted to the hospital, the attending physician will take a detailed medical history and ask you to provide detailed information about your condition (including the presence of chronic diseases, hypertension, diabetes, coronary heart disease and rheumatism), as well as a history of drug allergies.
①Prepare for intraoperative and postoperative blood transfusion; complete the relevant procedures before surgery, including reading and signing the notification form, surgical consent form, preoperative interview form and anesthesia notification form.
②Sleeping pills may be given the night before the surgery to eliminate preoperative tension, and no food or water should be consumed after 8:00 p.m. until 6 hours after the surgery.
③Please hand over your valuables and dentures to your family for safekeeping.
④After entering the operating room, an intravenous line will be inserted into your arm to administer medication during the operation. A catheter will be left in place during surgery and will be kept for several days after surgery.
⑤ To reduce intraoperative bleeding, a tourniquet will be placed at the base of the thigh during surgery. Therefore, some patients may experience postoperative swelling at the root of the thigh or numbness and discomfort in the calf, and the symptoms will disappear quickly.
(⑥Try to keep your whole body, especially the skin near the incision, clean by taking a bath before surgery.
⑦After the surgery, you will be taken to the resuscitation room and the anesthesiologist will be by your side to encourage coughing or deep whistling to clean the lungs.
⑧After surgery, you can wear long elastic stockings on both lower limbs to prevent the occurrence of deep vein embolism in the lower limbs until the 8th week after surgery.
4.Postoperative rehabilitation exercise
Immediately after surgery, foot and ankle extension and flexion exercises can help prevent lower limb deep vein thrombosis.
Postoperative functional exercise methods are as follows.
①Quadriceps exercises: Tense your thigh muscles and straighten your knee joint as much as possible.
②Straight leg raise: Straighten and tense the knee joint in bed, and slightly lift the lower limb off the bed.
③Flexion and extension of the ankle joint: Rhythmically flex and extend your ankle joint.
④Rotate your ankle joint: Rotate your ankle joint from inward to outward or from inward to outward.
(5) Reclining knee flexion: Keep your heel off the bed, slide your lower leg proximally and flex your hip and knee as much as possible.
⑥Sitting knee flexion: Sit on the edge of the bed with your lower leg hanging down. The foot on the healthy side is placed in front of the ankle on the affected side and the affected limb is slowly squeezed to help flex the knee joint as much as possible.
(7) Straighten the knee joint: Sit on the edge of the bed with the lower leg hanging down. Using crutches, stand smoothly with both lower limbs, flex the hip and knee as much as possible at the same time, hold for 5 – 10 seconds, then straighten and repeat the exercise
⑧ To accelerate the postoperative recovery will use CPM machine to promote the lower limbs to reduce swelling and improve the venous blood flow in the lower limbs.
5.New behavioral norms
①Lose weight or control weight gain
②Under the guidance of the doctor, regular exercise will be performed to maintain the muscle strength and flexibility around the knee joint.
③Appropriately reduce the frequency of going up and down the stairs and single long-distance walking every day, and should learn to use a cane.
④Avoid falls and trauma, jogging and competition-type sports are not recommended, and avoid excessive squatting, which can shorten the life of the artificial joint by subjecting it to abnormally high stress.
⑤ Follow up with the hospital on time. If there is abnormal swelling and pain at the surgical site, redness, swelling, heat and pain at the local incision, reappearance of limb deformity, abnormal sound in activities, or feeling of knee instability, you should seek medical attention promptly.
If you have any other medical condition that requires medical attention or surgery after the artificial joint replacement surgery, even if it is some minor surgery (such as tooth extraction, dental implant or urinary catheterization), or if you have a small boil on your body, you should inform your treating doctor that you have received artificial joint replacement surgery.