What is Total Knee Replacement? Total Knee Replacement is an artificial joint replacement surgery, which is a treatment method to remove the joint surfaces that cannot be repaired by the body itself and replace the damaged joints with artificial joint parts, to correct the limb’s line of force, to eliminate the knee pain, to maintain the stability of the joints, and to restore the function of the knee joints. What kind of patients is artificial knee replacement suitable for? Artificial knee replacement is suitable for patients with severe osteoarthritis, ankylosing spondylitis, rheumatoid arthritis and other diseases resulting in knee joint destruction, knee inversion or flexion contracture deformity, such as knee joint pain, instability, deformity, and severe limitation of daily life and activities, and patients who are ineffective or ineffective in conservative treatment. Patients with active infection or tuberculosis in the knee joint, or with serious muscle and nerve dysfunction are not suitable for knee replacement. What age is suitable for knee replacement? The optimal age for artificial knee replacement should be 55-75 years old. With the continuous development of artificial joint technology and improvement of surgical techniques, as well as the increase of average life expectancy, there is a tendency to expand the age range for artificial knee replacement. Age is not the primary consideration for knee replacement, but is determined by the patient’s health and symptoms, and the degree of knee joint pathology. Artificial joint materials and service life The current artificial joint materials mainly include metal, polymer organic materials and bioceramics, these three types of artificial joint materials have their own advantages and disadvantages, and a reasonable combination of the three can maximize the life of the prosthesis, at present, for the mechanical properties of the higher requirements of the artificial hip joint of the head of the femur, the knee joint of the femur condyle of the surface, generally use cobalt chromium molybdenum, titanium alloy and other metal materials Composition; for the materials that constitute the joint surface, the requirements of a very good surface finish and wear resistance of the acetabular part of the artificial hip joint, artificial knee joint tibial platform part, more choice of ceramic, ultra-high polymer polyethylene material composition; there is also a fixation material called polymethyl methacrylate, commonly known as bone cement, used for the fixation of the artificial joint prosthesis and bone tissue. In recent years, new materials have been developed and applied to the clinic, such as new wear-resistant polyethylene materials, all-ceramic artificial joints and so on. How long can the artificial joint material be used? This issue has always been the most concerned about the patients, experts pointed out that the service life of artificial joints, mainly determined by two points, one is the wear and tear of the joints, artificial joints, the surface is very smooth, the natural wear and tear of the usual is very slow, but the patient’s joints need to be used every day after the replacement, day after day, there will always be slow wear and tear; the second is the wear and tear particles caused by the loosening of the prosthesis. The strength and abrasion resistance of artificial joint material is tested by hundreds of times of wear and tear, and high quality imported artificial joints can generally meet the normal use of patients for more than 20-30 years. With the development of material science, the service life of artificial joints used in clinical practice has been greatly extended. Of course, the service life of the artificial joint is also related to many factors, such as the patient’s primary disease, the quality of the local bone and soft tissue of the joint, the surgeon’s surgical technique, the design and material of the prosthesis, the patient’s use of the “new joint” and so on. According to the results of long-term clinical follow-up in foreign countries, under normal circumstances, the survival rate of 20-year prosthesis can reach more than 90-95%. However, in general, the younger the age, the heavier the weight, and the more active the joint, the shorter the life span of the joint. The orthopedic community is currently working with engineers and material scientists, among others, to continually improve artificial joint materials, processes and surgical techniques. And this technological advancement is certainly a boon to patients who choose joint replacement to improve their quality of life and want to move around in a healthy and pain-free manner. How to choose an artificial joint? Depending on the patient’s age, expectations of surgery, financial situation, and level of exercise, as well as the experience and recommendation of the joint surgeon, different types of prosthesis can be selected. Imported products are recommended. What are the complications and dangers of artificial knee replacement? Complications can occur with any surgery. It is important to assess the risks and complication rates of the surgery based on your condition and to treat and prevent them accordingly. Knee replacement is an intermediate orthopedic surgery, and there are a variety of complications that can occur: 1. Infection: including skin infection and deep wound infection. Preventive methods are preoperative, intraoperative and postoperative application of antimicrobial agents, aseptic operation and so on. Postoperative wound will have 1-2 drains to draw out the bleeding in the wound to prevent the wound from accumulating blood and infection, usually placed 24-48 hours after removal. 2, thrombosis: lower extremity thrombosis is more common, the vast majority can be cured. Preventive methods for the application of anticoagulants, the application of intravenous pumps, muscle contraction exercises. Lower limbs are elevated and fixed on a soft cushion to reduce pain and help blood return to the lower limbs to prevent thrombosis and swelling of the lower limbs. 3.Neurovascular injury: seen in cases with unclear anatomy or severe deformity. Fracture: intraoperative fracture is often seen in patients with severe osteoporosis, and postoperative fracture is mostly caused by trauma; 5. Loosening of prosthesis: mostly occurs in the distant period after arthroplasty. Pain or poor joint function after loosening of the prosthesis requires reoperation. 6, heart, lung and brain complications: less common, but can be life-threatening in serious cases. How to choose anesthesia for artificial knee replacement? Can choose lumbar epidural anesthesia, general anesthesia: lumbar anesthesia patients belong to the awake state, fast recovery, but the posture of the operation remains unchanged slightly tired; elderly patients, lumbar spondylolisthesis lumbar anesthesia difficult patients and their own requirements of patients can choose general anesthesia, sleep during the operation, wake up after sleep. According to the patient’s request whether to choose the pain pump. How is the surgery done? Surgery for “surface replacement”, removal of cartilage has been destroyed, growth of bone, synovium and a small portion of hardened bone cortex, implantation of metal prosthesis wrapped femur, tibia, implanted in the middle of the polyethylene cushion; to relieve the pain, restore the knee joint force line, increase the range of motion of flexion and extension. How bad is the pain after knee replacement? The pain will be more obvious on the first day after the operation, and the doctor will use analgesic medication or an intravenous pain pump to relieve the pain. It is possible to be almost pain-free after surgery, and the pain will gradually decrease after 24 hours. There will be some pain when you start the functional exercise, you can take oral pain medication, but it will be relieved soon. How long do I have to stay in the hospital for knee replacement? After 1-2 days of pre-operative examination and laboratory tests, if there are no contraindications to surgery, the knee replacement can be operated, and the stitches will be removed 14 days after the operation. Can patients with high blood pressure, heart disease and diabetes undergo knee replacement? Generally speaking, patients with high blood pressure, heart disease and diabetes should be cautious about undergoing knee replacement. If patients with high blood pressure can control their blood pressure within the normal range through medication and have no other complications caused by high blood pressure, they can have an artificial knee replacement. If there is a heart disease but the heart function is good, no serious arrhythmia and angina, etc., can also be joint replacement. Diabetic patients can have their blood glucose controlled within normal limits without serious complications caused by diabetes, and they can have knee replacement surgery. Diabetic patients have a higher risk of postoperative infection, so they should take long-term medication to control their blood sugar in the normal range after surgery. Patients with the above mentioned diseases need to undergo a complete pre-operative examination and have the relevant departments make a comprehensive assessment and treatment before considering surgery. Can I have both knees replaced at once? Yes, depending on the patient’s age and physical condition. Many patients with osteoarthritis have bilateral disease, and those who need joint replacement for both knees can be hospitalized at one time and operated at the same time, which not only reduces pain, but also reduces the cost and the number of re-hospitalization for surgery. The decision of whether or not to operate on both knees at the same time should be based on the doctor’s assessment and the patient’s own choice. Can an artificial knee be replaced after it has worn out or loosened? Yes, it is possible. The incidence is very low, but once the artificial knee joint becomes infected or loose, “revision surgery” is required. Specialized knee prostheses and surgical instruments are available. Revision surgery is relatively complex and may require bone grafting, changing the type of joint prosthesis, or the use of a customized prosthesis. After revision surgery, the vast majority of patients can achieve the desired outcome. How can I prevent fall trauma? 1. Falls can cause physical injuries and even life-threatening injuries. 2. When the patient is restless, unconscious or unable to take care of him/herself, the bed block should be pulled up to prevent falling out of the bed. 3. When changing positions, follow the “three-step process”: get up from the bed for at least 30 seconds, stand up for at least 30 seconds, and then walk again, and avoid sudden changes in position, especially at night. 4. 4. When you get out of bed and walk, you need someone to support you and wear non-slip cloth shoes. 5. It is recommended that you urinate and defecate by the bedside and do not go to the bathroom to avoid slipping and falling. 6. The first time you get out of bed after the operation, you need to get consent from the doctor in charge and have professional guidance. 7. After the operation, you need to use auxiliary equipment and have someone to accompany you. 8. If you have dizziness, black eyes, weakness of the lower limbs, unstable gait and other abnormalities when you are standing up or walking, please squat in place or lean against a wall and call others for help. 9. Please do not walk on slippery or uneven ground. 10. Please press the call bell when you need help, and the medical staff will give you timely help. How to prepare before the operation? Psychological preparation: understand the operation situation, reduce the patient’s fear of surgery; quit smoking and drinking 2 weeks before the operation; practice bed urination and defecation to prevent bed discomfort after the operation; keep the body clean, treat colds, pneumonia and other foci of infection; treat other diseases such as high blood pressure, heart disease and diabetes mellitus; preoperative instruction: first of all, strengthen the static contraction of the quadriceps muscle of the affected limb, as well as the active movement of the ankle, and ask the quadriceps muscle to hold each contraction for a certain period of time, so that the patient’s ankle can move actively and safely. The quadriceps muscle is required to hold each contraction for 10 seconds, and every 10 times is 1 group, and 5 to 10 groups are completed every day. The patient sits on the bed and performs straight leg raising exercise and ankle joint resistance flexion and extension exercise, the number of times can be determined according to the patient’s own situation, repeated 2 to 3 times a day. What are the precautions for diet after surgery? After about 6 hours after surgery, you can eat, gradually change from liquid, semi-liquid to normal diet; diabetic patients adhere to the diabetic diet, hypertension, hyperlipidemia patients with low-salt and low-fat diet; 2 weeks before surgery to quit smoking and alcohol; appropriate increase in protein, vitamins and other nutritious diets; eat more easy-to-digest food, vegetables, fruits (eg, bananas) to increase the fiber, to prevent and control constipation (and sit up more and reduce the time of lying flat); change the Change the misguidance of “you can’t eat seafood and fish after surgery”, eating more fish can increase protein well. Postoperative cold therapy role (1) small blood vessel contraction exudate reduction, conducive to tissue repair (2) sensory nerve fiber conduction velocity slows down, there is a more pronounced analgesic effect (3) to reduce muscle excitability, there is a better antispasmodic effect (4) local tissue metabolism is lowered, is conducive to the treatment of early inflammation and soft tissues (5) to reduce the excitability of the sensory nerves, muscle relaxation, there is analgesia (6) to eliminate the fatigue of the movement after the rehabilitation of the total knee arthroplasty purposes Through plyometric training, strengthen the muscle strength of flexor and extensor muscles around the knee, and promote the recovery of general physical strength and condition. Through walking or other coordination training, improve the muscle strength around the knee joint and its soft tissue balance and coordination, and ensure the stability of the joints Through joint mobility training, make the knee joint activities meet the needs of daily activities and some social activities Prevent postoperative joint adhesion, improve the blood circulation of the local or the whole lower limb, and avoid some postoperative complications Improve the patients’ mental and psychological outlook, and stimulate the enthusiasm for life. Rehabilitation program 1, the day of surgery: exercise of lung function, such as deep breathing and coughing, to prevent pneumonia. After the anesthesia disappears, ankle dorsiflexion and plantarflexion, toe movement 2, postoperative day 1: can take the sitting position, is conducive to coughing, prevention of pneumonia; upper limb exercise, is conducive to future walking exercises; isometric contraction of quadriceps muscle exercise 3, postoperative day 2: remove the drainage tube, take a picture to determine the appropriate position of the prosthesis, the use of the CPM (lower limb mobility device) to carry on the functional exercise. Starting from 30º passive knee flexion. At this time, you can get down to stand, walk with your leg elevated, and actively and passively flex or straighten the knee. Within 1 week, try to make the knee flexion at or above 90. To practice straight leg raising, the healthy foot can be placed under the affected limb to help raise the affected limb. The affected limb should do static contraction of quadriceps muscle, hold it for 10 seconds each time, every 10 times is 1 group, 10 groups per day; the patient sits on the bed, the affected limb should do straight leg raising exercise, no lifting height is required, but there should be a stagnant time of about 10 seconds; 4. 3-7 days after operation: walk 50-100 meters; knee joint passive activity flexion 100-110º, active activity flexion 80-90º; straight leg raising should be done at or above 90; the affected limb can be put under the healthy foot to help lift it. Ordm;; straight leg raising muscle strength is grade III (manifested as the ability to actively lift the leg) 5, 8-14 days after the operation: knee passive activity flexion 120º, active activity flexion 90º more than 0º; muscle strengthening exercises, riding a stationary bicycle for 15-20 minutes, able to go up and down the stairs How to practice lifting the leg From the first day after the operation, you have to practice lifting the leg. Specific practice foot: first force to make the back of the foot hooked upward, and then force to straighten the leg, and then lift the whole leg to half high, maintain at this height for 10 seconds and then put the leg down, and completely relax, above for a practice. Exercises should be carried out in groups, each group 5~10 times, 3~5 groups per day. The specific amount of exercise depends on the physical condition. If the amount of exercise is too large at the beginning, pain in the back of the legs will occur. How to practice leg bending At the beginning, practicing hitting the bend can be done on the side of the bed. The leg can reach 90 degrees by virtue of gravity hanging under the bed. Then use the healthy limb to put the affected limb in front of the calf, to help backward pressure, can increase the angle of bending the knee. The amount of force should be tolerated, and it is better if the force can be maintained for a few minutes. How to do the leg press exercise Put your leg straight on the bed, and put your hands on top of the knee, gently press down, make your leg as straight as possible, each time to maintain about 5 minutes, this is the best way to exercise leg straightening. How to master the amount of exercise The amount of training from small to large, step by step, in order not to cause the affected knee obvious pain, swelling and discomfort is appropriate. The daily flexion and extension activities are not in quantity, but in quality. Try to straighten and flex the joints to a certain extent so that there is progress every day, and if the number of activities is too high, joint swelling will occur. If this happens, the number of flexion and extension activities must be reduced. Swelling usually occurs within 3 months after surgery when there is too much activity. How do I continue my rehabilitation after discharge from the hospital? After discharge from the hospital, continue to take the initiative to do straight leg raising and resistance exercise to strengthen the muscle strength; extend and flex the knee to increase the range of motion of the joint; gradually reduce the use of crutches and walking aids, and you can walk independently after 2-3 months. Daily precautions after knee replacement? Appropriate rest and exercise Continue to perform straight leg raising, walking, knee extension and flexion exercises, ankle active dorsiflexion and plantarflexion activities, and gradually perform up and down stairs exercises depending on tolerance. Pay attention to the gradual increase of your activities, avoid too much exertion, have a moderate amount of rest after exercise, so that the joints in the normal posture as much as possible to relax 2, continue to take oral anticoagulation of Berytol for 10 days. 3.Pay attention to safety during activities and prevent trauma. Maintain ideal weight to reduce the burden on the knee joint. 5.Daily activities should avoid excessive burden on the knee joint to reduce the chance of wear and tear of the joint, such as using a cart instead of a handheld for overweight things, and utilizing handrails on stairs more often. 6, after knee surgery, please try to avoid the following movements: squatting; climbing; running; lifting heavy objects; walking long distances. 7, abide by the physician to give you activity restrictions, until the next follow-up. 8.Six months after surgery, you can swim, ride a bicycle and return to normal life. 9.If you have the following conditions, you should go to the doctor immediately: when the wound is inflamed and there is secretion; when the pain worsens; when the knee joint is injured and causes difficulty in walking. 10.After surgery, it is normal to take pictures once every 1-2 years to keep the information and review for comparison. Normal phenomena after knee replacement 1. Why is there a “numbness” or “electric shock-like” pain around the wound? This is due to the regeneration of the nerves that innervate the skin on the outside of the incision, and does not affect daily activities or rehabilitation training. 2. Why is there swelling and warmth in the joints and how long does it take to recover? Within 3 months after surgery, the knee joint of the affected limb often has the symptom of low-grade warmth, and the floating patella sign is weakly positive. This is the body’s reaction to the replacement prosthesis or due to stimulation of the knee joint during functional training. This inflammation is not caused by bacterial infection, but there are redness, swelling, heat, pain and other symptoms; swelling is caused by joint fluid, a small amount of joint fluid can play a lubricating role, which is conducive to joint activity, a large amount of joint fluid can be extracted by arthrocentesis. The above symptoms can disappear gradually within half a year after surgery. 3.Why does the affected limb have pain or soreness at night and stiffness in the morning before getting up? During the postoperative rehabilitation process, with the increase of training intensity and frequency, some patients may experience joint pain at night and stiffness in the morning, especially during the daytime when they are more active. The intensity of the pain is related to the functional status of the knee joint before surgery. The lower the functional score of the knee joint, the more pronounced the pain triggered by training may be. 4. Why do I always feel tightness around my knee? This is mainly due to postoperative scar formation, which can be gradually pulled away through exercise, and the feeling will disappear. 5.Why is there stiffness or unnaturalness when walking? After knee replacement surgery, as long as the patient can take care of his/her own daily activities without joint pain symptoms, and the joint flexion and extension reaches the expected level, it can be considered to have achieved the expected results. Early postoperative stiffness is normal, and usually can be relieved to different degrees in 6-8 weeks, and the knee mobility is basically restored in 3 months after surgery. 6. What is the “coughing sound” in the knee joint during some patients’ activities? This sound is generally due to the installation of the soft tissue around the prosthesis is still flaccid, muscle weakness, lack of sufficient power to maintain balance. The sound is caused by collision between the prosthesis during movement, especially between the hip bone and the femoral condyle. This sound is rarely clinically symptomatic, but can cause psychological tension in the patient. With the passage of time, after the soft tissue repairs its own balance, this sound will gradually disappear. However, when the symptoms are obvious, you should consult with a professional doctor to exclude the possibility of hip bone slipping. In conclusion, the above phenomenon belongs to the normal reaction in the rehabilitation and functional training after artificial total knee replacement, and the patients do not need to worry too much about it, so as to lose the courage and confidence in further rehabilitation treatment, which will affect the recovery of joint function after surgery. After discharge from the hospital, in addition to taking the opportunity of outpatient review to listen to the professional doctor’s assessment of the prosthesis and the functional recovery of the affected knee, the patient should consult the professional doctor in time to make the corresponding identification of other problems in the process of late rehabilitation. What should I do if I have to go to the hospital immediately? Late postoperative infection is the most serious complication after artificial joint replacement, and in severe cases the prosthesis may even have to be removed, thus easily leading to complete failure of the artificial joint. Symptoms of infection are usually obvious localized warmth, redness or more fluid in the affected knee joint. When the patient has a cold or an acute infection in other parts of the body, antimicrobials should be given to prevent the occurrence of advanced infections; if the affected knee is found to be locally red, swollen, or with a “red packet” protruding, antimicrobials should be administered and the patient should go to the hospital immediately, and never go to the local non-specialized clinic to avoid delaying the condition or wrong treatment.