I. Rehabilitation goals after total knee replacement: (1) Prevent bedsores. (2) Prevention of deep vein thrombosis and pulmonary embolism. (3) To restore full knee mobility. (4) To strengthen the muscles around the knee joint and stabilize the knee joint. (5) Accelerating the progress of the patient’s walking with crutches or independently. (6) Restore the patient’s ability to perform independent activities of daily living. (7) Improve the quality of life. Second, the rehabilitation program after total knee replacement: 1. The difference between the day of surgery and the first day after surgery: (1) The day of surgery: refers to the day of surgery, which can also be called day 0 after surgery. (2) The first day after surgery: it refers to the day after the patient’s surgery, for example, if the patient is operated on Monday, Monday is the day of surgery and Tuesday is the first day after surgery. (2) Recovery on the day of surgery: (1) Routine antimicrobial anti-infection treatment, which lasts until 7-10 days after surgery according to the patient’s body temperature. (2) Routine low molecular heparin to prevent deep vein tether formation, lasting until 10 days after surgery. (3) Elevation of the affected limbs, observation of the dressing oozing blood and negative pressure drainage. (4) Deep breathing exercises. (5) After recovery from anesthesia, active muscle contraction and relaxation exercises for both lower limbs should be performed as often as possible. (1) Continue to control edema. (2) Continue anti-infection treatment. (3) Place a towel roll at the ankle joint and keep the knee in a straightened state. Because patients with severe osteoarthritis usually have years of limited knee extension, the posterior joint capsule and the muscles and ligamentous tissues behind the knee are mostly shortened. At the beginning of the practice of heel pads under the towel roll knee extension will feel the back of the knee joint is pulled very difficult, if still can not stand, you can rest a little and then continue to practice, however, the rest time is not too long. The pain of practicing knee extension will be significantly reduced after 3 days. (4) Walking with crutches with the help of a therapist, 1 time/day. Walk with one-third of the weight of the affected limb, not more than one-third of the weight. If the patient is not accustomed to walking with crutches, he/she can also walk with a walker. The first day of walking does not require the patient to walk for how long and how much distance, the main purpose is to exercise the patient’s first postoperative out of bed, standing with the help of crutches and a few minutes of activity at the bedside or in the ward. (5) Ankle pumping exercise: the patient does ankle plantarflexion (toes and instep hooked upward) and dorsiflexion (toes and instep hooked downward) exercises by himself, which is very important for preventing phlebitis of gastrocnemius venous plexus and deep vein thrombosis of the lower limbs in the elderly after the operation. The method is as follows: the patient straightens both lower limbs while lying in bed, relaxes both ankles naturally, and then performs dorsiflexion, which must reach the maximum limit when dorsiflexion is performed. Then start to do plantarflexion from the maximum dorsal extension state, and plantarflexion should also reach the maximum. This should be done repeatedly. In the process of watching TV, reading books or newspapers in bed and talking with family members, the patient can continuously perform plantarflexion and dorsiflexion exercises. (6) On the first postoperative day, the patient should also start to perform a moderate amount of contraction and relaxation exercises of the quadriceps muscle. The method of quadriceps contraction and relaxation exercises while lying in bed: the patient lies on the bed with legs naturally straightened, and repeatedly performs the activity of contracting the thigh muscles of both lower limbs for 5 seconds and then relaxing them for 2 seconds. The number of contractions and relaxations per day totaled 3 groups, 50 times per group, a total of 150 times. (7) At the end of the first postoperative day if the patient had a urinary catheter inserted before the operation, the catheter should be removed. (8) In the immediate postoperative period, a negative-pressure drain should be placed in the joint and in the incision, and it should be pressure-wrapped with a large cotton pad in order to minimize postoperative bleeding. By the second postoperative day, both negative pressure drains should be removed and the large cotton pads with pressure bandages should be removed at the same time. This will make it easier for the patient to get out of bed because of the removal of the urinary catheter, the drainage tubes and the removal of the cotton pads. (9) The inflatable therapeutic device is used from the second day after the operation when the drainage tube is removed. Its principle is to promote the venous blood circulation of both lower limbs through microcomputer-controlled inflation and suction to prevent thrombosis and promote the swelling to subside. The insufflator was used until nearly 2 weeks after the operation. (10) On the second postoperative day, the patient can walk on the ground for a longer period of time and distance, and can go out of the room for a certain distance on the basis of the first postoperative day, and then go back to the bed. 4. 3-7 days postoperative rehabilitation: (1) Continue the above edema control and anti-infection treatment. (2) The patient’s postoperative pain has been significantly reduced, and start to practice CPM (knee passive mobilizer), starting from 50° knee flexion on the third postoperative day and increasing by 10° every day, i.e. 60° on the fourth postoperative day, and CPM practice to 70° on the fifth postoperative day, 80° on the sixth day, and 90° on the seventh day. Flexion of the knee to 90° was performed one week postoperatively. The above CPM exercises were performed three times a day for 1 hour each time. (3) In addition to the above CPM exercises, considering that the angle set by the CPM is often 10-25° less than the actual knee flexion angle, the rehabilitation therapist or the patient (in hospitals where there is no rehabilitation therapist) should personally help the patient to practice flexion of the knee to 90° once a week after surgery. (4) Gradually increase the walking distance from three days after the operation, and when walking, the weight bearing is still one-third of the body weight, and one week after the operation, i.e., seven days after the operation, the patient can fully bear weight. One week after the operation, you can go to the toilet by yourself with the help of crutches, and then return to the hospital bed by yourself. (5) Strengthen the lower limb muscle contraction and relaxation exercises. Start practicing straight leg raising on the third day after surgery. For the first time of practicing straight leg raising, patients are only required to be able to endure the pain and complete the straight leg raising movement. On the fourth postoperative day, depending on the patient’s physical strength and fitness level, the patient can complete the straight leg raising movement 2-4 times. From the fifth day to the seventh day after surgery, practice 4-6 times a day according to the patient’s condition. 5. Postoperative rehabilitation from 8 days to 2 weeks after surgery: (1) From 8 days to 2 weeks after surgery, patients should continue to practice CPM 3 times a day for 1 hour each time. The angle of the exercises can vary according to the patient’s ability to tolerate the pain, but it must be above 90° of knee flexion, and the maximum angle should not be greater than 110°. During this period, if the angle of knee flexion is greater than 110°, most patients will feel very painful, and, for some patients with poor wound healing ability, there is also a risk of wound tearing and secondary infection. (2) This is also a period of high incidence of thrombosis, so do not relax the ankle pump exercises described earlier. (3) Continue to use the cuff to prevent thrombosis, and use the cuff until 2 weeks after surgery. (4) During this period, the patient should be able to walk independently with the aid of crutches. In addition to performing independent early morning washing, gargling, going to the toilet, and other simple activities of daily living, the patient may add a short daily walk around the ward. (5) Discontinue the use of antimicrobials 7-10 days after surgery according to the patient’s body temperature. (6) Routinely discontinue low molecular heparin 10 days after surgery. (7) Begin to practice the strength of both upper limbs, either by dumbbells on the bed, or by hands on the left side of the bed in a left-handed downward lateral position (mainly left-handed), or by hands on the right side of the bed in a right-handed downward lateral position (mainly right-handed). Upper extremity strength exercises can increase the ability and ease of walking with crutches. (8) Begin strength training for the low back muscles. For the elderly, a long period of bed rest after surgery is a big burden on the lower back. Strengthening the lumbar and back muscles can significantly enhance the patient’s ability to carry out daily life activities, and also improve the patient’s mental status and enhance the self-confidence in restoring health. 6, 3 weeks after surgery: (1) Patients are discharged from the hospital at the beginning of the third week after surgery, i.e. 15-17 days after surgery. (2) Start practicing patellofemoral activity by placing the fingers of both hands on the upper and lower edges of the patella and both sides of the patella, and pushing the patella upward, downward, and to both sides respectively. Patellofemoral activity is very helpful to improve the flexion angle of the knee joint after surgery, and the patient must practice it carefully. It can be practiced several times a day while resting in bed. Pushing the patella should be done with some force and the patellar mobility should be large enough to be effective. (3) Begin to walk independently without crutches for short periods of time, 5 minutes each time, but hold the crutches with both hands for protection at all times, without the help of family members. (4) Practice walking up and down steps with full weight bearing. Patients can use their own height of 375px wooden box (to be strong enough) to practice up and down steps; you can also climb stairs to practice up and down steps. (5) Knee straightening exercises: patients during hospitalization every day for a long time under the heel of the towel roll to practice the action of knee extension, 3 weeks after the start of the operation, should be under the heel of the towel roll can be achieved in a very short period of time after the complete straightening of the knee joint. If this level is not achieved 3 weeks after surgery, the exercises should be intensified. There are two ways to do this: one is to put a certain amount of weight on the top of the knee while putting a towel roll under the heel, and the amount of weight should be such that the knee is fully straightened 10 minutes after the weight is put on it. Secondly, the patient lies face down, puts the knee on the side of the bed, hangs a weight on the foot, and practices straightening. If the weight is too light, the knee extension will not reach the requirement after 10 minutes of practice, and if the weight is too heavy, the patient will not be able to hold on to it after less than 3-5 minutes of practice, so it is necessary to feel out the size of the weight, and it is good that the knee joint can be fully straightened after 10 minutes of practice. Exercise frequency: once a day is enough. After practicing knee extension, don’t practice knee flexion, because it is more difficult to flex the knee at this time. For example, if you practice knee extension in the morning, you should practice knee flexion in the afternoon. After practicing knee extension, do not force yourself to bend the knee to a natural angle within a short period of time, but let the knee naturally return to a relaxed state after practicing straightening. (6) Exercise of knee flexion: 2 weeks after surgery, the knee flexion can reach 110°. At 3 weeks after surgery, the knee flexion angle is not required to progress too fast, but to reach 115° on the basis of 2 weeks after surgery. The intensity of the exercises is once a day, and the total duration of an exercise is 30 minutes. After practicing knee flexion, do not force the knee to straighten, but let it straighten naturally. There should be a half-day gap between the knee flexion and knee extension exercises. Do not practice knee extension right after knee flexion. Flexion is much more painful than extension, and for every 1° of forward progression in the angle of flexion, the patient will feel severe pain. Therefore, the patient should be prepared for pain. If there is a significant increase in joint swelling after the exercise and a significant increase in joint pain, it means that the joint is reacting too much to the exercise. After too great a reaction occurs, the number of exercises can be changed to once every 2 days, and then to once a day when the strong reaction is over. (7) Quadriceps exercises: There are three main exercises: ① Straight leg raising exercises: Raise the affected limb at a 15° angle to the bed with it fully extended. Maintain this position until you are unable to do so. Put the leg on the bed to rest for a moment, continue to carry out the second straight leg raising exercise. ② half squatting exercise: this is the patient just after surgery to start half squatting exercise. Static squatting exercise method: posture with the Chinese martial arts horseback squatting crotch action or staking action. The patient’s legs apart, the distance between the two feet is slightly wider than the shoulder, the body to maintain an upright position, can not lean forward, at this time the knees began to bend squatting. The bending angle of the knees varies according to the patient’s physical condition and muscle strength. If the patient’s physical condition is good, the thigh muscle strength is good, the squatting angle can reach 90 ° knee flexion, if the patient’s physical condition is poor and the thigh muscle strength is weak, the knees can be mildly flexed, then the semi-squatting position is higher, the patient is more labor-saving, and with the increase in muscle strength after the practice and then increase the angle of knee flexion. According to their own physical condition to determine the number of exercises. The patients who just started to practice can practice with their backs against the wall in order to prevent falling. 7, 4 weeks after surgery: (1) Strengthen the quadriceps exercises. The exercises are the same as the straight leg raising exercises and half squatting exercises mentioned above. But the intensity and frequency should be increased. (2) Continue the exercises to mobilize the patella. (3) The knee flexion angle should reach 120° by the fourth week after surgery. The number of exercises is still 30 minutes once a day. Practice knee flexion and knee extension half a day apart. (4) The intensity of the knee extension exercises depends on the performance of the exercises during the first 3 weeks after surgery. If the knee extension has been practiced well in the first 3 weeks, then a little consolidation exercise can be done every day. If the knee extension is still stiff, practice the same knee extension as in the first 3 weeks after surgery. (5) Increase the frequency and time of stair climbing to improve the flexibility of the knee joint. 8. 5 weeks after surgery: (1) Continue the quadriceps exercises, the same method as before. (2) The knee flexion angle should be greater than 120°, but how much greater than 120° can be mastered by different patients. For example, for patients who are kneeling for religious activities, a knee flexion angle of 130° or more may be appropriate. For some patients, a knee flexion of 120° is sufficient for all activities in daily life. (3) The intensity of practicing knee extension depends on the performance of the exercises in the first 4 weeks after surgery. If the knee extension has been well practiced in the first 4 weeks, then a little consolidation exercise can be done every day. If the knee extension is still stiff, practice the same knee extension as in the first 4 weeks after surgery. (4) Since the angle of knee flexion and knee extension is now better, the patient can start practicing bicycle pedaling. There are two methods: one is to pedal a stationary bicycle, but pedal a stationary bicycle often need to go to the rehabilitation center to achieve; second, for patients who do not have the time or convenience to go to the hospital’s rehabilitation center or gym can be practiced at home to pedal a three-wheeled bicycle exercises. Because the three-wheeled bicycle is more stable, it is more suitable for patients to use. Moreover, three-wheeled bicycles can be ridden, which is more fun than pedaling a stationary bicycle. If the patient does not have a bicycle at home, he or she can borrow one from a neighbor, and the source can be easily solved. (5) Start practicing the balance function and proprioception of the knee joint. The method is to find a board as wide as the length of the feet, the length of the board should be able to allow the patient to stand on it with the feet a little apart. In the middle of the board below the nail on a cylindrical stick with a diameter of 125px, when practicing, the patient stood on the board, with the middle of the diameter of 125px stick as a fulcrum for the feet to rotate tilting action. Because it is just starting to practice twice a day, each practice can be 5 minutes. When practicing, a doctor or family member is required to protect you. 9, 6-8 weeks after surgery: (1) The focus is to consolidate the results of the knee flexion and knee extension angle exercises. (2) Increase the number of times and duration of going up and down stairs, riding a stationary bicycle or tricycle. (3) Increase the practice of knee balance function and proprioception. Patients can complete this exercise independently in the 6th-8th postoperative weeks, and the practice method is the same as that in the 5th postoperative week. (4) Increase the walking distance independently and freely. Walk slowly and in small steps, but try to achieve a completely normal posture with each step. Don’t limp or walk with a skip and a jump in order to accommodate the operated knee. Only by walking with a normal gait from the very beginning of your walking practice will you be able to walk normally as quickly as possible, and once you develop bad habits, it will be very difficult to correct them. Walking time and distance are determined by the knee’s response to walking. If the patient’s knee is obviously swollen and painful after walking a certain distance, the walking distance should be reduced. If the knee reacts to walking, but recovers overnight, the amount of walking is normal. 10, 9-12 weeks after surgery: (1) Resume daily life activities. (2) At this time, some patients still feel some tightness in the knee joint, which is mainly due to the formation of postoperative scar, so at this time we must strengthen the quadriceps muscle, N cord muscle (rear thigh muscle) and calf triceps muscle pulling exercises and massage to loosen the scar at the surgical incision, also can do quadriceps muscle pulling and stretching exercises. (3) Some patients may have soreness in the affected knee joint after a large dose of functional exercises, which is a normal response to postoperative rehabilitation, and can be given fusolin to inhibit soft tissue edema and pain. (4) During this period, patients often feel slight discomfort in the operated knee joint in one way or another, and the skin area around the surgical wound may have “numbness” or intermittent or pulsatile “electric-like” pain in the lateral side of the incision, which is mainly due to the fact that the nerves of the incision innervating the corresponding skin area are not fully functional, and the pain is mainly due to the fact that the incision has been made in the knee joint. These are mainly due to the regeneration of the nerves innervating the corresponding skin area in the incision, and the above symptoms can disappear on their own after half a year. (5) In the three months after the operation, the affected knee joints often have low-grade fever, and the joints can often have fluid accumulation, which is mainly due to the body’s reaction to the placement of the prosthesis or due to the stimulation of the knee joints during the knee joints’ activities in the functional training, and the above symptoms can disappear gradually and return to normal in the six months after the operation. If the affected knee joint is hot and swollen, you must contact the surgeon. 11, 3 months after surgery: Gradually resume physical activities, the patient can arrange dancing, swimming, golf, walking without distance limitation and non-strenuous tennis according to their own situation, but should avoid strenuous exercise. To recover satisfactorily after surgery, i.e., to return to the replaced knee joint without the slightest feeling of alienation, it often takes 9-12 months of adaptation.