Artificial total knee arthroplasty is a kind of surgery with very definite efficacy. If we only put the success of the surgery on the surgical technique but do not carry out effective rehabilitation training, we can not achieve the desired effect of the surgery. For knee replacement, functional exercises play an equally important role as surgery, which is related to the function and mobility of the knee joint in the future. Under the doctor’s guidance, the earlier the functional exercise starts, the better. Functional exercises should focus on active activities, supplemented by passive activities. It is as important, if not more important, to practice straightening and flexing the knee. It is normal to feel pain during early activities, and it is important not to be afraid of pain and lose the optimal period for practicing activities (within one week after surgery), thus affecting the function of the knee joint. The purpose of postoperative rehabilitation is to restore the function of the patient’s limbs and the ability of self-care through early functional training. Ankle pump action: foot and ankle extension and flexion activities can be started after waking up from anesthesia, 2 to 3 minutes each time, 2 to 3 times per hour. Li Xiaohui, Department of Joint Surgery, Tianjin Hospital Quadriceps Exercises: On the second day after surgery, start quadriceps exercises to maintain muscle tone. Try your best to dorsiflex the ankle joint, straighten the knee joint to do leg raising for 5 seconds, relax for 5 seconds and then repeat until the thigh muscles feel fatigue. Knee lifting exercises: straighten the lower limbs, as for quadriceps exercises, lift the leg away from the bed for more than ten centimeters, maintain 5 to 10 seconds, slowly put it down, repeat this action until the thighs feel fatigue. You can also do straight leg raising exercises in sitting position, by contracting the thigh muscles, make the knee straight and hold it for 5 to 10 seconds. Early activities on the ground On the second day after surgery, you can practice standing on the ground under the instruction of the doctor. On the third to fourth day after surgery, after the postoperative inflammatory reaction subsides, you can begin to do short-distance walking exercises. These early exercises help to regain muscle strength around the knee, improve joint mobility and restore balance and coordination. Walking Exercises Proper walking is the best way to help your knee recover, and you will need to start walking with a walker or crutches. First of all, you should feel comfortable and be able to maintain balance when standing upright, then move the walker or crutches forward for a small distance, straighten the knee on the operative side and move forward, first make the foot follow the ground, move the body forward, then flatten the foot, and finally the toes leave the ground. Walking frequency, pace distance and speed should be even. When the muscle strength and endurance have increased, you can gradually extend the walking time. Walking up and down stairs Walking up and down stairs requires strength and coordination, and is the best exercise to enhance body strength and endurance, which needs to be helped at the beginning until sufficient strength and balance coordination is regained. Post-operative rehabilitation after total knee replacement should be individualized due to the patient’s physique, condition, psychological quality, subjective requirements, and surgical procedure. In addition, since patients who receive total knee replacement have a history of long-term pain, deformity and dysfunction of the knee joint, functional exercises should be performed in a gradual and orderly manner, and should not be rushed in order to avoid undue injuries.