Total knee arthroplasty (TKA) is a highly effective procedure with a postoperative rate of >90%. However, if the success of the procedure is based on the surgical technique without postoperative rehabilitation, the procedure will not be as effective as it should be [1]. Through clinical practice, we have developed a postoperative rehabilitation program for total knee arthroplasty. The aim is to restore the patient’s limb function and self-care ability through early rehabilitation training.
The main methods are preoperative guidance and postoperative training.
1. Pre-operative guidance
First of all, we should strengthen the static contraction of the quadriceps muscle of the affected limb and the active movement of the ankle joint, requiring the quadriceps muscle to be contracted for 10 seconds each time, and every 10 times is one group, and 5-10 groups are completed every day.
The patient should sit on the bed and perform straight leg raising and ankle flexion resistance exercises, the number of times can be determined according to the patient’s condition and repeated 2 to 3 times a day.
In addition, patients should be taught how to use crutches to prepare for walking with a cane after surgery.
2.Postoperative rehabilitation training
2.1 The first week after surgery
The purpose of this period is to reduce the patient’s symptoms, promote wound healing, prevent muscle atrophy, improve joint range of motion, and increase muscle strength.
2.1.1 On the day of surgery, maintain the functional position of the joint and keep the foot high and hip low position.
2.1.2 On the second to seventh postoperative days, the affected limb did static contraction of the quadriceps muscle, holding it for 10 seconds each time, with 10 sets of 10 times each day.
2.1.3 The patient sits on the bed and does straight leg raising exercise for the affected limb, without requiring the lifting height, but with a lag time of about 10 seconds.
2.1.4 Perform a dorsiflexion movement of the affected ankle joint, keeping that joint at 90°, and do a wrap-around movement of that joint repeated 15 times, completing 2 to 3 times a day.
2.1.5 Apply continuous passivemotion (CPM) machine to the affected limb in a painless state, with a starting angle of 0° and an ending angle of 20°, completing a round trip within 2 min, 4 hours per day [2], and try to reach or approach 90° within 1 week.
2.1.6 Modulated medium-frequency current is applied to the affected limb twice a day with a current density not exceeding 0.3 mA/cm2 to improve local blood circulation and promote wound healing.
2.2 The second week after surgery
Focus on strengthening the active movement of the affected limb in the non-weight-bearing state and improving the active range of motion of the joint.
2.2.1 The patient’s knee should be released from the beginning of the joint movement in a painless manner, with a small rhythmic back and forth movement of the joint.
2.2.2 The patient sits on the bed and completes 2.2.1 autonomously with the hip as the fixed point and the slide board placed under the affected foot and using it as the moving point.
2.2.3 Further strengthen the straight leg raising movement of the affected limb by fixing a pulley above the bed, holding the affected ankle joint with a sling at one end and controlled by the patient at the other end, and completing the straight leg raising movement through assisted movement, requiring the patient to raise the affected limb as high as possible and maintain the height, and gradually reduce the assistance of the hand and transition to active completion of this movement.
2.2.4 Encourage the patient to get out of bed. In the second half of the week, the center of gravity gradually shifts to the affected side and the patient stands upright in the parallel bar.
2.2.5 The angle of the CPM machine was increased to 90°-100°.
2.3 Postoperative week 3
Continue the active straight leg raising exercise to consolidate the previous training effect, restore the weight-bearing ability of the affected limb, strengthen the walking gait training, train the patient’s balance ability and further improve the joint range of motion.
2.3.1 To understand the patient’s balance ability, the patient can be asked to stand and the therapist push the patient back and forth, noting whether the patient can maintain his or her own balance.
2.3.2 Patients should practice walking with crutches, and when they are psychologically and physically able to do so, they should walk in parallel bars without crutches.
2.3.3 The patient is placed in the lateral position with the affected limb on top, straighten the knee joint to do abduction movement, the ankle joint is at 90°, on this basis, do back and forth swing exercise, the therapist exerts resistance in the opposite direction, the patient needs to overcome the resistance.
2.3.5 In the prone position, actively flex the affected knee, also with the help of the therapist.
2.3.6 Flexion of the knee joint under the action of the quadriceps trainer, starting from 90° with a weight of 1 kg, twice a day for 15 min each time.
2.3.7 Walking training on a treadmill with the patient looking forward with head up and chest out and no hip cocking.
2.3.8 Pedaling on a stationary bicycle with the cushion starting from the highest.
2.3.9 Patients should try to perform daily activities of living such as putting on pants and socks independently during this week.
2.4 Postoperative week 4 to 3 months
Focus on further enhancing the results of the 3rd week, increasing the range of motion and weight-bearing capacity of the affected limb, as well as the ability to take care of oneself.
2.4.1 Walk independently on a mildly inclined slope.
2.4.2 Independently put on shoes, socks, pants and other daily activities.
2.4.3 In addition to functional training for bending the knee, attention should be paid to functional training for knee extension, such as leg press in sitting position.
2.4.4 In the early stage, the patient should mainly rely on crutches to go up and down stairs, with the healthy leg supporting and the affected leg bearing weight below to partially bearing weight, requiring the healthy leg to go up first and the affected leg to go down first.
3.Cautions
①When using low-frequency modulated medium-frequency current to act on the affected limb, the treatment current should not be the tolerated amount, and the standard of 0.3mA/cm2 should be strictly followed to avoid tissue damage.
②Prevent infection after surgery and apply antibiotics systemically or locally.
③Inquire about the patient’s condition and local discomfort before daily training to understand the amount of exercise, and pay attention to the results of the floating patellar test, if the floating patellar test is positive, then draw fluid to reduce pressure.
④The amount of training should be small to large and progressive, so as not to cause discomfort in the affected knee.
This is the training procedure we have developed for the postoperative period after total knee arthroplasty. After the patient goes home, he/she should also follow the above-mentioned training procedures and contact the rehabilitation surgeon and the surgeon for regular checkups to assess the function of the affected knee.