Post-operative rehabilitation is mainly focused on muscle strength training, mobility training, postural transfer training, and gait training. For each patient, a rehabilitation training program should be developed for each individual, and the training program should be finely adjusted according to the patient’s daily recovery status. Avoid emphasizing a certain training goal and increasing the intensity of training beyond the patient’s tolerable level, causing the patient to fear training and avoid training. Therefore, the training progress should be gradual, while timely communication with the patient should be made so that the patient understands that pain is inevitable during training and works with the physician to provide analgesic treatment to reduce the patient’s discomfort and pain during training.
For patients with bilateral total knee replacements, postoperative pain and muscle strength recovery will be slower than for unilateral replacements, therefore, more analgesic treatment and ROM training are needed to instruct patients to learn to train actively as soon as possible to consolidate the training effect, and to restore more knee flexion angle to facilitate future sitting and standing transfer and life. Patients with simultaneous bilateral replacements should also be weight-bearing a little later.
For special patients, such as tumor patients, with special prosthesis design, any rehabilitation plan should be fully communicated with the surgeon, especially the flexion training and weight-bearing time.
Postoperative days 1-3: The patient comes out of the operating room with the knee joint usually pressure bandaged, with a drainage tube and fixed in a knee extension brace. The discomfort of the knee joint and lower limb muscles is most obvious and the patient is weak during these three days. The rehabilitation training mainly focuses on eliminating swelling of the affected limb, relieving discomfort of the affected limb, increasing the knee flexion angle to maintain full knee extension and restoring control of the knee muscle control, and preventing DVT of the lower limb.
Rehabilitation goals.
Control and eliminate swelling
Prevention of DVT
Pain relief
Gradual restoration of ROM of the affected knee (full extension and control of knee flexion within 60°)
Increase muscle control of both lower extremities and be able to contract the quadriceps well to complete SLR
Training method.
Postural elevation of the affected limb, Tri-sets, Ankle pump, 20 times per hour
Heel padding, active knee compression every hour to keep the knee fully straight for 5 minutes, sitting up and stretching the muscles and joint capsule behind the knee joint in a sitting position to improve knee extension
Wear a knee extension brace at night to maintain full knee extension and avoid postoperative flexion contracture
Release the knee extension brace on the first postoperative day with a small range of assisted knee flexion of 20°, increasing by 10-15° daily, and increasing to 60° on the third day
For SLR centrifugal muscle exercises, start with lateral SLR in the healthy position, followed by hip flexion with knee extension in the healthy position, and then try SLR in the supine position (with knee extension brace fixed) if you can do it easily
Encourage the patient to sit up in bed and avoid prolonged lying down
After drainage tube removal, add continuous pressure cold therapy for 30-45 minutes once in the morning and once in the afternoon
Exercises for the extensor muscles of the healthy leg and upper extremity to prepare for the floor walker training
It is appropriate to increase the angle of CPM use by 5-10° daily, and to run slowly during small-angle training, while encouraging patients to actively participate in following the CPM flexion and extension of the knee joint, and to strengthen the exercises for knee extension after CPM use
At this stage, if the patient achieves 60° of knee flexion, actively completes SLR training and the swelling subsides well, the next stage of training can be performed.
Postoperative 4-7 days: At this stage the patient’s swelling of the affected limb begins to gradually subside, control of the muscles of the lower limb is much improved, and the angle of knee flexion is increased to 90°. For patients with high-flexion vacations, the angle of knee flexion should be increased as much as possible without causing significant pain and swelling. In patients with poor active participation or particularly stiff and swollen joints, the use of CPM is mandatory, but at the same time full knee extension must be consolidated. Patients are encouraged to get out of bed and use a walker or crutches for tolerable weight-bearing standing and training for weight transfer.
Rehabilitation goals.
Eliminate the swelling and pain bothering the patient
Increase active knee flexion to 90° or greater and maintain and consolidate full knee extension
Strengthen the quadriceps muscles with SLR, TKE, etc.
Increase knee flexibility and coordination
TTWB-WBAT
Balance and gait training
Training methods.
Increase knee flexion to 90° using CPM or Wall slide, and for patients with high flexion vacations, increase the angle of knee flexion as much as possible (to control swelling)
Active knee flexion and extension training (sliding knee flexion and extension on supine bed or sliding knee flexion and extension back and forth with foot on the floor while sitting in a chair)
Consolidate knee extension for 5 minutes every hour (high pressure knee pad under foot, or sitting knee extension and stretching)
Relaxed back and forth leg swing at the bedside to increase flexibility of the affected knee
SLR in all directions, if there is no lag in knee extension, SLR can be trained off the knee extension brace
TKE, bridging, N cord muscle strength training
NMES to promote quadriceps control
Supported standing with knee brace immobilization, balance and gait training on the second day
Left-right and right-posterior transfer of the center of gravity (25% weight bearing on the affected leg)
Knee flexion of the affected leg in the standing position
Stepping in place
Cold compresses for pain relief before training and swelling after training
Assisted body position transfer training
At this stage, if the patient reaches 0-90° of knee flexion and extension, no lag in knee extension, and can complete the weight transfer training well, the next stage of training will begin.
Post-operative 8-14 days: In the second week after surgery, the patient’s control of knee flexion and extension is improved. At this time, the main focus of training is on continuing to increase ROM and training of lower limb muscle strength and walking ability.
Rehabilitation goals.
Pain control
Consolidation of knee extension
Increased knee flexion to 100-110° and 110-120° in hyperflexion vacations
Good weight bearing and closed chain muscle strength control of the lower extremity
Restoration of normal gait, improved walking ability, independent walker or crutch supported walking
Self-supported up and down steps exercises
Training methods.
Active knee flexion in supine, standing and sitting positions
Consolidation of full knee extension
Power bike low load exercises, gradually lowering the seat height
SLR, supine and TKE under weight
Standing knee flexion and heel lift exercises
15° squat in supported standing (increase weight bearing on the affected leg to 50%)
Lower extremity centrifugal weight training
Independent postural transfer training, emphasizing control and transfer of the center of gravity
Partial weight-bearing walking training, backward and lateral walking training
Adjusting one’s center of gravity and walking direction over obstacles and in the face of sudden external factors
Self-supporting step-up and step-down exercises
Post-training cold compresses
It is important to restore the strength of the quadriceps, especially the medial femoral oblique muscle, and the N cord muscle, which play an important role in the dynamic stability of the knee joint and the control and balance of the knee joint during weight-bearing, so it is crucial to train the muscles around the knee joint after surgery.
Some patients may experience joint stiffness after knee arthroplasty, and ROM training is arduous and ineffective. In such patients, the adverse effects of knee swelling should be controlled and improved, and a more acceptable method of ROM training should be found. Keep the surgeon informed of the patient’s training progress, especially if there is no significant progress or regression by the second postoperative week.
Patients should be discharged from the hospital 14 days after surgery. ROM, muscle strength, postural transfer and ADL should be evaluated before discharge, and a discharge training plan should be formulated based on the evaluation results, and patients should be instructed to continue training at home or referred to a rehabilitation center.
2 weeks to 1 month after surgery: In this stage, patients mainly exercise on their own to maintain and consolidate ROM, muscle strength and walking ability, and gradually return to normal life. For patients with slower recovery of muscle strength or more difficult recovery of ROM, they will return to the outpatient clinic 3 times a week to continue training under the guidance of the therapist. For older patients with more severe osteoporosis, full weight-bearing is preferable later.
Rehabilitation goals.
Consolidation of ROM and muscle strength training
Good lower limb coordination motor ability
Good ability to live on one’s own at home
Stable walking ability to prevent falls
Accompanied walking training in simple external environment
Increase aerobic exercise to increase physical fitness and endurance
Training methods
Self-improvement of muscle strength and ROM training every morning and afternoon
Gradually increase weight bearing to full weight bearing
Decrease weight reliance on the healthy leg
Restore good gait
Balance and anti-fall exercises
Return to normal daily life at home
Daily supported walking in the area with family members
Cold compresses after ROM and walking exercises
At this stage, if the patient obtains good ROM and weight-bearing muscle strength of the lower extremities and the ability to transfer to an active and independent position, he/she will move to the next stage of training.
One month to two months after surgery: In this stage, wound pain and joint swelling gradually return to normal, consolidate the previous ROM and muscle strength, and resume normal daily life.
Rehabilitation goals.
Stabilization of ROM, full range of motion without pain
Increase weight-bearing muscle strength in the lower extremities
Improve motor ability
Walking off the crutches
Training methods.
Continue all ROM and plyometric training from previous phase, once daily
One-legged micro-squats
One-legged balance board training
Walking off crutches
Obstacle walking training
20 minutes of walking in a small area
Walking in the pool or training with a bicycle
Two months to four months after surgery: At this stage, patients basically integrate into normal life and are encouraged to participate in small-load sports exercises such as swimming, hiking, table tennis, bowling, bicycling, etc. under the condition of physical operation, but for sports with high intensity, body collision, lower limbs need to be repeatedly flexed and rotated such as basketball, soccer, tennis badminton, etc. are still avoided to increase the protection of the prosthesis and prevent falls.