Continuous passive joint motion was trained for 30 min per day on each replacement knee, with the initial range of knee motion tolerated by the patient, and gradually increasing the range of knee flexion, stopping CPM training when the passive knee flexion range was ≥120 degrees. In the seated position, the patient gradually transitioned from a padded seat to a normal height seat to accommodate the range of flexion of the replacement knee; in the seated position, a small medicine bottle was controlled with the plantar aspect of the affected foot, and active knee flexion was induced by rolling the bottle back and forth. When the knee is flexed to the maximum tolerable range hold for 30 seconds, then continue rolling and repeat the training 3 to 5 times (at this time the proximal end of the knee is the fixed arm and the distal end is the movable arm); in the seated position keep both lower extremities shoulder width apart, move both feet backward to the maximum attainable range of knee flexion, fix both feet, move the patient’s hips forward in the seat to the tolerable position of the knee in flexion, then move backward, move back and forth 3 to 5 times to induce active flexion and extension of the knee movement (at this time the distal end of the knee is the fixed arm and the proximal end is the movable arm).