Inclusion Criteria:  1. Patients between the ages of 40-75, who meet the indications for total knee arthroplasty(TKA) surgery, plan to undergo unilateral TKA surgery, can tolerate surgical trauma, and have no surgical contraindications; 2. Patients who have good medical obedience and can cooperate to complete the evaluation of various indicators after the operation and continue to receive follow-up; 3. There is no contraindications to combined spinal-epidural anesthesia; 4. Agree to accept this trial and sign an informed consent form.  Exclusion Criteria:  1. Allergic to test drugs; 2. Abnormal liver, kidney or heart function; 3. People who have chronic pain symptoms in other parts of the body other than the knee joint; 4. Patients with a history of multiple operations on the knee joint, or patients with abnormal anatomical structures; 5. Patients who cannot perform early functional exercise after unconventional knee replacement or other systemic diseases; 6. Cannot communicate with researchers normally.