The purpose of this clinical study was to identify the risk factors for postoperative pain outburst in patients undergoing arthroscopic knee surgery after Oliceridine and nerve block, and to evaluate the effect of oxeridine on early rehabilitation exercise in patients. A total of 320 patients undergoing arthroscopic knee arthroscopy under general anesthesia combined with femoral nerve block were selected to record the time and duration of postoperative pain outbreak, pain degree, age, gender, operation type, previous surgical history and other related risk factors.

Inclusion Criteria:

1. Age 18-70 years old;2. Body mass index (BMI) 18-30kg /m2;3. American Society of Anesthesiologists (ASA) Grade I to II;4. Hospital stay >24h.

Exclusion Criteria:

1. Patients who cannot understand the numerical rating scale score and give feedback;2. Known allergy to the drug in the study;3. Infection of puncture site with nerve block;4. Oral analgesics for more than 2 weeks before surgery;5. Long-term use of glucocorticoids;6. Simultaneous surgery on both limbs;7. A psychopath;8. Severe compound trauma;9. Pregnant and lactating women.

General anesthesia combined with femoral nerve block was selected for knee arthroscopic day surgery