IRCT20170826035905N3 IRCT 2018-11-21 Baqiyatallah University of Medical Sciences/Trauma Research Center Evaluation of the effect of oral Oxycodone and Saphenous nerve block in knee replacement surgery Comparison of the Effect of Oral Oxycodone and Saphenous Nerve Block in Controlling the Acute Post-operative Pain in Patients Undergoing Knee Replacement Surgery 2016-04-03 anticipated 80 Complete https://irct.ir/trial/26996 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Randomization description: Based on random numbers chart, Blinding description: The evaluator is blind about the study groups and the investigator is unaware of the consequences of the intervention. N/A Regional Anesthesia and Pain Management. Intervention 1: In the first group, oral oxycodone was administered at a dose of 5 mg two hours before surgery and every six hours after operation based on patient request and presence of pain. Intervention 2: In the second group the saphenous nerve block is performed in the adductor canal under ultrasound guide with 16 cc bupivacaine 0.5% and epinephrine with concentration of 1: 200,000 . Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is The publication permit must be issued by the University