IRCT20141009019470N87 IRCT 2019-08-26 Shiraz University of Medical Sciences The Effect of Melatonin on Pneumatic Tourniquet Ischemia Reperfusion Injury in Lower Extremity Orthopedic Operation Study of the Effect of Melatonin on Pneumatic Tourniquet Ischemia Reperfusion Injury in Lower Extremity Orthopedic Operation 2019-09-11 anticipated 40 Complete https://irct.ir/trial/40796 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Randomization description: Patients will be assigned to each of the study groups based on the randomization table obtained from Randomization.com, Blinding description: Melatonin and placebo tablets are given by a person who is unaware of the study groups the night before surgery and before the patient enters the operating room. The person who is responsible for collecting the data in the operating room and recovery room was also blinded to the study. Laboratory experts and statisticians responsible for data analysis have also been blinded to the study. 2-3 Orthopedic surgery of the lower extrimites. Intervention 1: Intervention group: Intervention group: Patients in melatonin group receive 10 mg oral melatonin tablets the night before surgery and 2 hours before surgery. Intervention 2: Control group: Control group: Patients receive placebo orally the night before surgery and 2 hours before surgery. 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 It is against our policies.