The Effect of Dexamethasone Administration Route on Pain and Inflammatory Response in iPACK With ACB for Total Knee Arthroplasty - written in plain language according to ClinicalTrials.gov standards: The goal of this clinical trial is to learn how the route of dexamethasone administration (either through the vein or nerve block) affects pain and inflammation in people having total knee replacement surgery. All participants will receive two types of nerve blocks before surgery: an iPACK block and an adductor canal block (ACB), which help control pain after the operation. The main questions the study aims to answer are: Does injecting dexamethasone into the nerve block reduce pain more effectively than giving it by vein? Which method leads to a lower inflammatory response after surgery? Researchers will compare the two groups to see which route offers better pain relief and less swelling after knee surgery. Participants will: Be randomly assigned to receive dexamethasone either in the nerve block or by IV Receive standard care for total knee replacement Rate their pain and have blood tests after surgery to measure inflammation