Intraosseous Tranexamic Acid for Reducing Blood Loss in Total Knee Arthroplasty

This prospective, single-center, randomized, double-blind, placebo-controlled trial aims to evaluate the efficacy and safety of local intraosseous tranexamic acid administration for reducing perioperative blood loss in patients undergoing primary unilateral total knee arthroplasty (TKA). A total of 70 patients with primary knee osteoarthritis will be randomly assigned in a 1:1 ratio to either the tranexamic acid group or the placebo control group. Before skin incision, participants in the experimental group will receive local intraosseous tranexamic acid, while participants in the control group will receive an equal volume of normal saline using the same injection procedure. The primary outcome is total perioperative blood loss. Secondary outcomes include postoperative hemoglobin reduction, transfusion requirements, pain, knee swelling, range of motion, functional recovery, length of hospital stay, and postoperative complications. Participants will be followed for up to 3 months after surgery.

Inclusion Criteria: * Age 50 to 85 years. * Diagnosis of primary knee osteoarthritis. * Scheduled to undergo primary unilateral total knee arthroplasty. * American Society of Anesthesiologists (ASA) physical status classification I to III. * Willing to participate in the study and able to provide written informed consent. Exclusion Criteria: * Known allergy or hypersensitivity to tranexamic acid. * History of thromboembolic disease, including deep vein thrombosis or pulmonary embolism. * Known hypercoagulable state or current use of anticoagulant therapy, except for protocol-permitted perioperative anticoagulation * Severe cardiac, hepatic, or renal dysfunction. * History of vascular stent implantation or peripheral vascular disease. * Active infection or previous surgery on the study knee. * Abnormal coagulation function, including an international normalized ratio (INR) greater than 1.5. * Pregnancy or breastfeeding.