IO Vancomycin Administration in TKA

This is a prospective, single-center, open-label study evaluating systemic vancomycin levels following preoperative intraosseous administration in patients undergoing primary unilateral total knee arthroplasty. Eligible participants will receive preoperative intraosseous vancomycin (500 mg in 100 mL saline) as part of standard perioperative infection prophylaxis. The study is open-label due to the nature of the intervention. Blood samples will be collected at predefined time points intraoperatively to measure serum vancomycin concentrations. Patients will be randomized to either a tourniquet or no tourniquet for these blood draws.