BackgroundIntravenous tranexamic acid (IV TXA) is one of the most effective agents in use for reducing blood loss following total knee arthroplasty (TKA) but its safety regarding venous thromboembolic events (VTEs) remains in question. The direct, local application of TXA may reduce systemic toxicity whilst maintaining good or better bleeding control compared to IV TXA. The topical application of TXA via Hemovac drains has been reported previously with good results. However, there are no data on peri-articular TXA injections during TKA.MethodsWe conducted an open randomized, pilot study of peri-articular vs. IV TXA in 60 patients undergoing TKA. 30 patients received either: (i) 750 mg peri-articular TXA into the medial, lateral capsules and the quadriceps tendon prior to capsular closure and tourniquet deflation (group1), or (ii) 750 mg of IV TXA just before tourniquet deflation. Blood loss in the hemovac drain and hemoglobin (Hb) concentrations were measured at 24 and 48 h (h), and the number of blood transfusions and leg circumference measurements were recorded.ResultsAt 48 h, the total blood loss in the hemovac drain was 445 mL in group 1 vs. 520 mL in group 2 (p = 0.081) and the corresponding declines in Hb were 1.85 g/dL vs. 1.87 g/dL (p = 0.84). 16 patients received blood transfusions: 9 vs. 7 in groups 1 and 2, respectively (p = 0.928). There were no differences in thigh and lower leg circumferences, pain scores, knee flexion at discharge date and lengths of hospital stay. There were no clinically detected venous thromboembolic events.ConclusionThis pilot study has shown promising results for peri-articular TXA during TKA. Additional, larger studies are needed to confirm our results and be powered to show differences in efficacy and safety of peri-articular vs. IV TXA.Trial registrationClinicalTrials.gov Identifier NCT02829346. Retrospectively registered: 07/11/2016.