Beyond Hemostasis: Exploring Intra-articular Tranexamic Acid's Analgesic Effect in Post-operative Care in Total Knee Arthroplasty - Original Article.

Introduction: Tranexamic acid (TXA) is widely recognized for its hemostatic properties, particularly in reducing blood loss during surgical procedures. Recent studies, however, suggest that TXA may have potential analgesic benefits beyond its role in hemostasis. This study aims to evaluate the efficacy of intra-articular TXA in reducing post-operative pain and improving early recovery outcomes in patients undergoing total knee arthroplasty (TKA).

Materials and methods: Fifty-four patients undergoing simultaneous bilateral TKA were randomly assigned to receive intra-articular TXA in one knee, with the contralateral knee serving as the control. A 1 g dose of TXA, diluted in 10 mL of normal saline, was administered intra-articularly after capsule and skin closure. In addition, 3 g of TXA were administered intravenously (1 g at 30 min preoperatively and 1 g each at 3 and 6 h postoperatively). Closed suction drains were placed for 24 h postoperatively to assess the drainage output. Pain levels were measured using the Visual Analog Scale (VAS) at 48 h, 3 weeks, 6 weeks, and 12 weeks, with the primary outcome being early pain relief and knee range of motion (ROM). Functional outcomes were assessed preoperatively and at 12 weeks follow-up, using the oxford knee score (OKS) and the knee injury and osteoarthritis outcome score for joint replacement (KOOS-JR).

Results: At 48 h postoperatively, the intra-articular TXA group exhibited statistically significant improvements in early pain relief, as measured by VAS scores (P = 0.004), and reduced 24-h closed drain output (P = 0.015) compared to the control group. A greater percentage of patients in the TXA group demonstrated superior knee ROM at 48 h (68.5% vs. 59.3% in the control group). Functional scores, as measured by the OKS and KOOS-JR, improved in both groups, with no significant differences between the study and control knees at the 12-week follow-up.

Conclusion: Intra-articular TXA significantly improves early post-operative pain control and reduces blood loss in TKA patients. These findings suggest that intra-articular TXA can be a valuable adjunct in multimodal analgesia, potentially reducing opioid consumption and enhancing recovery. Further studies are warranted to confirm these results and explore the long-term benefits of TXA in TKA.