Comparison of Outcomes of Multimodal Intraosseous Femoral Injection and Multimodal Intraosseous Tibial Injection: A Randomized Controlled Trial in Simultaneous Bilateral Total Knee Arthroplasty Patients

PURPOSE: Periarticular multimodal analgesia is a standard pain relief method for total knee arthroplasty (TKA) patients. Recent studies have demonstrated that intraosseous injections of pain relievers and antifibrinolytic agents provide statistically significant reductions in pain and blood loss. This study aimed to compare the outcomes of multimodal intraosseous femoral injections with those of tibial injections in patients undergoing bilateral TKA. METHODS: A double-blind, randomized controlled trial was done in 40 individuals. Patients received multimodal intraosseous injections at either the femur or tibia for each TKA, with the site alternating between groups. Postoperative outcomes assessed included Visual Analog Scale (VAS) pain score, postoperative blood loss, amount of painkiller used after surgery, range of motion, adverse effects, and complications. RESULTS: The primary outcomes were postoperative pain and blood loss. No significant differences were observed in VAS pain scores between groups at any time point; for example, at 12 hours, the mean difference was 0.06 (95% CI, −0.63 to 0.51, P = 0.149). However, the femoral site demonstrated significantly lower postoperative blood loss through drainage with a mean difference of −60.8 mL (95% CI, −98.54 to −23.06, P < 0.001) and lower total blood loss (mean difference −61.9 mL, 95% CI, −101.89 to −21.90, P < 0.001). CONCLUSION: Multimodal intraosseous injection at the femoral site seemed to be as effective for pain management as at the tibial site, but it resulted in markedly reduced postoperative blood loss in patients undergoing TKA. Additional research is required to explore long-term benefits of this technique and confirm its safety profile.