Intravenous vs Oral Acetaminophen as an Adjunct to Multimodal Analgesia After Total Knee Arthroplasty: A Prospective, Randomized, Double-Blind Clinical Trial

174 patients scheduled for primary unilateral total knee arthroplasty were randomized to postoperative intravenous acetaminophen, postoperative oral acetaminophen, or postoperative placebo, all of these treatments were given in addition to a multimodal analgesia regimen. Patients were assessed for analgesia outcomes, including pain scores and opioid consumption, within the postanaesthesia care unit and over the first 24 hours postoperatively. Results demonstrated no significant differences between the three groups for any outcome measured.