Efficacy of combining intravenous and topical dexamethasone against postoperative pain and function recovery after total knee arthroplasty: A prospective, double-blind, randomized controlled trial

Background Dexamethasone is a corticosteroid with powerful anti-inflammatory effects. This study aimed to explore whether combining intravenous and topical dexamethasone could improve postoperative pain, swelling, and function recovery after total knee arthroplasty (TKA). Methods In this prospective, double-blind, randomized controlled study, 90 patients undergoing primary unilateral TKA were randomized into a dexamethasone group, which received dexamethasone (10 mg) by periarticular infiltration during surgery, as well as intravenous dexamethasone (10 mg) before tourniquet release and at 12 h postoperatively; or a control group, which received equal volumes of isotonic saline instead of dexamethasone. The primary outcome was postoperative pain, as assessed on the visual analogue scale (VAS). Secondary outcomes were postoperative consumption of morphine hydrochloride for rescue analgesia, postoperative swelling ratio of the thigh, knee, and tibia; functional recovery in terms of total range of motion (ROM) of knee and daily ambulation distance; postoperative inflammation biomarkers levels of C-reactive protein and interleukin-6; and postoperative complications. Results Resting VAS scores at postoperative 6, 12, and 24 h, and VAS scores during motion at postoperative 2, 6, 12, and 24 h were significantly lower in the dexamethasone group. The dexamethasone group also showed significantly less morphine consumption during the first 24 h after surgery and cumulatively during hospitalization, milder limb swelling at 24 and 48 h postoperatively, greater flexion and total ROM on postoperative day 1, and longer ambulation distance on postoperative days 1 and 2, and lower levels of inflammatory biomarkers on postoperative days 1 and 2. The dexamethasone group had significantly lower incidence of postoperative nausea and vomiting. Conclusion Compared with placebo, the combination of intravenous and topical dexamethasone can reduce pain, swelling, and inflammation after TKA, it also can improve functional recovery and reduce the incidence of postoperative nausea and vomiting.