ملخص الدراسة

120 patients undergoing primary total knee arthroplasty (TKA) were randomized to receive either 16 mg oral dexamethasone (DEX-16), 8 mg oral dexamethasone (DEX-8), or a placebo. The primary outcome of interest was pain intensity at rest and during motion measured using a 100-mm visual analogue scale (VAS). Secondary outcomes included opioid consumption, postoperative nausea and vomiting (PONV), fasting blood sugar (FBS), levels of C-reactive protein (CRP), knee range of motion (ROM), the Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, and Forgotten Joint Score (FJS). Outcomes were assessed every 6 hours for 48 hours postoperatively and up to 3 months. Overall, the results of the study revealed that both dexamethasone groups demonstrated reduced pain at rest compared with placebo, while the 16-mg dose provided significantly greater pain reduction during motion. These findings suggest a dose-response effect, with higher-dose oral dexamethasone providing superior early postoperative analgesia after TKA.