Efficacy of preemptive multimodal analgesia initiated at various time points before total knee arthroplasty: a prospective, double-blind randomized controlled trial

Preemptive multimodal analgesia (PMA) is commonly employed for pain control after total knee arthroplasty (TKA). However, the optimal timing for initiating PMA remains unclear. This study aimed to compare the efficacy of PMA administered at different time points before TKA.

In this prospective, double-blind, placebo-controlled, randomized trial, 120 patients who underwent TKA were randomized into three groups. PMA (200 mg celecoxib and 150 mg pregabalin administered every 12 h) was initiated 48 h (group A), 24 h (group B), and 1 h (group C) before surgery. The primary outcome was the postoperative administration of morphine hydrochloride as a rescue analgesic. Secondary outcomes included time to first rescue analgesia, postoperative pain assessed using the visual analog scale (VAS), functional recovery assessed by knee motion range and ambulation distance, time until hospital discharge, and complication rates.

Compared with group C, groups A and B exhibited significantly lower morphine consumption within 24 h after surgery, lower total morphine consumption, longer time to first rescue analgesia, and superior range of knee motion on the day of surgery. Groups A and B did not exhibit significant differences in these outcomes. The three groups did not differ significantly in postoperative VAS pain scores, ambulation distance, length of hospital stay, or complication rates.

In comparison with PMA starting at 1 h preoperatively, initiating PMA at 24 and 48 h preoperatively provided better postoperative pain relief. Considering the aim of minimizing the amount of ineffective medication received by patients, initiating PMA at 24 h preoperatively may be a more favorable option for patients undergoing TKA. However, the clinical significance of our results and the optimal starting time for PMA require further investigation.