Effect of Adding Perineural Methylprednisolone to Peripheral Nerve Blocks Combined With Intravenous Dexamethasone for Prolonged Postdischarge Analgesia After Fast-track Total Knee Arthroplasty

Abstract

Patients undergoing total knee arthroplasty (TKA) may experience moderate-to-severe subacute pain after hospital discharge that may be undermanaged. We aimed to evaluate the effect of methylprednisolone added to ultrasound-guided peripheral nerve blocks (PNBs) combined with multimodal analgesia including intravenous dexamethasone for prolonged analgesia after early discharge. We randomized 80 patients who underwent fast-track TKA into 2 groups. All patients received a periarticular injection, PNBs, and multiple doses of intravenous dexamethasone. The methylprednisolone group received 140mg methylprednisolone in PNBs, while the nonmethylprednisolone group did not. The primary outcome was the incidence of moderate-to-severe pain (Numerical Rating Scale ≥4) during the first 12 postdischarge days. The secondary outcomes included pain scores until 3 postoperative months, incidence of rebound pain, functional performances, patient satisfaction, and adverse events. No significant between-group differences were noted in the incidence of moderate-to-severe pain during the first 12 postdischarge days (nonmethylprednisolone vs. methylprednisolone groups: 70% vs. 69.2%, P=0.941). However, this incidence was significantly higher in the methylprednisolone group between 2 weeks and 1 month (P=0.015) and between 1 and 3 months (P=0.004) postoperatively. No between-group differences in the Numerical Rating Scale scores at the postdischarge time points, incidence of rebound pain, and functional performance results were noted. Adding perineural methylprednisolone to ultrasound-guided PNBs for multimodal analgesia with intravenous dexamethasone did not prolong analgesia and improved the functional ability after fast-track TKA within 12 postdischarge days. However, the incidence moderate-to-severe pain may increase between the 2-week and 3-month follow-up.